Most Recent Comments

Flat Earth Sophistry The science of induced travel is well proven, but Oregon DOTs is in utter denial Widening freeways not only fails to reduce congestion, it inevitably results in more vehicle travel and more pollution The Oregon Department of Transportation has published a technical manual banning the consideration of induced travel in Oregon highway projects. The Oregon Department of Transportation wants to pretend that induced travel doesn’t exist. Using federal funds, it has written a new handbook on how to plan for highways that makes some preposterous and undocumented claims about the induced travel. It explicitly prohibits planners and consultants from using peer-reviewed, scientifically based tools, like the Induced Travel Calculator, developed by the University of California Sustainable Transportation Center, and mandated by the California Department of Transportation for the analysis of the environmental effects of freeways. The tortured denial by the Oregon Department of Transportation engages in some blatant sophistry that tries to create a false distinction between “latent” demand and “induced demand.” If we just call it “latent demand” then somehow it doesn’t count. Turn to page 6-79 of ODOT’s newly published “Analysis Procedures Manual“. The APM is a technical guide to using traffic data to plan future roadways. Here you find a red-bordered text box with a bold graphic STOP sign, explicitly banning planners and analysts from using the induced travel calculator. “The use of these calculator types shall not be used to estimate induced and latent demand effects on ODOT-funded projects . . . ” This kind of foot-stomping, hand-waving denial is reminiscent of the Catholic church’s harrumphing denials of Copernicus and Galileo’s observations of the universe. But induced travel is extremely well-established science, and Oregon DOT shows itself to be modern day a flat-earth science denier. What the Scientific Literature Shows The economic and scientific literature on induced travel is unambiguous: Increasing road capacity, by whatever means, lowers the perceived cost of driving and results in more travel. The phenomenon is now so well-established that its called the “Fundamental Law of Road Congestion.” The economics are straightforward: expanding the supply of highways lowers the cost of driving, and faced with a lower cost of driving, people drive more. In this classic diagram, the supply curve shifts outward (to the right) lowering the cost of driving and increasing the number of miles driven. The best available science shows that this generated travel follows a unit elasticity: a one percent increase in roadway capacity creates a one percent increase in vehicle miles traveled. To claim otherwise is to simply be in denial about the fundamental economics of the price elasticity of demand: lowering the price of something (in this case the time cost of using a particular roadway) tends to increase the volume consumed. There have been numerous studies which have all reached similar conclusions about the empirical nature of this relationship. Two of the leading scholars on the subject, the University of California’s Susan Handy and James Volker present a meta-analysis of studies of induced travel. Their results are summarized on the following table. In studies in the US and in other developed countries, there’s a strong and consistent relationship between expanded roadways and additional travel. In the long run, estimates of the elasticity of induced travel are around 1.0, meaning that a one percent increase in road capacity tends to lead to a one percent increase in vehicle miles traveled. The authoritative Traffic Engineering Handbook summarizes the literature on induced demand as follows: . . . the long-run elasticities of VMT with respect to road space is generally 0.5 to 1.0 after controlling for population growth and income, with values of almost 1.0, suggesting that new road space is totally filled by generated traffic where congestion is relatively severe. Kara Kockelman (2011), “Traffic Congestion,” Chapter 22, Transportation Engineering Handbook, McGraw Hill . ODOT asserts that it can ignore all this literature. ODOT argues, in essence, that even thought the consensus is for a unit elasticity, that here in Oregon, contra all this published literature, it believes the real coefficient of these equations is zero: that a one percent increase in roadway capacity would lead to no increase whatsoever in travel demand. In essence, the ODOT Analysis Methods Manual tells planners to ignore induced demand entirely. Latent demand is induced demand. The apparent justification for this conclusion is that there’s something called “latent” demand that’s different from “induced” demand. Oregon DOT falsely claims that there is a difference between “latent” demand and “induced” demand. Here’s what they are saying… Latent Demand – this is demand for transportation that consumers do not utilize because they cannot afford the cost or it is not currently available. Latent demand responses are typically associated with network limitations, such as capacity constraints . . . Latent demand does not include induced demand. Induced demand – new demand for travel that did not exist prior to the build scenario. This is above and beyond forecasted and latent demand associated with planned land use, it is demand that is the result of changes in land use (zone changes) or economic conditions that create new trips. (ODOT Analysis Procedures Manual, June 2022, emphasis added). Denying that “latent” demand is induced demand is not supported in the literature. No other study uses these terms in this fashion, or makes this distinction between “induced” and “latent” demand. This is ODOT’s Through the Looking Glass moment: “When I use a word,” Humpty Dumpty said, in rather a scornful tone, “it means just what I choose it to mean- neither more nor less.” Ben and Jerry observe the latent demand for ice cream every year when they drop the price of a cone to zero, and people line up around the block. These are all people who would love to have ice cream, if only it were free. The lines around the block are “induced ice cream eating”, as the zero price of ice cream converts “latent demand” into “actual demand.” But we know empirically that travel changes rapidly in response to available highway capacity. That’s true both in the case of expansions and contractions in capacity. People rapidly and radically change their travel distances and trip making in response to changes in capacity. Predicted “carmaggedons” in the face of reductions of capacity from bridge closures, highway collapses, construction projects, demolitions of highways, and other similar events cause traffic disappearance. Ultimately, this is pure sophistry: Whether you call it “latent” demand or “induced” demand, the effects are exactly the same: Adding more capacity to existing roadways increases the volume of vehicle travel. Oregon’s Analysis Procedures Manual vs. California’s Transportation Analysis Framework While OregonDOT has just published its “Analysis Procedures Manual” banning the use of induced travel calculators, its California counterpart, Caltrans has published guidelines that require the use of such a calculator to highway projects in the Golden State. What leads one state DOT to require the calculator, while the other bans it. Who is right? Let’s consider the processes and documentation that went into the CalTrans and ODOT publications. CalTrans adopted its Framework after a years-long study and review effort. It brought in outside experts, it conducted and published a thorough literature review, and the Framework itself was the subject of public meetings. As the Framework document explains: Caltrans convened an expert panel of academics and practitioners through UC Berkeley Tech Transfer. The panel chair presented the group’s conclusions to stakeholders at a virtual Technical Roundtable prior to finalizing the group’s recommendations. Caltrans and State partners have accepted the panel’s recommendations, which are reflected in the guidance documents. In contrast, the Oregon Manual has no identified author, cites no academic literature, has not been subject to outside review by persons independent from the Oregon Department of Transportation. It is an unsubstantiated, unscientific polemic. It’s also possible (and indeed likely) that even without changes in land use, households and businesses will sort themselves differently among the existing stock of land and buildings. If travel is fast and free, people may choose to live at housing a great distance from their jobs (or conversely, commute to jobs at great distance from their homes). If travel is slower or more expensive, they may seek housing nearer their job, or look for jobs only closer to home in order to minimize the time and money costs of travel. The redistribution of population and employment among existing buildings in response to changes in travel costs is something that ODOT denies is even possible. What’s deeply ironic about the denial of induced demand is that highway departments have been counting on it to create an unending demand for their services for decades. Building more and wider roads has led to more driving and more car ownership, which has jammed existing roads to capacity, and led to calls for further widening. It’s a Sisyphean cycle that leads to ever more traffic and ever more spending on roads, which is just what highway departments and their vendors want. Induced Demand and Land Use Changes As Litman points out there are first-, second-, third- and fourth-order effects from highway capacity increases. Initially travel times get faster (first order). That prompts people to change whether, when, where and by what means they travel.( second order). The shift in travel patterns and accessibility may then prompt changes in land use (third order). Finally, the cumulative effect of a shift to sprawl and greater auto dependence may further amplify trip taking (fourth-order). Roadway expansion impacts tend to include: First order. Reduced congestion delay, increased traffic speeds. Second order. Changes in time, route, destination and mode. Third order. Land use changes. More dispersed, automobile-oriented development. Fourth order. Overall increase in automobile dependency. Degraded walking and cycling conditions (due to wider roads and increased traffic volumes), reduced public transit service (due to reduced demand and associated scale economies, sometimes called the Downs-Thomson paradox), and social stigma associated with alternative modes. The ODOT view is that the “second order” effects—changing times, routes, additional trip taking, and more miles traveled—somehow don’t count as “induced travel” if no changes in land use happen. Or, alternatively, if that travel is accurately predicted by a traffic model or anticipated in a plan (i.e. “above and beyond forecasted”) , that it also doesn’t count. The Land Use Red Herring But let’s have a look at the second part of the argument: That the transportation agency can ignore that part of induced demand that results from land use changes in response to the expansion of roadways, and that somehow, because Oregon has a system of land use planning that those effects simply don’t occur here. ODOT’s rhetorical position is that “Induced demand” can only occur in response to land use changes, and land use changes are impossible under Oregon’s land use system. The Oregon Department of Transportation likes to pretend that the only form of induced travel that is real is that which accompanies changes in land use. And they argue that because Oregon has strict land use laws, that investments in travel infrastructure can’t produce changes in land use. In general, Oregon faces low risk related to induced demand because of the state’s strong land use laws, which exist to prevent sprawl. Changes to land use must be approved by local jurisdictions, so a facility project cannot induce demand just by itself. ODOT’s reasoning is this: Induced demand only occurs when there is a land use change that necessitates a change in a land use plan. Because Oregon has land use plans, transportation projects somehow can’t create induced demand. This reasoning is wrong for two reasons: First, as we’ve already explained, “latent” demand–changes in transportation behavior in response to a capacity increase–can happen even without any change in land use, and this “latent” demand is, according to all the scientific literature “induced demand.” The second reason is that Oregon’s land use law doesn’t prevent or preclude changes in land use in response to changes in transportation infrastructure. What this misses is that the land use system is a permissive framework, and within that legal framework many possible patterns of population and employment are possible. For example, new housing can be built in infill locations (near transit, and proximate to more jobs) or it can be built at the urban periphery. Both outcomes are possible under the Oregon land use system. The key point about induced demand is that more investment in transportation infrastructure will make lower density, more far flung development even more attractive. And, importantly, a significant part of the demand for Oregon roadways comes from places not subject to the Oregon land use system (i.e. suburban Clark County Washington). Investing in more transportation capacity across the Columbia River will facilitate more low density sprawl in Washington, and added automobile trips on the I-5 and I-205 bridges as large fractions of these suburban and exurban households live and shop in Oregon. A lobbying campaign to deny induced demand There’s little question that ODOT officials are uncomfortable with the science of induced travel. And they’re eager to do anything they can to minimize or misrepresent or discredit the application of this scientific fact to transportation planning. For example, in 2021, ODOT sought funding through AASHTO (the lobbying organization of state highway agencies) to get a project funded to dispute induced demand. Bike Portland reported that its proposal made it clear that the agency was primarily interested in generating talking points to push back against application of induced demand to metro area freeway expansion projects. “While the road building era of the 1950s freeway networks is essentially complete, even minor strategies and investment intended to optimize existing roadway system assets are increasingly facing opposition in the name of “induced demand”…” Even as it is busily ignoring or denying the science of induced travel, the Oregon Department of Transportation regularly repeats the discredited myth that idling in traffic is a significant source of greenhouse gas emissions that can be reduced by widening roadways. Traffic Projections that Deny Induced Travel Lack Scientific Integrity To the extent that ODOT’s guidance limits what is included in a federally required environmental impact statement, it’s steadfast refusal to cite any sources for its claims, and its consistent ignorance of published scientific literature on induced travel constitutes a violation of the scientific integrity requirements of NEPA. § 1502.23 Methodology and scientific accuracy. Agencies shall ensure the professional integrity, including scientific integrity, of the discussions and analyses in environmental documents. Agencies shall make use of reliable existing data and resources. Agencies may make use of any reliable data sources, such as remotely gathered information or statistical models. They shall identify any methodologies used and shall make explicit reference to the scientific and other sources relied upon for conclusions in the statement. Agencies may place discussion of methodology in an appendix. Agencies are not required to undertake new scientific and technical research to inform their analyses. Nothing in this section is intended to prohibit agencies from compliance with the requirements of other statutes pertaining to scientific and technical research. Chuck Marohn, writing at Strong Towns explains that traffic engineers treat travel demand as a fixed and immutable quantity–they’ve build models and a world view that pretends that people will travel just as much whether they build a project or not. This view helps justify building ever more roads, but doesn’t reflect reality and ought to be treated as professional malpractice: The concept of “travel demand” is where traffic engineers have stunted their own intellectual development more than perhaps anywhere else. And they’ve done so for two reasons. First, it makes their models easier to run. It’s really difficult (impossible, really) to create models that factor in the behavioral responses of humans. Better to just assume a static level of demand, even though that assumption is a farce (remember, traffic models are all about justifying projects, not actually modeling what is going on in the world). Second, it allows traffic planners and engineers to position themselves and their craft as responding to demand, not creating it. That’s an important distinction because it allows them to be confident in what they do without having to struggle with the underlying reasons that things aren’t working. . . . Engineering in the auto age is about building—build, build, build—and not about optimizing or managing systems. When your ethos is merely to build more stuff, you develop myths and models that support that ethos. That’s what you’re seeing in the patently absurd assertion that additional capacity does not generate more trips. . . . In 2022, denying how highway expansions induce people to drive more should be considered professional malpractice. US Secretary of Transportation Pete Buttigieg clearly endorses the science of induced demand. In a recent television interview, Buttigieg told Chris Wallace: . . . here’s an entire science to this. And we have a lot of research partners. We have our own research institution called the Volpe Institute, which is in Cambridge, Massachusetts. . . . one of the challenges we have right now is you got more and more people in the country more and more people on the road. Just how to be smart about that. For example,it turns out that sometimes when you just want to get a lot of traffic on the roadway, and you just added lanes to it, all you get is more traffic, because it actually makes more people want to drive on that road and then you’re right back where you were. Discussion blog comments powered by Disqus Related Commentary Kate: Metro’s wildly inaccurate model overstates current traffic levels The case for the $7.5 billion Interstate Bridge Replacement Project is based on traffic projections from Metro's "Kate" tr... → Joe Cortright 14.10.2024 The Interstate Bridge Project’s Flawed Traffic Data The Interstate Bridge Replacement Project simply can't tell the truth about current traffic levels or recent growth rates.... → Joe Cortright 11.10.2024 The Week Observed, August 30, 2024 What City Observatory Did This Week There's no evidence of a housing bubble. Strong Towns Chuck Marohn has a recent blo... → Joe Cortright 30.8.2024 Another housing bubble brewing? Not really Another housing bubble? Strong Towns Chuck Marohn argues that we're in the midst of another housing bubble. He claims th... → Joe Cortright 29.8.2024 City Observatory’s Joe Cortright on the Housing Bubble–2005 In an op-ed published in the Portland, Oregonian on July 17, 2005, City Observatory director Joe Cortright predicted that ... → Joe Cortright 23.8.2024 The Week Observed, August 23, 2024 What City Observatory Did This Week How Metro's RTP illegally favors driving and violates state climate rules. Oregon'... → Joe Cortright 23.8.2024 How Metro’s RTP Illegally favors car travel and violates climate rules Oregon's planning rules require Portland area transportation plans to prioritize investments that reduce vehicle miles tra... → Joe Cortright 22.8.2024 The Week Observed, August 16, 2024 Must Read Portland advocates sue to block Rose Quarter Freeway widening. There's a new chapter in the long-running batt... → Joe Cortright 7.8.2024 What Matters to the Success of Cities City Observatory Portland, Oregon info@cityobservatory.org Supported by About Commentary Reports Subjects Subscribe Search Subscribe Stay up to date by entering your email We will never sell or share your email address. ✕ Search ✕ Main Subjects Reports Commentary Subscribe Search Flat Earth Sophistry By Joe Cortright 30.12.2022 The science of induced travel is well proven, but state DOTs are in utter denial Widening freeways not only fails to reduce congestion, it inevitably results in more vehicle travel and more pollution The Oregon Department of Transportation has published a technical manual banning the consideration of induced travel in Oregon highway projects. The Oregon Department of Transportation wants to pretend that induced travel doesn’t exist. Using federal funds, it has written a new handbook on how to plan for highways that makes some preposterous and undocumented claims about the induced travel. It explicitly prohibits planners and consultants from using peer-reviewed, scientifically based tools, like the Induced Travel Calculator, developed by the University of California Sustainable Transportation Center, and mandated by the California Department of Transportation for the analysis of the environmental effects of freeways. The tortured denial by the Oregon Department of Transportation engages in some blatant sophistry that tries to create a false distinction between “latent” demand and “induced demand.” If we just call it “latent demand” then somehow it doesn’t count. Turn to page 6-79 of ODOT’s newly published “Analysis Procedures Manual“. The APM is a technical guide to using traffic data to plan future roadways. Here you find a red-bordered text box with a bold graphic STOP sign, explicitly banning planners and analysts from using the induced travel calculator. “The use of these calculator types shall not be used to estimate induced and latent demand effects on ODOT-funded projects . . . ” This kind of foot-stomping, hand-waving denial is reminiscent of the Catholic church’s harrumphing denials of Copernicus and Galileo’s observations of the universe. But induced travel is extremely well-established science, and Oregon DOT shows itself to be modern day a flat-earth science denier. What the Scientific Literature Shows The economic and scientific literature on induced travel is unambiguous: Increasing road capacity, by whatever means, lowers the perceived cost of driving and results in more travel. The phenomenon is now so well-established that its called the “Fundamental Law of Road Congestion.” The economics are straightforward: expanding the supply of highways lowers the cost of driving, and faced with a lower cost of driving, people drive more. In this classic diagram, the supply curve shifts outward (to the right) lowering the cost of driving and increasing the number of miles driven. The best available science shows that this generated travel follows a unit elasticity: a one percent increase in roadway capacity creates a one percent increase in vehicle miles traveled. To claim otherwise is to simply be in denial about the fundamental economics of the price elasticity of demand: lowering the price of something (in this case the time cost of using a particular roadway) tends to increase the volume consumed. There have been numerous studies which have all reached similar conclusions about the empirical nature of this relationship. Two of the leading scholars on the subject, the University of California’s Susan Handy and James Volker present a meta-analysis of studies of induced travel. Their results are summarized on the following table. In studies in the US and in other developed countries, there’s a strong and consistent relationship between expanded roadways and additional travel. In the long run, estimates of the elasticity of induced travel are around 1.0, meaning that a one percent increase in road capacity tends to lead to a one percent increase in vehicle miles traveled. The authoritative Traffic Engineering Handbook summarizes the literature on induced demand as follows: . . . the long-run elasticities of VMT with respect to road space is generally 0.5 to 1.0 after controlling for population growth and income, with values of almost 1.0, suggesting that new road space is totally filled by generated traffic where congestion is relatively severe. Kara Kockelman (2011), “Traffic Congestion,” Chapter 22, Transportation Engineering Handbook, McGraw Hill . ODOT asserts that it can ignore all this literature. ODOT argues, in essence, that even thought the consensus is for a unit elasticity, that here in Oregon, contra all this published literature, it believes the real coefficient of these equations is zero: that a one percent increase in roadway capacity would lead to no increase whatsoever in travel demand. In essence, the ODOT Analysis Methods Manual tells planners to ignore induced demand entirely. Latent demand is induced demand. The apparent justification for this conclusion is that there’s something called “latent” demand that’s different from “induced” demand. Oregon DOT falsely claims that there is a difference between “latent” demand and “induced” demand. Here’s what they are saying… Latent Demand – this is demand for transportation that consumers do not utilize because they cannot afford the cost or it is not currently available. Latent demand responses are typically associated with network limitations, such as capacity constraints . . . Latent demand does not include induced demand. Induced demand – new demand for travel that did not exist prior to the build scenario. This is above and beyond forecasted and latent demand associated with planned land use, it is demand that is the result of changes in land use (zone changes) or economic conditions that create new trips. (ODOT Analysis Procedures Manual, June 2022, emphasis added). Denying that “latent” demand is induced demand is not supported in the literature. No other study uses these terms in this fashion, or makes this distinction between “induced” and “latent” demand. This is ODOT’s Through the Looking Glass moment: “When I use a word,” Humpty Dumpty said, in rather a scornful tone, “it means just what I choose it to mean- neither more nor less.” Ben and Jerry observe the latent demand for ice cream every year when they drop the price of a cone to zero, and people line up around the block. These are all people who would love to have ice cream, if only it were free. The lines around the block are “induced ice cream eating”, as the zero price of ice cream converts “latent demand” into “actual demand.” But we know empirically that travel changes rapidly in response to available highway capacity. That’s true both in the case of expansions and contractions in capacity. People rapidly and radically change their travel distances and trip making in response to changes in capacity. Predicted “carmaggedons” in the face of reductions of capacity from bridge closures, highway collapses, construction projects, demolitions of highways, and other similar events cause traffic disappearance. Ultimately, this is pure sophistry: Whether you call it “latent” demand or “induced” demand, the effects are exactly the same: Adding more capacity to existing roadways increases the volume of vehicle travel. Oregon’s Analysis Procedures Manual vs. California’s Transportation Analysis Framework While OregonDOT has just published its “Analysis Procedures Manual” banning the use of induced travel calculators, its California counterpart, Caltrans has published guidelines that require the use of such a calculator to highway projects in the Golden State. What leads one state DOT to require the calculator, while the other bans it. Who is right? Let’s consider the processes and documentation that went into the CalTrans and ODOT publications. CalTrans adopted its Framework after a years-long study and review effort. It brought in outside experts, it conducted and published a thorough literature review, and the Framework itself was the subject of public meetings. As the Framework document explains: Caltrans convened an expert panel of academics and practitioners through UC Berkeley Tech Transfer. The panel chair presented the group’s conclusions to stakeholders at a virtual Technical Roundtable prior to finalizing the group’s recommendations. Caltrans and State partners have accepted the panel’s recommendations, which are reflected in the guidance documents. In contrast, the Oregon Manual has no identified author, cites no academic literature, has not been subject to outside review by persons independent from the Oregon Department of Transportation. It is an unsubstantiated, unscientific polemic. It’s also possible (and indeed likely) that even without changes in land use, households and businesses will sort themselves differently among the existing stock of land and buildings. If travel is fast and free, people may choose to live at housing a great distance from their jobs (or conversely, commute to jobs at great distance from their homes). If travel is slower or more expensive, they may seek housing nearer their job, or look for jobs only closer to home in order to minimize the time and money costs of travel. The redistribution of population and employment among existing buildings in response to changes in travel costs is something that ODOT denies is even possible. What’s deeply ironic about the denial of induced demand is that highway departments have been counting on it to create an unending demand for their services for decades. Building more and wider roads has led to more driving and more car ownership, which has jammed existing roads to capacity, and led to calls for further widening. It’s a Sisyphean cycle that leads to ever more traffic and ever more spending on roads, which is just what highway departments and their vendors want. Induced Demand and Land Use Changes As Litman points out there are first-, second-, third- and fourth-order effects from highway capacity increases. Initially travel times get faster (first order). That prompts people to change whether, when, where and by what means they travel.( second order). The shift in travel patterns and accessibility may then prompt changes in land use (third order). Finally, the cumulative effect of a shift to sprawl and greater auto dependence may further amplify trip taking (fourth-order). Roadway expansion impacts tend to include: First order. Reduced congestion delay, increased traffic speeds. Second order. Changes in time, route, destination and mode. Third order. Land use changes. More dispersed, automobile-oriented development. Fourth order. Overall increase in automobile dependency. Degraded walking and cycling conditions (due to wider roads and increased traffic volumes), reduced public transit service (due to reduced demand and associated scale economies, sometimes called the Downs-Thomson paradox), and social stigma associated with alternative modes. The ODOT view is that the “second order” effects—changing times, routes, additional trip taking, and more miles traveled—somehow don’t count as “induced travel” if no changes in land use happen. Or, alternatively, if that travel is accurately predicted by a traffic model or anticipated in a plan (i.e. “above and beyond forecasted”) , that it also doesn’t count. The Land Use Red Herring But let’s have a look at the second part of the argument: That the transportation agency can ignore that part of induced demand that results from land use changes in response to the expansion of roadways, and that somehow, because Oregon has a system of land use planning that those effects simply don’t occur here. ODOT’s rhetorical position is that “Induced demand” can only occur in response to land use changes, and land use changes are impossible under Oregon’s land use system. The Oregon Department of Transportation likes to pretend that the only form of induced travel that is real is that which accompanies changes in land use. And they argue that because Oregon has strict land use laws, that investments in travel infrastructure can’t produce changes in land use. In general, Oregon faces low risk related to induced demand because of the state’s strong land use laws, which exist to prevent sprawl. Changes to land use must be approved by local jurisdictions, so a facility project cannot induce demand just by itself. ODOT’s reasoning is this: Induced demand only occurs when there is a land use change that necessitates a change in a land use plan. Because Oregon has land use plans, transportation projects somehow can’t create induced demand. This reasoning is wrong for two reasons: First, as we’ve already explained, “latent” demand–changes in transportation behavior in response to a capacity increase–can happen even without any change in land use, and this “latent” demand is, according to all the scientific literature “induced demand.” The second reason is that Oregon’s land use law doesn’t prevent or preclude changes in land use in response to changes in transportation infrastructure. What this misses is that the land use system is a permissive framework, and within that legal framework many possible patterns of population and employment are possible. For example, new housing can be built in infill locations (near transit, and proximate to more jobs) or it can be built at the urban periphery. Both outcomes are possible under the Oregon land use system. The key point about induced demand is that more investment in transportation infrastructure will make lower density, more far flung development even more attractive. And, importantly, a significant part of the demand for Oregon roadways comes from places not subject to the Oregon land use system (i.e. suburban Clark County Washington). Investing in more transportation capacity across the Columbia River will facilitate more low density sprawl in Washington, and added automobile trips on the I-5 and I-205 bridges as large fractions of these suburban and exurban households live and shop in Oregon. A lobbying campaign to deny induced demand There’s little question that ODOT officials are uncomfortable with the science of induced travel. And they’re eager to do anything they can to minimize or misrepresent or discredit the application of this scientific fact to transportation planning. For example, in 2021, ODOT sought funding through AASHTO (the lobbying organization of state highway agencies) to get a project funded to dispute induced demand. Bike Portland reported that its proposal made it clear that the agency was primarily interested in generating talking points to push back against application of induced demand to metro area freeway expansion projects. “While the road building era of the 1950s freeway networks is essentially complete, even minor strategies and investment intended to optimize existing roadway system assets are increasingly facing opposition in the name of “induced demand”…” Even as it is busily ignoring or denying the science of induced travel, the Oregon Department of Transportation regularly repeats the discredited myth that idling in traffic is a significant source of greenhouse gas emissions that can be reduced by widening roadways. Traffic Projections that Deny Induced Travel Lack Scientific Integrity To the extent that ODOT’s guidance limits what is included in a federally required environmental impact statement, it’s steadfast refusal to cite any sources for its claims, and its consistent ignorance of published scientific literature on induced travel constitutes a violation of the scientific integrity requirements of NEPA. § 1502.23 Methodology and scientific accuracy. Agencies shall ensure the professional integrity, including scientific integrity, of the discussions and analyses in environmental documents. Agencies shall make use of reliable existing data and resources. Agencies may make use of any reliable data sources, such as remotely gathered information or statistical models. They shall identify any methodologies used and shall make explicit reference to the scientific and other sources relied upon for conclusions in the statement. Agencies may place discussion of methodology in an appendix. Agencies are not required to undertake new scientific and technical research to inform their analyses. Nothing in this section is intended to prohibit agencies from compliance with the requirements of other statutes pertaining to scientific and technical research. Chuck Marohn, writing at Strong Towns explains that traffic engineers treat travel demand as a fixed and immutable quantity–they’ve build models and a world view that pretends that people will travel just as much whether they build a project or not. This view helps justify building ever more roads, but doesn’t reflect reality and ought to be treated as professional malpractice: The concept of “travel demand” is where traffic engineers have stunted their own intellectual development more than perhaps anywhere else. And they’ve done so for two reasons. First, it makes their models easier to run. It’s really difficult (impossible, really) to create models that factor in the behavioral responses of humans. Better to just assume a static level of demand, even though that assumption is a farce (remember, traffic models are all about justifying projects, not actually modeling what is going on in the world). Second, it allows traffic planners and engineers to position themselves and their craft as responding to demand, not creating it. That’s an important distinction because it allows them to be confident in what they do without having to struggle with the underlying reasons that things aren’t working. . . . Engineering in the auto age is about building—build, build, build—and not about optimizing or managing systems. When your ethos is merely to build more stuff, you develop myths and models that support that ethos. That’s what you’re seeing in the patently absurd assertion that additional capacity does not generate more trips. . . . In 2022, denying how highway expansions induce people to drive more should be considered professional malpractice. US Secretary of Transportation Pete Buttigieg clearly endorses the science of induced demand. In a recent television interview, Buttigieg told Chris Wallace: . . . here’s an entire science to this. And we have a lot of research partners. We have our own research institution called the Volpe Institute, which is in Cambridge, Massachusetts. . . . one of the challenges we have right now is you got more and more people in the country more and more people on the road. Just how to be smart about that. For example,it turns out that sometimes when you just want to get a lot of traffic on the roadway, and you just added lanes to it, all you get is more traffic, because it actually makes more people want to drive on that road and then you’re right back where you were. Discussion blog comments powered by Disqus Related Commentary Kate: Metro’s wildly inaccurate model overstates current traffic levels The case for the $7.5 billion Interstate Bridge Replacement Project is based on traffic projections from Metro's "Kate" tr... → Joe Cortright 14.10.2024 The Interstate Bridge Project’s Flawed Traffic Data The Interstate Bridge Replacement Project simply can't tell the truth about current traffic levels or recent growth rates.... → Joe Cortright 11.10.2024 The Week Observed, August 30, 2024 What City Observatory Did This Week There's no evidence of a housing bubble. Strong Towns Chuck Marohn has a recent blo... → Joe Cortright 30.8.2024 Another housing bubble brewing? Not really Another housing bubble? Strong Towns Chuck Marohn argues that we're in the midst of another housing bubble. He claims th... → Joe Cortright 29.8.2024 City Observatory’s Joe Cortright on the Housing Bubble–2005 In an op-ed published in the Portland, Oregonian on July 17, 2005, City Observatory director Joe Cortright predicted that ... → Joe Cortright 23.8.2024 The Week Observed, August 23, 2024 What City Observatory Did This Week How Metro's RTP illegally favors driving and violates state climate rules. Oregon'... → Joe Cortright 23.8.2024 How Metro’s RTP Illegally favors car travel and violates climate rules Oregon's planning rules require Portland area transportation plans to prioritize investments that reduce vehicle miles tra... → Joe Cortright 22.8.2024 The Week Observed, August 16, 2024 Must Read Portland advocates sue to block Rose Quarter Freeway widening. There's a new chapter in the long-running batt... → Joe Cortright 7.8.2024 What Matters to the Success of Cities City Observatory Portland, Oregon info@cityobservatory.org Supported by About Commentary Reports Subjects Subscribe Search Subscribe Stay up to date by entering your email We will never sell or share your email address. ✕ Search ✕ Main Subjects Reports Commentary Subscribe Search Flat Earth Sophistry By Joe Cortright 30.12.2022 The science of induced travel is well proven, but state DOTs are in utter denial Widening freeways not only fails to reduce congestion, it inevitably results in more vehicle travel and more pollution The Oregon Department of Transportation has published a technical manual banning the consideration of induced travel in Oregon highway projects. The Oregon Department of Transportation wants to pretend that induced travel doesn’t exist. Using federal funds, it has written a new handbook on how to plan for highways that makes some preposterous and undocumented claims about the induced travel. It explicitly prohibits planners and consultants from using peer-reviewed, scientifically based tools, like the Induced Travel Calculator, developed by the University of California Sustainable Transportation Center, and mandated by the California Department of Transportation for the analysis of the environmental effects of freeways. The tortured denial by the Oregon Department of Transportation engages in some blatant sophistry that tries to create a false distinction between “latent” demand and “induced demand.” If we just call it “latent demand” then somehow it doesn’t count. Turn to page 6-79 of ODOT’s newly published “Analysis Procedures Manual“. The APM is a technical guide to using traffic data to plan future roadways. Here you find a red-bordered text box with a bold graphic STOP sign, explicitly banning planners and analysts from using the induced travel calculator. “The use of these calculator types shall not be used to estimate induced and latent demand effects on ODOT-funded projects . . . ” This kind of foot-stomping, hand-waving denial is reminiscent of the Catholic church’s harrumphing denials of Copernicus and Galileo’s observations of the universe. But induced travel is extremely well-established science, and Oregon DOT shows itself to be modern day a flat-earth science denier. What the Scientific Literature Shows The economic and scientific literature on induced travel is unambiguous: Increasing road capacity, by whatever means, lowers the perceived cost of driving and results in more travel. The phenomenon is now so well-established that its called the “Fundamental Law of Road Congestion.” The economics are straightforward: expanding the supply of highways lowers the cost of driving, and faced with a lower cost of driving, people drive more. In this classic diagram, the supply curve shifts outward (to the right) lowering the cost of driving and increasing the number of miles driven. The best available science shows that this generated travel follows a unit elasticity: a one percent increase in roadway capacity creates a one percent increase in vehicle miles traveled. To claim otherwise is to simply be in denial about the fundamental economics of the price elasticity of demand: lowering the price of something (in this case the time cost of using a particular roadway) tends to increase the volume consumed. There have been numerous studies which have all reached similar conclusions about the empirical nature of this relationship. Two of the leading scholars on the subject, the University of California’s Susan Handy and James Volker present a meta-analysis of studies of induced travel. Their results are summarized on the following table. In studies in the US and in other developed countries, there’s a strong and consistent relationship between expanded roadways and additional travel. In the long run, estimates of the elasticity of induced travel are around 1.0, meaning that a one percent increase in road capacity tends to lead to a one percent increase in vehicle miles traveled. The authoritative Traffic Engineering Handbook summarizes the literature on induced demand as follows: . . . the long-run elasticities of VMT with respect to road space is generally 0.5 to 1.0 after controlling for population growth and income, with values of almost 1.0, suggesting that new road space is totally filled by generated traffic where congestion is relatively severe. Kara Kockelman (2011), “Traffic Congestion,” Chapter 22, Transportation Engineering Handbook, McGraw Hill . ODOT asserts that it can ignore all this literature. ODOT argues, in essence, that even thought the consensus is for a unit elasticity, that here in Oregon, contra all this published literature, it believes the real coefficient of these equations is zero: that a one percent increase in roadway capacity would lead to no increase whatsoever in travel demand. In essence, the ODOT Analysis Methods Manual tells planners to ignore induced demand entirely. Latent demand is induced demand. The apparent justification for this conclusion is that there’s something called “latent” demand that’s different from “induced” demand. Oregon DOT falsely claims that there is a difference between “latent” demand and “induced” demand. Here’s what they are saying… Latent Demand – this is demand for transportation that consumers do not utilize because they cannot afford the cost or it is not currently available. Latent demand responses are typically associated with network limitations, such as capacity constraints . . . Latent demand does not include induced demand. Induced demand – new demand for travel that did not exist prior to the build scenario. This is above and beyond forecasted and latent demand associated with planned land use, it is demand that is the result of changes in land use (zone changes) or economic conditions that create new trips. (ODOT Analysis Procedures Manual, June 2022, emphasis added). Denying that “latent” demand is induced demand is not supported in the literature. No other study uses these terms in this fashion, or makes this distinction between “induced” and “latent” demand. This is ODOT’s Through the Looking Glass moment: “When I use a word,” Humpty Dumpty said, in rather a scornful tone, “it means just what I choose it to mean- neither more nor less.” Ben and Jerry observe the latent demand for ice cream every year when they drop the price of a cone to zero, and people line up around the block. These are all people who would love to have ice cream, if only it were free. The lines around the block are “induced ice cream eating”, as the zero price of ice cream converts “latent demand” into “actual demand.” But we know empirically that travel changes rapidly in response to available highway capacity. That’s true both in the case of expansions and contractions in capacity. People rapidly and radically change their travel distances and trip making in response to changes in capacity. Predicted “carmaggedons” in the face of reductions of capacity from bridge closures, highway collapses, construction projects, demolitions of highways, and other similar events cause traffic disappearance. Ultimately, this is pure sophistry: Whether you call it “latent” demand or “induced” demand, the effects are exactly the same: Adding more capacity to existing roadways increases the volume of vehicle travel. Oregon’s Analysis Procedures Manual vs. California’s Transportation Analysis Framework While OregonDOT has just published its “Analysis Procedures Manual” banning the use of induced travel calculators, its California counterpart, Caltrans has published guidelines that require the use of such a calculator to highway projects in the Golden State. What leads one state DOT to require the calculator, while the other bans it. Who is right? Let’s consider the processes and documentation that went into the CalTrans and ODOT publications. CalTrans adopted its Framework after a years-long study and review effort. It brought in outside experts, it conducted and published a thorough literature review, and the Framework itself was the subject of public meetings. As the Framework document explains: Caltrans convened an expert panel of academics and practitioners through UC Berkeley Tech Transfer. The panel chair presented the group’s conclusions to stakeholders at a virtual Technical Roundtable prior to finalizing the group’s recommendations. Caltrans and State partners have accepted the panel’s recommendations, which are reflected in the guidance documents. In contrast, the Oregon Manual has no identified author, cites no academic literature, has not been subject to outside review by persons independent from the Oregon Department of Transportation. It is an unsubstantiated, unscientific polemic. It’s also possible (and indeed likely) that even without changes in land use, households and businesses will sort themselves differently among the existing stock of land and buildings. If travel is fast and free, people may choose to live at housing a great distance from their jobs (or conversely, commute to jobs at great distance from their homes). If travel is slower or more expensive, they may seek housing nearer their job, or look for jobs only closer to home in order to minimize the time and money costs of travel. The redistribution of population and employment among existing buildings in response to changes in travel costs is something that ODOT denies is even possible. What’s deeply ironic about the denial of induced demand is that highway departments have been counting on it to create an unending demand for their services for decades. Building more and wider roads has led to more driving and more car ownership, which has jammed existing roads to capacity, and led to calls for further widening. It’s a Sisyphean cycle that leads to ever more traffic and ever more spending on roads, which is just what highway departments and their vendors want. Induced Demand and Land Use Changes As Litman points out there are first-, second-, third- and fourth-order effects from highway capacity increases. Initially travel times get faster (first order). That prompts people to change whether, when, where and by what means they travel.( second order). The shift in travel patterns and accessibility may then prompt changes in land use (third order). Finally, the cumulative effect of a shift to sprawl and greater auto dependence may further amplify trip taking (fourth-order). Roadway expansion impacts tend to include: First order. Reduced congestion delay, increased traffic speeds. Second order. Changes in time, route, destination and mode. Third order. Land use changes. More dispersed, automobile-oriented development. Fourth order. Overall increase in automobile dependency. Degraded walking and cycling conditions (due to wider roads and increased traffic volumes), reduced public transit service (due to reduced demand and associated scale economies, sometimes called the Downs-Thomson paradox), and social stigma associated with alternative modes. The ODOT view is that the “second order” effects—changing times, routes, additional trip taking, and more miles traveled—somehow don’t count as “induced travel” if no changes in land use happen. Or, alternatively, if that travel is accurately predicted by a traffic model or anticipated in a plan (i.e. “above and beyond forecasted”) , that it also doesn’t count. The Land Use Red Herring But let’s have a look at the second part of the argument: That the transportation agency can ignore that part of induced demand that results from land use changes in response to the expansion of roadways, and that somehow, because Oregon has a system of land use planning that those effects simply don’t occur here. ODOT’s rhetorical position is that “Induced demand” can only occur in response to land use changes, and land use changes are impossible under Oregon’s land use system. The Oregon Department of Transportation likes to pretend that the only form of induced travel that is real is that which accompanies changes in land use. And they argue that because Oregon has strict land use laws, that investments in travel infrastructure can’t produce changes in land use. In general, Oregon faces low risk related to induced demand because of the state’s strong land use laws, which exist to prevent sprawl. Changes to land use must be approved by local jurisdictions, so a facility project cannot induce demand just by itself. ODOT’s reasoning is this: Induced demand only occurs when there is a land use change that necessitates a change in a land use plan. Because Oregon has land use plans, transportation projects somehow can’t create induced demand. This reasoning is wrong for two reasons: First, as we’ve already explained, “latent” demand–changes in transportation behavior in response to a capacity increase–can happen even without any change in land use, and this “latent” demand is, according to all the scientific literature “induced demand.” The second reason is that Oregon’s land use law doesn’t prevent or preclude changes in land use in response to changes in transportation infrastructure. What this misses is that the land use system is a permissive framework, and within that legal framework many possible patterns of population and employment are possible. For example, new housing can be built in infill locations (near transit, and proximate to more jobs) or it can be built at the urban periphery. Both outcomes are possible under the Oregon land use system. The key point about induced demand is that more investment in transportation infrastructure will make lower density, more far flung development even more attractive. And, importantly, a significant part of the demand for Oregon roadways comes from places not subject to the Oregon land use system (i.e. suburban Clark County Washington). Investing in more transportation capacity across the Columbia River will facilitate more low density sprawl in Washington, and added automobile trips on the I-5 and I-205 bridges as large fractions of these suburban and exurban households live and shop in Oregon. A lobbying campaign to deny induced demand There’s little question that ODOT officials are uncomfortable with the science of induced travel. And they’re eager to do anything they can to minimize or misrepresent or discredit the application of this scientific fact to transportation planning. For example, in 2021, ODOT sought funding through AASHTO (the lobbying organization of state highway agencies) to get a project funded to dispute induced demand. Bike Portland reported that its proposal made it clear that the agency was primarily interested in generating talking points to push back against application of induced demand to metro area freeway expansion projects. “While the road building era of the 1950s freeway networks is essentially complete, even minor strategies and investment intended to optimize existing roadway system assets are increasingly facing opposition in the name of “induced demand”…” Even as it is busily ignoring or denying the science of induced travel, the Oregon Department of Transportation regularly repeats the discredited myth that idling in traffic is a significant source of greenhouse gas emissions that can be reduced by widening roadways. Traffic Projections that Deny Induced Travel Lack Scientific Integrity To the extent that ODOT’s guidance limits what is included in a federally required environmental impact statement, it’s steadfast refusal to cite any sources for its claims, and its consistent ignorance of published scientific literature on induced travel constitutes a violation of the scientific integrity requirements of NEPA. § 1502.23 Methodology and scientific accuracy. Agencies shall ensure the professional integrity, including scientific integrity, of the discussions and analyses in environmental documents. Agencies shall make use of reliable existing data and resources. Agencies may make use of any reliable data sources, such as remotely gathered information or statistical models. They shall identify any methodologies used and shall make explicit reference to the scientific and other sources relied upon for conclusions in the statement. Agencies may place discussion of methodology in an appendix. Agencies are not required to undertake new scientific and technical research to inform their analyses. Nothing in this section is intended to prohibit agencies from compliance with the requirements of other statutes pertaining to scientific and technical research. Chuck Marohn, writing at Strong Towns explains that traffic engineers treat travel demand as a fixed and immutable quantity–they’ve build models and a world view that pretends that people will travel just as much whether they build a project or not. This view helps justify building ever more roads, but doesn’t reflect reality and ought to be treated as professional malpractice: The concept of “travel demand” is where traffic engineers have stunted their own intellectual development more than perhaps anywhere else. And they’ve done so for two reasons. First, it makes their models easier to run. It’s really difficult (impossible, really) to create models that factor in the behavioral responses of humans. Better to just assume a static level of demand, even though that assumption is a farce (remember, traffic models are all about justifying projects, not actually modeling what is going on in the world). Second, it allows traffic planners and engineers to position themselves and their craft as responding to demand, not creating it. That’s an important distinction because it allows them to be confident in what they do without having to struggle with the underlying reasons that things aren’t working. . . . Engineering in the auto age is about building—build, build, build—and not about optimizing or managing systems. When your ethos is merely to build more stuff, you develop myths and models that support that ethos. That’s what you’re seeing in the patently absurd assertion that additional capacity does not generate more trips. . . . In 2022, denying how highway expansions induce people to drive more should be considered professional malpractice. US Secretary of Transportation Pete Buttigieg clearly endorses the science of induced demand. In a recent television interview, Buttigieg told Chris Wallace: . . . here’s an entire science to this. And we have a lot of research partners. We have our own research institution called the Volpe Institute, which is in Cambridge, Massachusetts. . . . one of the challenges we have right now is you got more and more people in the country more and more people on the road. Just how to be smart about that. For example,it turns out that sometimes when you just want to get a lot of traffic on the roadway, and you just added lanes to it, all you get is more traffic, because it actually makes more people want to drive on that road and then you’re right back where you were. Discussion blog comments powered by Disqus Related Commentary Kate: Metro’s wildly inaccurate model overstates current traffic levels The case for the $7.5 billion Interstate Bridge Replacement Project is based on traffic projections from Metro's "Kate" tr... → Joe Cortright 14.10.2024 The Interstate Bridge Project’s Flawed Traffic Data The Interstate Bridge Replacement Project simply can't tell the truth about current traffic levels or recent growth rates.... → Joe Cortright 11.10.2024 The Week Observed, August 30, 2024 What City Observatory Did This Week There's no evidence of a housing bubble. Strong Towns Chuck Marohn has a recent blo... → Joe Cortright 30.8.2024 Another housing bubble brewing? Not really Another housing bubble? Strong Towns Chuck Marohn argues that we're in the midst of another housing bubble. He claims th... → Joe Cortright 29.8.2024 City Observatory’s Joe Cortright on the Housing Bubble–2005 In an op-ed published in the Portland, Oregonian on July 17, 2005, City Observatory director Joe Cortright predicted that ... → Joe Cortright 23.8.2024 The Week Observed, August 23, 2024 What City Observatory Did This Week How Metro's RTP illegally favors driving and violates state climate rules. Oregon'... → Joe Cortright 23.8.2024 How Metro’s RTP Illegally favors car travel and violates climate rules Oregon's planning rules require Portland area transportation plans to prioritize investments that reduce vehicle miles tra... → Joe Cortright 22.8.2024 The Week Observed, August 16, 2024 Must Read Portland advocates sue to block Rose Quarter Freeway widening. There's a new chapter in the long-running batt... → Joe Cortright 7.8.2024 What Matters to the Success of Cities City Observatory Portland, Oregon info@cityobservatory.org Supported by About Commentary Reports Subjects Subscribe Search Subscribe Stay up to date by entering your email We will never sell or share your email address. ✕ Search ✕ Main Subjects Reports Commentary Subscribe Search Flat Earth Sophistry By Joe Cortright 30.12.2022 The science of induced travel is well proven, but state DOTs are in utter denial Widening freeways not only fails to reduce congestion, it inevitably results in more vehicle travel and more pollution The Oregon Department of Transportation has published a technical manual banning the consideration of induced travel in Oregon highway projects. The Oregon Department of Transportation wants to pretend that induced travel doesn’t exist. Using federal funds, it has written a new handbook on how to plan for highways that makes some preposterous and undocumented claims about the induced travel. It explicitly prohibits planners and consultants from using peer-reviewed, scientifically based tools, like the Induced Travel Calculator, developed by the University of California Sustainable Transportation Center, and mandated by the California Department of Transportation for the analysis of the environmental effects of freeways. The tortured denial by the Oregon Department of Transportation engages in some blatant sophistry that tries to create a false distinction between “latent” demand and “induced demand.” If we just call it “latent demand” then somehow it doesn’t count. Turn to page 6-79 of ODOT’s newly published “Analysis Procedures Manual“. The APM is a technical guide to using traffic data to plan future roadways. Here you find a red-bordered text box with a bold graphic STOP sign, explicitly banning planners and analysts from using the induced travel calculator. “The use of these calculator types shall not be used to estimate induced and latent demand effects on ODOT-funded projects . . . ” This kind of foot-stomping, hand-waving denial is reminiscent of the Catholic church’s harrumphing denials of Copernicus and Galileo’s observations of the universe. But induced travel is extremely well-established science, and Oregon DOT shows itself to be modern day a flat-earth science denier. What the Scientific Literature Shows The economic and scientific literature on induced travel is unambiguous: Increasing road capacity, by whatever means, lowers the perceived cost of driving and results in more travel. The phenomenon is now so well-established that its called the “Fundamental Law of Road Congestion.” The economics are straightforward: expanding the supply of highways lowers the cost of driving, and faced with a lower cost of driving, people drive more. In this classic diagram, the supply curve shifts outward (to the right) lowering the cost of driving and increasing the number of miles driven. The best available science shows that this generated travel follows a unit elasticity: a one percent increase in roadway capacity creates a one percent increase in vehicle miles traveled. To claim otherwise is to simply be in denial about the fundamental economics of the price elasticity of demand: lowering the price of something (in this case the time cost of using a particular roadway) tends to increase the volume consumed. There have been numerous studies which have all reached similar conclusions about the empirical nature of this relationship. Two of the leading scholars on the subject, the University of California’s Susan Handy and James Volker present a meta-analysis of studies of induced travel. Their results are summarized on the following table. In studies in the US and in other developed countries, there’s a strong and consistent relationship between expanded roadways and additional travel. In the long run, estimates of the elasticity of induced travel are around 1.0, meaning that a one percent increase in road capacity tends to lead to a one percent increase in vehicle miles traveled. The authoritative Traffic Engineering Handbook summarizes the literature on induced demand as follows: . . . the long-run elasticities of VMT with respect to road space is generally 0.5 to 1.0 after controlling for population growth and income, with values of almost 1.0, suggesting that new road space is totally filled by generated traffic where congestion is relatively severe. Kara Kockelman (2011), “Traffic Congestion,” Chapter 22, Transportation Engineering Handbook, McGraw Hill . ODOT asserts that it can ignore all this literature. ODOT argues, in essence, that even thought the consensus is for a unit elasticity, that here in Oregon, contra all this published literature, it believes the real coefficient of these equations is zero: that a one percent increase in roadway capacity would lead to no increase whatsoever in travel demand. In essence, the ODOT Analysis Methods Manual tells planners to ignore induced demand entirely. Latent demand is induced demand. The apparent justification for this conclusion is that there’s something called “latent” demand that’s different from “induced” demand. Oregon DOT falsely claims that there is a difference between “latent” demand and “induced” demand. Here’s what they are saying… Latent Demand – this is demand for transportation that consumers do not utilize because they cannot afford the cost or it is not currently available. Latent demand responses are typically associated with network limitations, such as capacity constraints . . . Latent demand does not include induced demand. Induced demand – new demand for travel that did not exist prior to the build scenario. This is above and beyond forecasted and latent demand associated with planned land use, it is demand that is the result of changes in land use (zone changes) or economic conditions that create new trips. (ODOT Analysis Procedures Manual, June 2022, emphasis added). Denying that “latent” demand is induced demand is not supported in the literature. No other study uses these terms in this fashion, or makes this distinction between “induced” and “latent” demand. This is ODOT’s Through the Looking Glass moment: “When I use a word,” Humpty Dumpty said, in rather a scornful tone, “it means just what I choose it to mean- neither more nor less.” Ben and Jerry observe the latent demand for ice cream every year when they drop the price of a cone to zero, and people line up around the block. These are all people who would love to have ice cream, if only it were free. The lines around the block are “induced ice cream eating”, as the zero price of ice cream converts “latent demand” into “actual demand.” But we know empirically that travel changes rapidly in response to available highway capacity. That’s true both in the case of expansions and contractions in capacity. People rapidly and radically change their travel distances and trip making in response to changes in capacity. Predicted “carmaggedons” in the face of reductions of capacity from bridge closures, highway collapses, construction projects, demolitions of highways, and other similar events cause traffic disappearance. Ultimately, this is pure sophistry: Whether you call it “latent” demand or “induced” demand, the effects are exactly the same: Adding more capacity to existing roadways increases the volume of vehicle travel. Oregon’s Analysis Procedures Manual vs. California’s Transportation Analysis Framework While OregonDOT has just published its “Analysis Procedures Manual” banning the use of induced travel calculators, its California counterpart, Caltrans has published guidelines that require the use of such a calculator to highway projects in the Golden State. What leads one state DOT to require the calculator, while the other bans it. Who is right? Let’s consider the processes and documentation that went into the CalTrans and ODOT publications. CalTrans adopted its Framework after a years-long study and review effort. It brought in outside experts, it conducted and published a thorough literature review, and the Framework itself was the subject of public meetings. As the Framework document explains: Caltrans convened an expert panel of academics and practitioners through UC Berkeley Tech Transfer. The panel chair presented the group’s conclusions to stakeholders at a virtual Technical Roundtable prior to finalizing the group’s recommendations. Caltrans and State partners have accepted the panel’s recommendations, which are reflected in the guidance documents. In contrast, the Oregon Manual has no identified author, cites no academic literature, has not been subject to outside review by persons independent from the Oregon Department of Transportation. It is an unsubstantiated, unscientific polemic. It’s also possible (and indeed likely) that even without changes in land use, households and businesses will sort themselves differently among the existing stock of land and buildings. If travel is fast and free, people may choose to live at housing a great distance from their jobs (or conversely, commute to jobs at great distance from their homes). If travel is slower or more expensive, they may seek housing nearer their job, or look for jobs only closer to home in order to minimize the time and money costs of travel. The redistribution of population and employment among existing buildings in response to changes in travel costs is something that ODOT denies is even possible. What’s deeply ironic about the denial of induced demand is that highway departments have been counting on it to create an unending demand for their services for decades. Building more and wider roads has led to more driving and more car ownership, which has jammed existing roads to capacity, and led to calls for further widening. It’s a Sisyphean cycle that leads to ever more traffic and ever more spending on roads, which is just what highway departments and their vendors want. Induced Demand and Land Use Changes As Litman points out there are first-, second-, third- and fourth-order effects from highway capacity increases. Initially travel times get faster (first order). That prompts people to change whether, when, where and by what means they travel.( second order). The shift in travel patterns and accessibility may then prompt changes in land use (third order). Finally, the cumulative effect of a shift to sprawl and greater auto dependence may further amplify trip taking (fourth-order). Roadway expansion impacts tend to include: First order. Reduced congestion delay, increased traffic speeds. Second order. Changes in time, route, destination and mode. Third order. Land use changes. More dispersed, automobile-oriented development. Fourth order. Overall increase in automobile dependency. Degraded walking and cycling conditions (due to wider roads and increased traffic volumes), reduced public transit service (due to reduced demand and associated scale economies, sometimes called the Downs-Thomson paradox), and social stigma associated with alternative modes. The ODOT view is that the “second order” effects—changing times, routes, additional trip taking, and more miles traveled—somehow don’t count as “induced travel” if no changes in land use happen. Or, alternatively, if that travel is accurately predicted by a traffic model or anticipated in a plan (i.e. “above and beyond forecasted”) , that it also doesn’t count. The Land Use Red Herring But let’s have a look at the second part of the argument: That the transportation agency can ignore that part of induced demand that results from land use changes in response to the expansion of roadways, and that somehow, because Oregon has a system of land use planning that those effects simply don’t occur here. ODOT’s rhetorical position is that “Induced demand” can only occur in response to land use changes, and land use changes are impossible under Oregon’s land use system. The Oregon Department of Transportation likes to pretend that the only form of induced travel that is real is that which accompanies changes in land use. And they argue that because Oregon has strict land use laws, that investments in travel infrastructure can’t produce changes in land use. In general, Oregon faces low risk related to induced demand because of the state’s strong land use laws, which exist to prevent sprawl. Changes to land use must be approved by local jurisdictions, so a facility project cannot induce demand just by itself. ODOT’s reasoning is this: Induced demand only occurs when there is a land use change that necessitates a change in a land use plan. Because Oregon has land use plans, transportation projects somehow can’t create induced demand. This reasoning is wrong for two reasons: First, as we’ve already explained, “latent” demand–changes in transportation behavior in response to a capacity increase–can happen even without any change in land use, and this “latent” demand is, according to all the scientific literature “induced demand.” The second reason is that Oregon’s land use law doesn’t prevent or preclude changes in land use in response to changes in transportation infrastructure. What this misses is that the land use system is a permissive framework, and within that legal framework many possible patterns of population and employment are possible. For example, new housing can be built in infill locations (near transit, and proximate to more jobs) or it can be built at the urban periphery. Both outcomes are possible under the Oregon land use system. The key point about induced demand is that more investment in transportation infrastructure will make lower density, more far flung development even more attractive. And, importantly, a significant part of the demand for Oregon roadways comes from places not subject to the Oregon land use system (i.e. suburban Clark County Washington). Investing in more transportation capacity across the Columbia River will facilitate more low density sprawl in Washington, and added automobile trips on the I-5 and I-205 bridges as large fractions of these suburban and exurban households live and shop in Oregon. A lobbying campaign to deny induced demand There’s little question that ODOT officials are uncomfortable with the science of induced travel. And they’re eager to do anything they can to minimize or misrepresent or discredit the application of this scientific fact to transportation planning. For example, in 2021, ODOT sought funding through AASHTO (the lobbying organization of state highway agencies) to get a project funded to dispute induced demand. Bike Portland reported that its proposal made it clear that the agency was primarily interested in generating talking points to push back against application of induced demand to metro area freeway expansion projects. “While the road building era of the 1950s freeway networks is essentially complete, even minor strategies and investment intended to optimize existing roadway system assets are increasingly facing opposition in the name of “induced demand”…” Even as it is busily ignoring or denying the science of induced travel, the Oregon Department of Transportation regularly repeats the discredited myth that idling in traffic is a significant source of greenhouse gas emissions that can be reduced by widening roadways. Traffic Projections that Deny Induced Travel Lack Scientific Integrity To the extent that ODOT’s guidance limits what is included in a federally required environmental impact statement, it’s steadfast refusal to cite any sources for its claims, and its consistent ignorance of published scientific literature on induced travel constitutes a violation of the scientific integrity requirements of NEPA. § 1502.23 Methodology and scientific accuracy. Agencies shall ensure the professional integrity, including scientific integrity, of the discussions and analyses in environmental documents. Agencies shall make use of reliable existing data and resources. Agencies may make use of any reliable data sources, such as remotely gathered information or statistical models. They shall identify any methodologies used and shall make explicit reference to the scientific and other sources relied upon for conclusions in the statement. Agencies may place discussion of methodology in an appendix. Agencies are not required to undertake new scientific and technical research to inform their analyses. Nothing in this section is intended to prohibit agencies from compliance with the requirements of other statutes pertaining to scientific and technical research. Chuck Marohn, writing at Strong Towns explains that traffic engineers treat travel demand as a fixed and immutable quantity–they’ve build models and a world view that pretends that people will travel just as much whether they build a project or not. This view helps justify building ever more roads, but doesn’t reflect reality and ought to be treated as professional malpractice: The concept of “travel demand” is where traffic engineers have stunted their own intellectual development more than perhaps anywhere else. And they’ve done so for two reasons. First, it makes their models easier to run. It’s really difficult (impossible, really) to create models that factor in the behavioral responses of humans. Better to just assume a static level of demand, even though that assumption is a farce (remember, traffic models are all about justifying projects, not actually modeling what is going on in the world). Second, it allows traffic planners and engineers to position themselves and their craft as responding to demand, not creating it. That’s an important distinction because it allows them to be confident in what they do without having to struggle with the underlying reasons that things aren’t working. . . . Engineering in the auto age is about building—build, build, build—and not about optimizing or managing systems. When your ethos is merely to build more stuff, you develop myths and models that support that ethos. That’s what you’re seeing in the patently absurd assertion that additional capacity does not generate more trips. . . . In 2022, denying how highway expansions induce people to drive more should be considered professional malpractice. US Secretary of Transportation Pete Buttigieg clearly endorses the science of induced demand. In a recent television interview, Buttigieg told Chris Wallace: . . . here’s an entire science to this. And we have a lot of research partners. We have our own research institution called the Volpe Institute, which is in Cambridge, Massachusetts. . . . one of the challenges we have right now is you got more and more people in the country more and more people on the road. Just how to be smart about that. For example,it turns out that sometimes when you just want to get a lot of traffic on the roadway, and you just added lanes to it, all you get is more traffic, because it actually makes more people want to drive on that road and then you’re right back where you were. Discussion blog comments powered by Disqus Related Commentary Kate: Metro’s wildly inaccurate model overstates current traffic levels The case for the $7.5 billion Interstate Bridge Replacement Project is based on traffic projections from Metro's "Kate" tr... → Joe Cortright 14.10.2024 The Interstate Bridge Project’s Flawed Traffic Data The Interstate Bridge Replacement Project simply can't tell the truth about current traffic levels or recent growth rates.... → Joe Cortright 11.10.2024 The Week Observed, August 30, 2024 What City Observatory Did This Week There's no evidence of a housing bubble. Strong Towns Chuck Marohn has a recent blo... → Joe Cortright 30.8.2024 Another housing bubble brewing? Not really Another housing bubble? Strong Towns Chuck Marohn argues that we're in the midst of another housing bubble. He claims th... → Joe Cortright 29.8.2024 City Observatory’s Joe Cortright on the Housing Bubble–2005 In an op-ed published in the Portland, Oregonian on July 17, 2005, City Observatory director Joe Cortright predicted that ... → Joe Cortright 23.8.2024 The Week Observed, August 23, 2024 What City Observatory Did This Week How Metro's RTP illegally favors driving and violates state climate rules. Oregon'... → Joe Cortright 23.8.2024 How Metro’s RTP Illegally favors car travel and violates climate rules Oregon's planning rules require Portland area transportation plans to prioritize investments that reduce vehicle miles tra... → Joe Cortright 22.8.2024 The Week Observed, August 16, 2024 Must Read Portland advocates sue to block Rose Quarter Freeway widening. There's a new chapter in the long-running batt... → Joe Cortright 7.8.2024 What Matters to the Success of Cities City Observatory Portland, Oregon info@cityobservatory.org Supported by About Commentary Reports Subjects Subscribe Search ✕ Search ✕ Main Subjects Reports Commentary Subscribe Search Flat Earth Sophistry By Joe Cortright 30.12.2022 The science of induced travel is well proven, but state DOTs are in utter denial Widening freeways not only fails to reduce congestion, it inevitably results in more vehicle travel and more pollution The Oregon Department of Transportation has published a technical manual banning the consideration of induced travel in Oregon highway projects. The Oregon Department of Transportation wants to pretend that induced travel doesn’t exist. Using federal funds, it has written a new handbook on how to plan for highways that makes some preposterous and undocumented claims about the induced travel. It explicitly prohibits planners and consultants from using peer-reviewed, scientifically based tools, like the Induced Travel Calculator, developed by the University of California Sustainable Transportation Center, and mandated by the California Department of Transportation for the analysis of the environmental effects of freeways. The tortured denial by the Oregon Department of Transportation engages in some blatant sophistry that tries to create a false distinction between “latent” demand and “induced demand.” If we just call it “latent demand” then somehow it doesn’t count. Turn to page 6-79 of ODOT’s newly published “Analysis Procedures Manual“. The APM is a technical guide to using traffic data to plan future roadways. Here you find a red-bordered text box with a bold graphic STOP sign, explicitly banning planners and analysts from using the induced travel calculator. “The use of these calculator types shall not be used to estimate induced and latent demand effects on ODOT-funded projects . . . ” This kind of foot-stomping, hand-waving denial is reminiscent of the Catholic church’s harrumphing denials of Copernicus and Galileo’s observations of the universe. But induced travel is extremely well-established science, and Oregon DOT shows itself to be modern day a flat-earth science denier. What the Scientific Literature Shows The economic and scientific literature on induced travel is unambiguous: Increasing road capacity, by whatever means, lowers the perceived cost of driving and results in more travel. The phenomenon is now so well-established that its called the “Fundamental Law of Road Congestion.” The economics are straightforward: expanding the supply of highways lowers the cost of driving, and faced with a lower cost of driving, people drive more. In this classic diagram, the supply curve shifts outward (to the right) lowering the cost of driving and increasing the number of miles driven. The best available science shows that this generated travel follows a unit elasticity: a one percent increase in roadway capacity creates a one percent increase in vehicle miles traveled. To claim otherwise is to simply be in denial about the fundamental economics of the price elasticity of demand: lowering the price of something (in this case the time cost of using a particular roadway) tends to increase the volume consumed. There have been numerous studies which have all reached similar conclusions about the empirical nature of this relationship. Two of the leading scholars on the subject, the University of California’s Susan Handy and James Volker present a meta-analysis of studies of induced travel. Their results are summarized on the following table. In studies in the US and in other developed countries, there’s a strong and consistent relationship between expanded roadways and additional travel. In the long run, estimates of the elasticity of induced travel are around 1.0, meaning that a one percent increase in road capacity tends to lead to a one percent increase in vehicle miles traveled. The authoritative Traffic Engineering Handbook summarizes the literature on induced demand as follows: . . . the long-run elasticities of VMT with respect to road space is generally 0.5 to 1.0 after controlling for population growth and income, with values of almost 1.0, suggesting that new road space is totally filled by generated traffic where congestion is relatively severe. Kara Kockelman (2011), “Traffic Congestion,” Chapter 22, Transportation Engineering Handbook, McGraw Hill . ODOT asserts that it can ignore all this literature. ODOT argues, in essence, that even thought the consensus is for a unit elasticity, that here in Oregon, contra all this published literature, it believes the real coefficient of these equations is zero: that a one percent increase in roadway capacity would lead to no increase whatsoever in travel demand. In essence, the ODOT Analysis Methods Manual tells planners to ignore induced demand entirely. Latent demand is induced demand. The apparent justification for this conclusion is that there’s something called “latent” demand that’s different from “induced” demand. Oregon DOT falsely claims that there is a difference between “latent” demand and “induced” demand. Here’s what they are saying… Latent Demand – this is demand for transportation that consumers do not utilize because they cannot afford the cost or it is not currently available. Latent demand responses are typically associated with network limitations, such as capacity constraints . . . Latent demand does not include induced demand. Induced demand – new demand for travel that did not exist prior to the build scenario. This is above and beyond forecasted and latent demand associated with planned land use, it is demand that is the result of changes in land use (zone changes) or economic conditions that create new trips. (ODOT Analysis Procedures Manual, June 2022, emphasis added). Denying that “latent” demand is induced demand is not supported in the literature. No other study uses these terms in this fashion, or makes this distinction between “induced” and “latent” demand. This is ODOT’s Through the Looking Glass moment: “When I use a word,” Humpty Dumpty said, in rather a scornful tone, “it means just what I choose it to mean- neither more nor less.” Ben and Jerry observe the latent demand for ice cream every year when they drop the price of a cone to zero, and people line up around the block. These are all people who would love to have ice cream, if only it were free. The lines around the block are “induced ice cream eating”, as the zero price of ice cream converts “latent demand” into “actual demand.” But we know empirically that travel changes rapidly in response to available highway capacity. That’s true both in the case of expansions and contractions in capacity. People rapidly and radically change their travel distances and trip making in response to changes in capacity. Predicted “carmaggedons” in the face of reductions of capacity from bridge closures, highway collapses, construction projects, demolitions of highways, and other similar events cause traffic disappearance. Ultimately, this is pure sophistry: Whether you call it “latent” demand or “induced” demand, the effects are exactly the same: Adding more capacity to existing roadways increases the volume of vehicle travel. Oregon’s Analysis Procedures Manual vs. California’s Transportation Analysis Framework While OregonDOT has just published its “Analysis Procedures Manual” banning the use of induced travel calculators, its California counterpart, Caltrans has published guidelines that require the use of such a calculator to highway projects in the Golden State. What leads one state DOT to require the calculator, while the other bans it. Who is right? Let’s consider the processes and documentation that went into the CalTrans and ODOT publications. CalTrans adopted its Framework after a years-long study and review effort. It brought in outside experts, it conducted and published a thorough literature review, and the Framework itself was the subject of public meetings. As the Framework document explains: Caltrans convened an expert panel of academics and practitioners through UC Berkeley Tech Transfer. The panel chair presented the group’s conclusions to stakeholders at a virtual Technical Roundtable prior to finalizing the group’s recommendations. Caltrans and State partners have accepted the panel’s recommendations, which are reflected in the guidance documents. In contrast, the Oregon Manual has no identified author, cites no academic literature, has not been subject to outside review by persons independent from the Oregon Department of Transportation. It is an unsubstantiated, unscientific polemic. It’s also possible (and indeed likely) that even without changes in land use, households and businesses will sort themselves differently among the existing stock of land and buildings. If travel is fast and free, people may choose to live at housing a great distance from their jobs (or conversely, commute to jobs at great distance from their homes). If travel is slower or more expensive, they may seek housing nearer their job, or look for jobs only closer to home in order to minimize the time and money costs of travel. The redistribution of population and employment among existing buildings in response to changes in travel costs is something that ODOT denies is even possible. What’s deeply ironic about the denial of induced demand is that highway departments have been counting on it to create an unending demand for their services for decades. Building more and wider roads has led to more driving and more car ownership, which has jammed existing roads to capacity, and led to calls for further widening. It’s a Sisyphean cycle that leads to ever more traffic and ever more spending on roads, which is just what highway departments and their vendors want. Induced Demand and Land Use Changes As Litman points out there are first-, second-, third- and fourth-order effects from highway capacity increases. Initially travel times get faster (first order). That prompts people to change whether, when, where and by what means they travel.( second order). The shift in travel patterns and accessibility may then prompt changes in land use (third order). Finally, the cumulative effect of a shift to sprawl and greater auto dependence may further amplify trip taking (fourth-order). Roadway expansion impacts tend to include: First order. Reduced congestion delay, increased traffic speeds. Second order. Changes in time, route, destination and mode. Third order. Land use changes. More dispersed, automobile-oriented development. Fourth order. Overall increase in automobile dependency. Degraded walking and cycling conditions (due to wider roads and increased traffic volumes), reduced public transit service (due to reduced demand and associated scale economies, sometimes called the Downs-Thomson paradox), and social stigma associated with alternative modes. The ODOT view is that the “second order” effects—changing times, routes, additional trip taking, and more miles traveled—somehow don’t count as “induced travel” if no changes in land use happen. Or, alternatively, if that travel is accurately predicted by a traffic model or anticipated in a plan (i.e. “above and beyond forecasted”) , that it also doesn’t count. The Land Use Red Herring But let’s have a look at the second part of the argument: That the transportation agency can ignore that part of induced demand that results from land use changes in response to the expansion of roadways, and that somehow, because Oregon has a system of land use planning that those effects simply don’t occur here. ODOT’s rhetorical position is that “Induced demand” can only occur in response to land use changes, and land use changes are impossible under Oregon’s land use system. The Oregon Department of Transportation likes to pretend that the only form of induced travel that is real is that which accompanies changes in land use. And they argue that because Oregon has strict land use laws, that investments in travel infrastructure can’t produce changes in land use. In general, Oregon faces low risk related to induced demand because of the state’s strong land use laws, which exist to prevent sprawl. Changes to land use must be approved by local jurisdictions, so a facility project cannot induce demand just by itself. ODOT’s reasoning is this: Induced demand only occurs when there is a land use change that necessitates a change in a land use plan. Because Oregon has land use plans, transportation projects somehow can’t create induced demand. This reasoning is wrong for two reasons: First, as we’ve already explained, “latent” demand–changes in transportation behavior in response to a capacity increase–can happen even without any change in land use, and this “latent” demand is, according to all the scientific literature “induced demand.” The second reason is that Oregon’s land use law doesn’t prevent or preclude changes in land use in response to changes in transportation infrastructure. What this misses is that the land use system is a permissive framework, and within that legal framework many possible patterns of population and employment are possible. For example, new housing can be built in infill locations (near transit, and proximate to more jobs) or it can be built at the urban periphery. Both outcomes are possible under the Oregon land use system. The key point about induced demand is that more investment in transportation infrastructure will make lower density, more far flung development even more attractive. And, importantly, a significant part of the demand for Oregon roadways comes from places not subject to the Oregon land use system (i.e. suburban Clark County Washington). Investing in more transportation capacity across the Columbia River will facilitate more low density sprawl in Washington, and added automobile trips on the I-5 and I-205 bridges as large fractions of these suburban and exurban households live and shop in Oregon. A lobbying campaign to deny induced demand There’s little question that ODOT officials are uncomfortable with the science of induced travel. And they’re eager to do anything they can to minimize or misrepresent or discredit the application of this scientific fact to transportation planning. For example, in 2021, ODOT sought funding through AASHTO (the lobbying organization of state highway agencies) to get a project funded to dispute induced demand. Bike Portland reported that its proposal made it clear that the agency was primarily interested in generating talking points to push back against application of induced demand to metro area freeway expansion projects. “While the road building era of the 1950s freeway networks is essentially complete, even minor strategies and investment intended to optimize existing roadway system assets are increasingly facing opposition in the name of “induced demand”…” Even as it is busily ignoring or denying the science of induced travel, the Oregon Department of Transportation regularly repeats the discredited myth that idling in traffic is a significant source of greenhouse gas emissions that can be reduced by widening roadways. Traffic Projections that Deny Induced Travel Lack Scientific Integrity To the extent that ODOT’s guidance limits what is included in a federally required environmental impact statement, it’s steadfast refusal to cite any sources for its claims, and its consistent ignorance of published scientific literature on induced travel constitutes a violation of the scientific integrity requirements of NEPA. § 1502.23 Methodology and scientific accuracy. Agencies shall ensure the professional integrity, including scientific integrity, of the discussions and analyses in environmental documents. Agencies shall make use of reliable existing data and resources. Agencies may make use of any reliable data sources, such as remotely gathered information or statistical models. They shall identify any methodologies used and shall make explicit reference to the scientific and other sources relied upon for conclusions in the statement. Agencies may place discussion of methodology in an appendix. Agencies are not required to undertake new scientific and technical research to inform their analyses. Nothing in this section is intended to prohibit agencies from compliance with the requirements of other statutes pertaining to scientific and technical research. Chuck Marohn, writing at Strong Towns explains that traffic engineers treat travel demand as a fixed and immutable quantity–they’ve build models and a world view that pretends that people will travel just as much whether they build a project or not. This view helps justify building ever more roads, but doesn’t reflect reality and ought to be treated as professional malpractice: The concept of “travel demand” is where traffic engineers have stunted their own intellectual development more than perhaps anywhere else. And they’ve done so for two reasons. First, it makes their models easier to run. It’s really difficult (impossible, really) to create models that factor in the behavioral responses of humans. Better to just assume a static level of demand, even though that assumption is a farce (remember, traffic models are all about justifying projects, not actually modeling what is going on in the world). Second, it allows traffic planners and engineers to position themselves and their craft as responding to demand, not creating it. That’s an important distinction because it allows them to be confident in what they do without having to struggle with the underlying reasons that things aren’t working. . . . Engineering in the auto age is about building—build, build, build—and not about optimizing or managing systems. When your ethos is merely to build more stuff, you develop myths and models that support that ethos. That’s what you’re seeing in the patently absurd assertion that additional capacity does not generate more trips. . . . In 2022, denying how highway expansions induce people to drive more should be considered professional malpractice. US Secretary of Transportation Pete Buttigieg clearly endorses the science of induced demand. In a recent television interview, Buttigieg told Chris Wallace: . . . here’s an entire science to this. And we have a lot of research partners. We have our own research institution called the Volpe Institute, which is in Cambridge, Massachusetts. . . . one of the challenges we have right now is you got more and more people in the country more and more people on the road. Just how to be smart about that. For example,it turns out that sometimes when you just want to get a lot of traffic on the roadway, and you just added lanes to it, all you get is more traffic, because it actually makes more people want to drive on that road and then you’re right back where you were.

Highway Robbery Government highway agencies have enabled the blatant falsification of traffic model results. As a result, the United States wastes billions on road expansions that fail to cure congestion and make it harder to get around without a car. DISSENT, October 2024 https://www.dissentmagazine.org/online_articles/highway-robbery/ Benjamin Ross and Joseph Cortright ▪ October 10, 2024 Traffic on I-395 in Washington, D.C. (Kevin Dietsch/Getty Images) In 1996, the state highway agencies of Kentucky and Indiana set out to build a new bridge over the Ohio River, adding more lanes to Interstate 65 where it leaves downtown Louisville. Their planners employed an elaborate computer model to forecast future traffic volumes. The model predicted that by 2025, 160,000 cars would cross the old and new bridges on an average weekday. Based on that forecast, the states decided to make the new bridge six lanes wide. When it finally opened, in 2016, the project had cost more than a billion dollars. In 2023, just 70,000 cars crossed the two adjoining bridges on an average day. The model was wrong, but it did its job for the highway agencies: they got to spend all that money on the new bridge. Highway construction is a very big business. Nationally, the United States spends nearly $150 billion per year on road and highway construction, an amount that has increased by almost 50 percent in the past five years. The highway-building bureaucracy has created a powerful and well-organized political machine that mobilizes construction companies, engineering firms, truckers, and local business boosters. Politicians are always keen to take credit at ribbon-cuttings. Highway departments routinely shortchange maintenance to cobble together funding for massive empire-building highway and bridge projects. In pursuit of these goals, highway agencies depend on traffic models. These models are bewilderingly complex, their results are offered with false certainty, and when they are challenged in court, judges routinely defer to “agency expertise.” To understand how these impenetrable models work, let alone contest their accuracy or validity, is a daunting task. The models thus serve as powerful technocratic weapons in securing funding, dismissing environmental concerns, and blocking outside scrutiny. Concrete keeps pouring into new highway lanes, regardless of their utility for drivers or their damage to the world around them. Bad Science The National Environmental Policy Act, passed in 1970, requires highway builders to assess environmental impacts before an interstate highway can be built or expanded. These assessments hinge directly on estimates of future traffic levels. The forecasters, usually employees or consultants for the state highway agency, use models developed by regional planning organizations. Established by federal law in each metropolitan area, the regional planners are theoretically independent of the highway agencies, but in practice are usually under their thumb. The models divide the region into areas of a few thousand inhabitants each, called Traffic Analysis Zones. The model starts from the number of residents in each zone and the locations of their jobs, both currently and as predicted for a “forecast year” twenty or thirty years in the future. The model then finds the optimum route for each trip to work, balancing travel time against tolls or transit fares. Non-commuting trips, like those for shopping, trucking, and through travel by long-distance drivers, are added in as well. These models need a vast amount of data about current travel patterns, much of which can only be estimated. Extrapolating such data decades into the future creates further potential for error and manipulation. Dealing with congested roads piles on mathematical difficulties: when traffic backs up, traffic speed at one location depends on traffic volume elsewhere. Whether a given route is fastest for one driver depends on how many other commuters choose to drive that route. Highway builders take advantage of this complexity, presenting models to the public as black boxes that only experts understand. Key assumptions are not disclosed. It’s not news that powerful economic interests can pervert science. The cases of climate change, tobacco, asbestos, and lead are only the most notorious examples. Research is kept in friendly hands so that dangers are known only to the manufacturers (asbestos), or even better, remain undiscovered (leaded gasoline). When that fails, companies manufacture doubt by sponsoring a cadre of friendly researchers who slant studies to yield desired results (cigarettes, global warming). For all their faults, industry-backed researchers in those fields generally avoided flat-out falsification of study results. The highway agencies, however, have taken the perversion of science to a new level. Until recently, lack of transparency shielded the inner workings of the modeling process from public view. But two recent investigations, one by each author of this article, managed to get behind the curtain. Both revealed blatant falsification of model results. When forecasters were disappointed by the computer outputs, the forecasters simply changed them by hand, passing off the doctored numbers as genuine results of the model. The practice of manually altering the results of calculations turns out to be widespread, and the Federal Highway Administration, which should police the modelers, has given it a wink and a nod. The I-5 Columbia River Bridge Since 2004, the Oregon and Washington State Departments of Transportation have been promoting a five-mile-long, ten-lane, $7.5 billion bridge and highway expansion on I-5 across the Columbia River between Portland and Vancouver, Washington. The Interstate Bridge Replacement project, previously branded the Columbia River Crossing, has been touted for two decades—long enough to bring to light fundamental flaws in the project’s traffic modeling. The project’s claimed rationale, repeated despite years of evidence to the contrary, is that traffic volumes across the river will grow rapidly, creating intolerable congestion if nothing is done. In 2005, state highway officials predicted that in the “no-build case”—the scenario if the project is not built—traffic would grow 1.3 percent per year for the next two decades. In reality, traffic growth from 2005 to 2019 averaged just 0.3 percent per year. The travel demand models overstated actual growth by a factor of four—a mistake that current forecasts still repeat. The state DOTs presented their traffic projections for the revived project as the findings of a regional travel demand model. But rather than use the model’s outputs, the project’s consultants altered them, inflating predicted rush-hour volumes to falsely support the need for a wider roadway. Local advocates—including Joseph Cortright, co-author of this article—were only able to obtain the actual model results under state public records laws. Comparing the actual outputs to the DOTs’ published forecast showed that project consultants had systematically altered numbers to favor the proposed project and minimize environmental impacts. These changes made “no-build” traffic volumes look larger, and congestion vastly worse, than the model had predicted. Moreover, consultants failed to show their work so that outsiders could check the validity of the alterations. When the changes were discovered, the DOTs justified them as “post-processing.” Post-processing is a real part of modeling, used in many fields to describe an auxiliary computer program that puts the numerical output of a simulation model into a form understandable by humans or by another computer program. Typical post-processing operations include graphing, interpolation, unit conversion, or smoothing to remove numerical noise. But crucially, genuine post-processing does not alter the findings of the simulation model. Maryland Toll Lanes In September 2017, Maryland Governor Larry Hogan announced a grandiose plan to widen nearly 100 miles of highways around Washington, D.C., by adding privatized toll lanes. The proposal was hotly contested from the start, and due in part to grassroots opposition, was repeatedly scaled back in the years after Hogan’s initial announcement. Just as the Maryland DOT was winding up its draft environmental study, the D.C.-area Transportation Planning Board issued a new version of its traffic model. Maryland had already done its analysis using the previous model, so it ran the new model for the no-build case to confirm that the two versions yielded similar results. The comparison was included in the draft report, published in October 2020. A few months later, the project shrank once again, down to a thirteen-mile stretch across the Potomac River on Washington’s famous Beltway and continuing northward on I-270. A supplement to the draft environmental report, issued in October 2021, stated that its forecasts for both build and no-build cases were based on the regional planning board’s newer model version. Notably, the supplement predicted traffic volumes in the no-build case that were substantially different, by as much as 10 percent, from the traffic predicted by the same model in the previous report. Yet the model had only been run once—a fact never mentioned in the report. Not until two years later, after a contentious fight under the Public Information Act, was it revealed that Maryland DOT had attributed two different sets of numbers to the same model run. There were manifest errors in the October 2021 forecast. It predicted, for example, that widening highways west of Washington would substantially reduce traffic toward Baltimore and Annapolis on the northeast side of the city. Co-author Benjamin Ross and other opponents of the toll lanes wrote to the Federal Highway Administration, pointing out that the model had to be flawed to produce such patently incorrect predictions. We asked for the model to be fixed and the report redone. The final environmental report, with a new traffic forecast, appeared the following June. The anomalies identified the previous October had been corrected, but the traffic volumes had also been changed, in ways no computer model could have produced. On July 11, 2022, three weeks before final federal approval of the project was expected, Ross requested an investigation into possible scientific fraud, attracting media attention. On August 11, this request and Maryland DOT’s reply were referred to specialists at the Volpe Center, a federal transportation research organization in Cambridge, Massachusetts. Just four days later Volpe responded, saying that while manual adjustments to model outputs are sometimes necessary, the Maryland modelers had not explained their adjustments and therefore Volpe could not “assess their plausibility or validity.” Meanwhile, the scheduled August 5 federal signoff date had passed. Governor Hogan, who had hoped to put the toll lanes at the center of a possible presidential campaign, was furious at the delay. Calling it “outrageous and shocking,” he wrote to President Joe Biden to demand immediate action, and threatened a lawsuit if it were not forthcoming. Federal approval came on August 25. The Maryland DOT press release announcing the decision blatantly misrepresented the Volpe Center’s findings: “USDOT Independent Review Finds No ‘Scientific Fraud’ in Toll Lane Traffic Model,” the headline declared. Deep in the fine print of the approval document, however, in the legend of a figure on page twenty of Appendix D, the Maryland DOT admitted to the public for the first time that it had manually changed traffic model outputs. In all, we now know, it had published three substantially different sets of numbers and attributed all of them to a single model run. A Common Practice Exaggeration of traffic growth is endemic to the highway engineering profession. Researcher Tony Dutzik reviewed two decades of predictions of automobile usage by state transportation departments, the Federal Highway Administration, and industry groups. In nearly every case, Dutzik found, actual traffic volumes grew substantially more slowly than forecasted. Predictions for individual highways ran even farther off base. In the decade since the Ohio and Kentucky highway departments began pushing to expand the Brent Spence Bridge connecting Cincinnati and Covington, Kentucky, ostensibly to serve the future traffic increases predicted by the agencies’ models, traffic levels on the bridge have in fact gone down. Nonetheless they are proceeding with a $3.6 billion project to almost double the size of the bridge. Again and again, critics such as traffic engineering consultant Norm Marshall find highway agencies ignoring real growth trends and capacity constraints to overstate projected traffic congestion. The predicted no-build congestion is exaggerated; the environmental damage from the added traffic that the wider road will attract is minimized. Building these unrealistic assumptions into traffic models serves the interests of highway builders. But the rot goes deeper. Much evidence suggests that the practice of altering model results, as uncovered in Oregon and Maryland, is widespread. In an informal survey last summer, modelers from seven states told the advocacy group Transportation for America that their organizations alter outputs manually based on “engineering judgment” or “long-range trends” as part of their post-processing. Similar reports come from former employees of highway agencies elsewhere. To be clear, simulation modeling need not be done purely by computers. In proper circumstances, the computer output can be combined with other numbers: for example, if a traffic model only simulates the movement of passenger cars, trucks are estimated manually and added to get the total traffic volume. But without a quantitative basis, such changes are mere opinion, not modeling. Concealing alterations to portray manually adjusted numbers as the outputs of an impartial computer model is scientific fraud. Many younger traffic engineers are troubled by these practices. Last year, California Department of Transportation Deputy Director Jeanie Ward-Waller filed a whistleblower complaint over the agency’s plans to illegally divert maintenance funding and avoid environmental reviews to widen a stretch of I-80 between Sacramento and Davis. Shortly afterward, Caltrans (as the agency is known) fired Ward-Waller, who is now suing the department for illegal retaliation. Caltrans continues to push ahead with the project, despite opposition from the state’s air pollution regulators. The California Air Resources Board had taken the extraordinary step of debunking Caltrans traffic modeling, which claims that the highway will generate fewer vehicle miles of travel and less pollution if it is widened than if it is not. Why the Falsification? If even malignant economic interests such as cigarette and asbestos manufacturers rarely resorted to flat-out falsification of results, why is it so common in traffic modeling? Part of the answer lies in the environmental legislation that requires highway agencies to come up with traffic forecasts. It’s not enough for them to suppress bad results; they must manufacture good ones. Another factor is the models’ sheer complexity. Most model users rely on computer programs and input data developed by others. To cook the books by changing algorithms or inputs would require coordinating a team of people across multiple organizations; it is much simpler to just change the answers. There are even deeper problems. Even when results aren’t blatantly falsified, they are distorted by inherent biases and shortcomings. Despite their complexity, models omit two basic processes that determine traffic volumes on congested highways. First, they assume drivers always react to congestion by taking a different route. Second, they ignore the limited physical capacity of a highway and don’t consider the spreading of traffic jams beyond the bottlenecks that cause them. When a car trip takes more time or costs more money, some people walk, cycle, carpool, or choose not to take the trip. Others shift their schedules to avoid rush hour. Over time, people move or change jobs. If a highway is widened to speed up traffic, the missing traffic will return, and job and home relocations will create new traffic. The models in current use are unable to count the drivers waiting in the wings, let alone predict how the number of cars on the road will vary as congestion gets better or worse. As a result, the models often fail when trying to analyze congested roadways. On top of that, the spatial structure of the models, based on Traffic Analysis Zones, blurs detail. Traffic is not divided accurately among nearby roads. The user’s guide for at least one regional model even warns against using it to predict traffic on individual roads, before going on to say that it will be used in just that way. With these weaknesses, models tend to depart from reality even when used with the best intentions. When they fail even to reproduce current traffic conditions, as often happens, modelers introduce fudge factors to create a match, which in turn makes them less sensitive to future changes. Algorithms pushed far outside their realm of applicability spew out nonsense. Modelers replace the nonsense with their own best guesses and call what they’ve done post-processing. From there it’s a short step to altering results to please the boss. Indeed, the best possible forecast may be one that forgoes elaborate computations altogether: in crowded urban areas, traffic congestion will remain the same, whether highways get wider or narrower. This prediction is far from perfect; no one doubts, for instance, that widening a highway at a bottleneck point can move the traffic jam elsewhere. But in our experience, it is substantially more accurate on average than current traffic modeling. The Columbia River bridge story is typical. Modelers two decades ago predicted growing delays unless something were done; but as the widening project has languished, traffic volumes have barely changed. Tearing down San Francisco’s Embarcadero Freeway after a 1989 earthquake made downtown traffic no worse than before. An extreme example is I-405 in Los Angeles, where a carpool lane was added to a ten-mile stretch of highway through the mountains west of Beverly Hills, at a cost of a billion dollars. This was supposed to cut ten minutes off commuting times. But after the new lane opened in 2014, the drive took a minute longer than the year before. There is, of course, no need to feed data into a computer if your model always predicts that traffic will move at the same speed twenty years hence as it moves now. Scientifically, a simpler model is a better model. But for highway agencies building a case for larger roads and more expensive projects, such a model would be a disaster. They need to predict worse traffic if the highway isn’t widened and better if it is, and to fend off criticism by obscuring the basis for these predictions in a fog of complexity. By contrast, the last thing the highway agencies want to consider is the one proven way to reduce traffic congestion: charging tolls on existing highways. Such tolls are the reason the Louisville bridges carry fewer cars than they did years ago. (The modelers took the tolls into account, but wildly underestimated their effect in discouraging traffic.) As this example shows, charging a toll high enough to pay for a new bridge will often reduce traffic so much that there’s no reason to build the bridge at all—a fact that explains highway agencies’ widespread resistance to tolling for congestion relief. Until recently, New York City was poised to use tolls to relieve the traffic jams that have plagued Lower Manhattan for a century. New York stopped adding road capacity decades ago, and much street space has since been converted into bus and bike lanes, parks, and outdoor dining space. In that time, the city has gained more than a million residents and jobs with little effect on traffic congestion, while two-thirds of all trips are now on foot, on bicycle, or by transit. The overwhelmingly negative reaction to Governor Kathy Hochul’s decision to abort congestion pricing shows the growing support for managing traffic congestion by limiting automobile use instead of making more room for cars. Traffic modeling, as now practiced, spreads a pseudoscientific veneer over highway engineers’ and contractors’ never-ending quest for ever-larger roads. The demonstrated inaccuracy of current methods is persistently and willfully disregarded, while “post-processing” results to fit a preferred narrative is all too common. The United States keeps wasting billions on road expansions that not only fail to cure congestion, but also make it ever harder to get around without a car. The outcome is more driving, more pollution, more climate-warming gases—and more traffic jams to boot. Benjamin Ross, a longtime Dissent contributor, is chair of the Maryland Transit Opportunities Coalition. Joseph Cortright is the director of City Observatory in Portland, Oregon

IBR: Forecasting the impossible By Joe Cortright 16.10.2024 The case for the $7.5 billion Interstate Bridge Replacement project is based on deeply flawed traffic models that ignore the bridge’s capacity limits, and predict plainly unrealistic levels of traffic growth if the bridge isn’t expanded. These grossly overestimated projections make future traffic look worse and overstate the need and understate the environmental and financial costs associated with freeway expansion. The current I-5 bridge can carry no more than 5,000 vehicles northbound in the afternoon peak hour. All of the available statistics, and every one of the experts that has looked at the bridge has concluded that it is already operating at its maximum capacity. But, Metro’s regional travel demand model, Kate, pretends that the bridge now carries more than 6,200 vehicles per hour–a thousand more cars and trucks per hour than can actually fit across the bridge. And the Kate model, used for the IBR environmental analysis, makes the absurd prediction that peak hour PM traffic will increase further beyond its capacity—even if the IBR project isn’t built. And IBR officials altered the outputs of the Metro model to produce an event higher—and more preposterous–prediction that the “No-Build” version of the bridge would somehow carry 6,900 vehicles per hour in the northbound peak in 2045. Forecasting the impossible IBR traffic modeling is blind to the real capacity limits on the I-5 bridges; this is a common flaw in the kind of “static traffic assignment” models that Metro and IBR used; Models that don’t accurately account for capacity limits are broken, and worthless for analyzing traffic conditions and deciding how to spend billions of dollars. But the Oregon and Washington highway departments have chosen to use these flawed models to sell an oversized bridge. These over-estimates-pretending that traffic volumes wildly exceed actual capacity are a critical gimmick for falsely portraying what happens if the $7.5 billion Interstate Bridge Replacement Project isn’t built. They’re critically a way of hiding the “induced travel” that will come if the bridge is expanded: by pretending that traffic will increase whether or not the I-5 highway is widened, IBR officials are concealing the pollution and traffic that comes from wider roadways. The decision to use a traffic model that ignores the capacity constraints on the existing I-5 bridges exaggerates future traffic growth and congestion, and falsely conceals the negative environmental effects associated with a wider crossing. Using an inaccurate, unscientific model, blatantly violates the National Environmental Policy Act. The most obvious feature of the existing I-5 bridges over the Columbia River is the two narrow three-lane wide structures that carry highway from bank to bank. There are just so many vehicles that can be fitted into these lanes. The traffic data–confirmed by every expert that has looked at the bridge–is that the maximum peak hour capacity of the bridge has been reached, and can’t increase further. For example, afternoon peak hour crossings on the bridge have been stuck at less than 5,000 vehicles per hour for the past two decades. In spite of this obvious and well-documented limitation, Metro’s Kate travel demand model, which is the basis for the IBR’s environmental analysis, asserts that even if nothing is done, more and more cars will cross the bridge at the peak hour each year. In fact, as we’ve documented previously, Metro’s Kate model—the basis for IBR traffic projections–simply fails to correctly estimate even the current levels of traffic on the I-5 bridges, assigning nearly 20,000 more daily trips to the bridges than they actually carry. The problem of these over-estimated volumes is most acute for the peak hour. Metro’s Kate model over-estimates the current level of traffic on the bridge–asserting that it carries over 6,000 vehicles per hour in the Northbound PM peak, even though traffic data show that flows are always less than 5,000 vehicles per hour. The problem here is that Metro’s model simply fails to realistically account for the physical limits on traffic flow on the bridge. The model creates a fictional alternative reality where the bridge somehow carries more and more peak hour traffic–even though the data, and the modelers themselves admit the bridge has long since reached its capacity. Metro’s flawed Kate Traffic model predicts traffic exceeding capacity–an impossible outcome. That inflated “no-build” estimate is a critical foundation of the phony case being made for expanding the I-5 bridges. By exaggerating peak hour growth if nothing is done, the model makes it appear that traffic will be worse than it will actually ever be. In addition, because environmental analyses use this exaggerated no-build traffic level (and resulting pollution) as their basis for comparison, they create the false perception that the “build” alternatives (which add massive amounts of road capacity) won’t stimulate additional trips, vehicle miles of travel, and pollution. The Interstate Bridge Replacement (IBR) project, with its multi-billion dollar price tag, is founded on traffic projections that defy physical reality. This discrepancy between modeled predictions and actual capacity raises serious questions about the project’s justification and potential environmental impacts. The I-5 Interstate Bridge is at capacity, and can’t add more traffic All experts—and IBR—agree the I-5 bridges are at capacity at peak hours. Every analyst who has looked at the I-5 bridges has concluded that they are effectively carrying as many vehicles per hour during peak periods as is possible. Traffic count data show that PM peak hour volumes have been steady for the past twenty years. Afternoon northbound peak hour volumes have been stuck at less than 5,000 vehicles per hour since 2000. The project’s Environmental Impact Statement concedes that the maximum hourly capacity of the I-5 bridges is no more than 1,850 v/l/h or about 4,550 vehicles per hour (IBR Traffic Technical Report, Appendix A, Transportation Methods Report.). IBR forecast officials explain that traffic levels on I-5 have grown more slowly than on I-205, “due to capacity constraints and extensive congestion over the Interstate [I-5] Bridge.” CDM Smith, the national traffic expert hired by ODOT and WSDOT in 2013 to forecast traffic concluded, “Traffic under the existing toll-free operating condition on the I-5 bridge reached nominal capacity several years ago, . . . The I-5 bridge has little or no room for additional growth in most peak periods.” In spite of the universal agreement that the current bridges are at peak capacity during rush hours, Metro’s model claims that peak hour volumes will continue to increase even if nothing is built. Let’s focus on the afternoon rush hour—northbound traffic from Portland to Vancouver, between 4 and 6 pm—the period of maximum daily traffic congestion. State traffic count data show that about 4,800 vehicles crossed the I-5 bridges in the afternoon peak hour Northbound each day in 2019. But Metro’s traffic model, Kate, which is the basis for IBR’s justification, and environmental analysis makes a false claim that more than 6,000 vehicles crossed the I-5 bridges northbound in the PM peak hour. Projected peak hour exceed physical capacity The Metro model, which forms the basis of IBR’s planning, consistently predicts peak traffic levels on the I-5 bridge that exceed its demonstrated physical capacity of the bridge. 1. Current Capacity: The I-5 bridge can carry approximately 5,000 vehicles northbound in the PM peak hour, as evidenced by traffic count data. Here is a typical chart from IBR. Maximum northbound traffic flows at 5pm were 4,810 vehicles. 2. Model Overestimation: Metro’s “Kate” model claims current traffic is currently (2019) over 6,290 vehicles per hour and predicts this will increase slightly to 6,375 by 2045. Here is a screenshot of an Metro Excel spreadsheet summarizing the peak hour volumes for I-5 in 2019. Northbound volumes for single occupancy cars, multiple occupancy cars, and medium and heavy trucks are highlighted and total 6,290 vehicles in the PM peak hour in 2019: Metro spreadsheet obtained by public records request. Highlighting not in original. PM peak hour volume of 6,290 is the sum of 4,964 single occupancy cars, 1,011 multiple occupant cars, 240 heavy trucks and 76 medium trucks. 3. IBR’s Inflated Growth Estimates: Consultants for the Interstate Bridge Replacement project altered the estimated traffic levels from Metro “Kate” model, something they call “post-processing.” They recognized that Metro’s Kate model over-estimated current (2019) NB peak hour traffic levels–which they lowered to 5,740 vehicles from Kate’s 6,290. The 5,740 figure still greatly exceeds actual traffic counts. But while Metro’s Kate model allowed almost no growth in peak traffic in the No-Build through 2045, IBR’s “post-processing” allowed growth in the No-Build to increase to 6,905 vehicles per hour–more than 2,000 vehicles per hour beyond the actual physical capacity of the bridge. IBR traffic modeling presentation, obtained by public records request (detail). March 30, 2022, Slide Number 21. In sum: the IBR’s claims about peak hour traffic don’t mesh with actual data from traffic counts. The Metro Kate Model and IBR “post-processed” data over-state current traffic levels significantly. Both models assume that peak hour traffic will grow further in excess of capacity, and IBR’s “post-processing” while partly correcting for base year over-estimates, has an even higher predicted growth rate. These projections are not just optimistic; they are physically impossible given the current infrastructure. As traffic expert Norm Marshall says, models like these that fail to recognize capacity limits are “Forecasting the Impossible.” He explains Static Traffic Assignment modeling technique used by Metro and IBR . . . allows modeled traffic volumes to exceed capacity. This misrepresents traffic not only on the over-capacity segment, but on downstream segments that the excess traffic could not really reach because it either would divert to other routes or be queued upstream. Marshall, N. “Forecasting the impossible: The status quo of estimating traffic flows with static traffic assignment and the future of dynamic traffic assignment,” Research in Transportation Business and Management, https://doi.org/10.1016/j.rtbm.2018.06.002 Violating Federal Highway Administration guidance Transportation experts have long known that failing to realistically account for capacity limits leads traffic models to grossly over-estimate traffic growth. The Governmental Accountability Office and the National Academy of Sciences have both criticized this limitation of the traffic models of the type used by Metro and IBR. The Federal Highway Administration (FHWA) explicitly requires that demand estimates realistically account for capacity limitations. “Constraining demand to capacity. . . care must be taken to ensure that forecasts
are a reasonable estimate of the actual amount of 
traffic that can arrive within the analytical period . . .

Regional model forecast are usually not well constrained to system capacity” IBR clearly hasn’t taken care to assure its forecasts predict only as much traffic as the roadway can handle. The current modeling approach violated FHWA guidance, raising questions about the validity of the entire planning process. Implications of overestimated peak hour traffic Correctly estimating future peak hour traffic levels are the critical planning parameter for this project. The consequences of IBR’s inflated peak hour traffic projections are far-reaching: 1. Unjustified Expansion: By predicting traffic levels that exceed capacity, the model artificially creates congestion scenarios used to justify expanding freeway capacity. 2. A Distorted Environmental Assessment: Overstating traffic in the “no-build” scenario leads to an underestimation of the environmental impacts of the “build” option, potentially violating NEPA requirements. By exaggerating traffic and congestion in the “no-build” scenario, the IBR understates the true enviornmental effects of the build scenario. 3. Ignoring Historical Trends: The models disregard the fact that peak hour I-5 bridge traffic has not increased since 2005 due to existing capacity constraints, a point acknowledged by IBR itself. IBR uses the euphemism “demand volumes” to hide its predictions that traffic will exceed capacity IBR uses the term “demand volumes” to describe traffic levels that exceed physical capacity. This is a euphemism to conceal the fact that these are not predictions of actual levels of travel, but are modeled predictions of the number of vehicles that might use the bridge if there were no capacity constraints. The Metro RTDM model allows predicted traffic levels to exceed highway capacity. The SDEIS repeatedly uses the term “demand volumes” in its Purpose and Need Statement (two instances) and in its Traffic Analysis (four instances). This terminology allows for projections that exceed physical capacity, but it’s a concept at odds with reality. In practice, traffic demand is always constrained by available capacity. False models are no basis for multi-billion dollar decisons The IBR project’s reliance on traffic projections that exceed physical capacity undermines its credibility and raises serious questions about its necessity and environmental impact. As stewards of public resources and our environment, we must demand planning based on reality, not inflated projections. It is imperative that the IBR team address these discrepancies and provide a clear, factual basis for their projections. Without this, we risk allocating billions of dollars to a project that solves imaginary problems while potentially creating real environmental and fiscal issues. The future of our regional transportation system and the responsible use of public funds depend on a honest, data-driven approach to infrastructure planning. It’s time for the IBR project to align its projections with reality and provide the transparent, accurate analysis that the public deserves.

Exaggerated Benefits, Omitted Costs: The Interstate Bridge Boondoggle By Joe Cortright 14.12.2023 A $7.5 billion highway boondoggle doesn’t meet the basic test of cost-effectiveness The Interstate Bridge Project is a value-destroying proposition: it costs more to build than it provides in economic benefits Federal law requires that highway projects be demonstrated to be “cost-effective” in order to qualify for funding. The US Department of Transportation requires applicants to submit a “benefit-cost” analysis, that shows that the economic benefits of a project exceed its costs. We take a close, critical look at the benefit-cost analysis prepared for the proposed $7.5 billion Interstate Bridge Replacement project between Portland and Vancouver. City Observatory’s analysis of the Interstate Bridge Replacement Benefit-Cost Analysis (IBR BCA) shows that it is riddled with errors and unsubstantiated claims and systematically overstates potential benefits and understates actual costs. . It dramatically understates the actual cost of the project, both by mis-stating initial capital costs, and by entirely omitting operation and maintenance and periodic capital costs. The construction period is under-estimated, which likely understates capital costs, and overstates benefits In addition, the study also omits the toll charges paid by road users from its definition of project costs, in clear violation of federal benefit-cost guidelines. In addition, the IBR BCA study dramatically inflates estimated benefits. It uses an incorrect occupancy estimate to inflate the number of travelers benefiting from the project. The IBR BCA analysis also presents inflated estimates of safety benefits, based an incomplete and un-documented crash analysis. In addition, ODOT’s study fails to separately present the benefits and costs of the project’s tolling and capacity expansion components, and omits an analysis of the distribution of benefits and costs among different demographic groups. A correct evaluation of this project shows that its costs exceed its benefits by a wide margin. What this means is that the proposed freeway widening is not cost-effective; not only is it not something that qualifies for federal funding, it also is a demonstrably wasteful, value-destroying expenditure of public funds. The amount of money that the federal government, the States of Oregon and Washington, and highway users would pay in tolls, exceeds by a factor of more than two the actual economic benefits that would accrue to a subset of highway users. This is a project that would make us worse off economically—exactly the kind of project that the cost-effectiveness standard is established to prevent. Benefits are overstated ODOT and WSDOT claim that the present value of benefits from the IBR project amount to more than $4 billion; nearly all of these benefits are attributed to travel time savings, congestion cost reductions and seismic resilience, and reduced crash losses. ODOT’s estimates of both travel related savings and crash reductions lack documentation. Travel Benefits: The IBR BCA claims that the project will produce $2.4 billion in travel time benefits. ODOT’s estimates are plagued with errors and a lack of documentation Travel benefits are minuscule to individual travelers—averaging about 20 seconds in a typical five-mile trip, according to the BCA. These savings are imperceptible to individual travelers and are likely to be of no significant economic value. The estimates use the wrong value for peak hour vehicle occupancy, exaggerating peak travelers by 13 percent. The BCA assumes 1.67 passengers per vehicle while USDOT guidelines prescribe a figure of 1.48 passengers per vehicle. The project fails to document the diversion of traffic to the parallel I-205 bridge as a result of charging tolls on I-5; this will cause longer trips for 33,000 diverted vehicles per day, and will increase congestion and travel times for the 220,000 persons crossing the I-205 bridge. These costs will largely offset the travel time savings purported to accrue to travelers in the project area. The Benefit Cost Analysis concedes that tolling the I-5 bridges will divert traffic to the I-205 bridge, but the project’s benefit cost analysis only models the effect of the project in the study area. The added cost, pollution and other effects on the I-205 area are not included in the benefit cost analysis. The Benefit Cost Analysis admits: The Build scenario assumes tolling for the highway river crossing. The added cost from inclusion of tolls causes a reduction in I-5 auto trips as people shift to transit, use the alternative I-205 crossing, or change their destination to avoid the crossing As described, this benefit-cost analysis is highly selective: it counts beneficial time savings in the project’s “study area” but ignores the costs in added travel distances, travel times and congestion that will occur outside the study area when traffic diverts to avoid tolls. Resiliency Benefits: The IBR BCA claims savings for lives lost in a potential earthquake, savings on the cost of a replacement bridge, and added savings in traveler delay in the event that the bridges collapse in an earthquake. All these estimates are exaggerated, including probability of a major seismic event, likelihood of collapse, fatality rate in the event of a seismic event, number of persons on the bridge at the time of an event, the cost of replacing the bridge, and the scale of added travel that would result from traffic disruption if the bridge collapses. Safety Benefits: The IBR BCA claims that the project will reduce crashes on I-5 and will produce benefits with a present value of approximately $53 million. The IBR-BCA asserts that it has used the ISATe model to predict a 17 percent decline in crashes in the project area. Also, it has not documented what features of the project produce the supposed ISATe benefits, and it has failed to calibrate the ISATe model for I-5, and the ISATe methodology can’t be used to accurately compute crash reduction on highways with ramp-metering, which I-5 has. Costs are understated The IBR BCA claim that the present value of the initial capital costs of this project are $2.7 billion. That is a significant understatement. The project’s construction cost, according to other IBR BCA documents is as much as $7.5 billion. IBR BCA’s failure to comprehensively account for project costs violates federal benefit cost guidance which requires that costs include “the full cost of the project. . . regardless of who bears the burden . . including state local and private partners . . ” This should include tolls paid by users. Costs Exceed Benefits by a Wide Margin After we correct IBR BCA’s study for under-counted costs, and unsubstantiated benefit claims, the project’s benefit-cost ratio falls to dramatically less than one, which is the minimum standard for meeting the statutory requirement that the project be cost-effective. Our corrected estimates show that the actual cost of the project ranges as high as $5 billion. The actual benefits of the project, are roughly $2 billion. This means that the project has a benefit-cost ratio of between 0.4 and 0.3, well below the minimum threshold of 1.0. The correct analysis shows that the I-5 Bridge Replacement project is a value-destroying endeavor: it costs users and taxpayers far more than it provides to the public in benefits. It is not cost-effective, and should not be approved by FHWA. Failing to disaggregate benefits and ignoring distributional impacts Federal regulations require that a benefit-analysis separately report the benefits and costs of independent elements of a project. This is to prevent a prospective applicant from combining an ineligible project (with costs that exceed benefits) with an eligible project (with a positive benefit-cost ratio) in order to get a larger amount of federal funds. The IBR project consists of at least two elements with independent utility: a plan to toll I-5, and the proposed widening of the highway, intersections and approaches. Nearly all of the travel time benefits associated with the project result from tolling, according to IBR BCA’s own analysis. Appraised separately, the tolling would have a far more favorable benefit-cost ratio than the highway expansion. To comply with federal requirements, IBR BCA should produce separate benefit cost estimates for each component of the project. Federal regulations strongly encourage applicants to examine the distribution of benefits and costs among different segments of the population. IBR BCA included no distributional analysis in its benefit-cost study. Nearly all of the travel time, and congestion reduction benefits accrue to peak hour travelers. Yet a majority of the the cost of tolls are likely to be paid by travelers who use the I-5 during off-peak hours; these off-peak travelers get no travel time benefits. In effect, they are made worse off: they have to pay a toll even though they get no better service than under the no-build scenario. Conflict of interest and risk of fraud The benefit-cost analysis is more than a mere formality: it is a legal requirement for the $7.5 billion project to qualify for federal aid. False representations made in the IBR BCA could represent fraud. It is concerning that the benefit-cost analysis is prepared by a private sector contractor with a direct financial interest in the construction of the IBR. The Benefit-Cost Narrative report indicates that the report was “Prepared by WSP.” Financial records obtained from the IBR project pursuant to a public records request show that WSP has current contracts to perform paid work on the Interstate Bridge Replacement Project valued at $76,282,807.03. Indeed, WSP is the single largest contractor for the project. In the event that federal funding is not forthcoming, it is unlikely that the project will proceed, and WSP will lose this lucrative source of income. WSP is not, and cannot be, an independent and objective evaluator of the benefits and costs of this project. It has a blatant conflict of interest, which is not disclosed.

Kate: Metro’s wildly inaccurate model overstates current traffic levels By Joe Cortright 14.10.2024 The case for the $7.5 billion Interstate Bridge Replacement Project is based on traffic projections from Metro’s “Kate” travel demand model. But there’s a huge problem: Kate doesn’t accurately model even current levels of traffic. The model has a high overall error factor, and importantly, consistently over-estimates traffic on the existing I-5 bridges. Metro has prepared a validation report—not published on its website—showing the Kate model assigns vastly more traffic to I-5 than actually use the bridge. The model essentially adds 20,000 non-existent cars and trucks to I-5 each day in 2019—more than 6 million vehicles annually. The Metro forecast prepared for the Columbia River Crossing showed the same problems, over-predicting traffic growth by a factor of four between 2005 and 2019. The model claimed growth would be 1.3 percent per year; the reality was 0.3 percent growth. Ironically, Oregon and Washington have paid private sector firms to develop much more accurate models of regional traffic–but they’ve excluded these more realistic models from the IBR environmental impact statement–in likely violation of the National Environmental Policy Act. An indispensable part of the sales pitch for wider highways is the seemingly precise and statistically intimidating results of computerized travel demand models. These models purport to predict, with great certainty, future traffic levels decades from now. In the hands of state highway departments, such models are routinely used to “prove” that traffic is increasing inexorably, that if nothing is done, congestion will become intolerable, and paradoxically, that wider roads won’t actually stimulate any more traffic. In reality, the models are an intimidating fiction, like the Wizard of Oz’s flaming avatar, designed to frighten and cajole. And just as in Oz, the real manipulation is being done by the man behind the curtain. The man behind the curtain is operating Metro’s “Kate” travel model. In the high-stakes game of justifying multi-billion dollar infrastructure projects, traffic forecasts are a computer-driven trump card for project proponents. Traffic modelers use complex and impenetrable computer models to generate seemingly precise estimates of future traffic levels, which they use as a cudgel to push for over-sized highways. But a close look at the models shows that they are biased and wrong, and systematically over-state traffic, not just in the future by now. Metro’s much-hyped “Kate” regional travel demand model dramatically over-estimates current levels of I-5 traffic, as well as projecting physically impossible growth in future years. The Interstate Bridge Replacement (IBR) project offers a textbook case of modeling gone awry, with potentially far-reaching consequences for taxpayers and the environment. Kate doesn’t accurate describe the present, and can’t predict the future At the heart of the IBR’s justifications lies Metro’s regional travel demand model–dubbed “Kate.” But our analysis reveals that Kate has a penchant for fiction especially when it comes to I-5 bridge traffic. Poor Calibration. The test of a model is whether it can accurately reflect reality. For transportation models, professionals talk about “calibration” whether the predictions of the model match actual real world traffic counts. Metro’s Kate Travel Demand model has a high overall error factor. We measure overall modeling error using a statistical metric called “Room Mean Squared Error”—RMSE—which tells how far off the overall model is in matching actual data. Metro’s Kate model has a RMSE of 14.5 percent, meaning that on average, the model gets current traffic levels right within only about a 15 percent margin. Keep in mind that calibration asks whether a model can accurately predict current traffic levels. Importantly, the 14.5 percent RMSE for the Metro model is much higher than for other Portland area transportation modeling efforts. Here’s a table showing the RMSE for several other models. Comparison of Travel Demand Model Validation Model (Year) Calibration Year Scope Metric Error (RMSE) Metro/Kate (2017) 2015 32 Regional Cutlines AWDT 14.5% Stantec/IBR Level 2 (2023) 2015 32 Regional Cutlines AWDT 2.5% CDM Smith/CRC IGA (2013) 2010 11 Regional Cutlines Hourly 2.5% CDM Smith/CRC IGA (2013) 2010 I5, I205 Bridges Hourly 0.8% The other models shown here, which cover the same geography as the Kate model, have RMSE error factors of less than one percent to two-and-one-half percent. That means the error factor in the Kate model is six to fifteen times larger than for these other models. Metro’s Kate model is demonstrably less accurate and less well-calibrated than other models. Yet IBR officials have chosen to rely on Kate in their environmental analysis. Overestimation: As bad as it is in predicting overall traffic levels in the region, Kate is demonstrably worse in predicting traffic on the bridges across the Columbia River. Kate consistently overestimates traffic on the I-5 bridge, by almost 20 percent. In 2019, for instance, the Kate model says there were 164,500 average weekday trips across the I-5 bridge. The reality? A much more modest 138,530, according to ODOT’s own traffic recorders. Estimates of Calendar year 2019, Average Weekday Traffic, I-5 Bridge Source Estimate Error ODOT, Traffic Count data 138,530 0 Metro, Kate Travel Demand Model 164,500 +18.7% This fact is buried in a technical report—not published on Metro’s website—which shows that the Kate model dramatically overstates the current level of traffic. This shows the model is poorly calibrated and can’t even reflect current reality—much less accurately predict the future. Exaggerated Growth Rates: Kate is the just the latest version of Metro’s traffic-inflating models. Kate’s predecessor “Ivan” predicted that if the Columbia River Crossing project (the predecessor to IBR) weren’t built (spoiler—it wasn’t) that I-5 bridge traffic would grow at a rapid 1.3% annual growth rate from 2005 to 2030. The actual growth rate from 2005 to 2019? A paltry 0.3% per year. Metro’s travel model predicts four times as much traffic growth as actually occurred: That’s not just missing the mark; it’s not even in the same ballpark. The current Kate model also wildly over-estimates future traffic growth. Millions of Phantom Cars and Trucks: The discrepancy between Kate’s predictions and reality isn’t just a statistical anomaly. It translates to over 20,000 “phantom” vehicles per day that exist only in the model’s imagination. That’s more than 6 million non-existent trips per year. A better calibrated model produced dramatically different results While IBR officials take pains to paint the “Kate” travel demand model as an objective, scientific mechanical predictor, its actually anything but. The complex system of equations that compose the model depend on settings and inputs chosen by modelers. In this respect, its not unlike an Excel spreadsheet: If you enter different numbers in one cell, you get different results elsewhere. Other modelers, starting with the same Metro Regional Travel Demand model, plugged in different parameters, and produced a vastly more accurate forecast of I-5 traffic growth. In 2013, Oregon and Washington DOTs paid modeler CDM Smith model, commissioned for an investment-grade analysis of the Columbia River Crossing, tells a different story. After recalibrating Metro’s model, CDM Smith’s predictions aligned much more closely with reality, forecasting a 0.3% annual growth rate that matches observed data. More recently, IBR hired Stantec to produce a version of the model to estimate toll revenues; it too is vastly more accurate than the Metro model. (See Table above). The big question for public officials–and ultimately the courts–is why are ODOT and WSDOT using a model with a vastly larger error factor to plan a multi-billion dollar project, instead of more accurate models Oregon and Washington have already paid for? Biased traffic projections to justify a bloated project Why does this matter? Because these inflated numbers are being used to justify a massive, expensive project. The supposed reason that $7.5 billion in wider highway lanes and rebuilt interchanges are needed is to accommodate phantom traffic that exists only in the model. More realistic traffic projections would enable a much cheaper, less environmentally devastating project. By overstating current traffic and future growth, the IBR project is: Exaggerating the need for expanded capacity Potentially overbuilding infrastructure at taxpayer expense Understating the environmental impacts of the “build” alternative by comparing it to an inflated “no-build” scenario Concealing Kate’s inaccuracies Metro and IBR staff are aware of the problems with the “Kate” model, but have largely buried information about its bias and inaccuracy in other technical documents. Metro produced a “validation” report for Kate in 2017, but does not publish this crucial document on its website. For those who want to see the report, we’ve attached a copy we obtained via public records request below. And despite these glaring issues, Metro and the IBR continue to use the poorly calibrated Kate model “for planning purposes.” It’s hard not to conclude that they prefer these higher forecasts because they justify a larger project and conceal the travel-inducing effects of expanded capacity. When questioned about these discrepancies, one can almost hear the IBR planners channeling the Great and Powerful Oz: “Pay no attention to that man behind the curtain!” But unlike in the movie, the wizard behind IBR’s curtain isn’t a harmless humbug. Instead, it’s a flawed modeling process with the potential to waste billions in taxpayer dollars and reshape our region’s transportation landscape based on fantasy rather than fact. Time for a reality check The IBR project is betting billions of taxpayer dollars on traffic forecasts that don’t stand up to scrutiny. It’s time for a reality check. We need: An independent audit of the traffic modeling proces Transparent reporting of model inputs, assumptions, and output A reevaluation of the project’s scope based on realistic traffic projections Until then, the IBR project risks building a bridge to nowhere – or more accurately, a bridge to a future that exists only in the realm of faulty models and phantom traffic. It’s time to pull back the curtain and expose this “wizard” for what it really is: a collection of flawed assumptions and inflated projections masquerading as a scientific process. Appendix: 2017 Kate Validation Report Here is a copy of Metro’s “2017 Kate v1.0 Trip-Based Demand Model Validation Report for Base Year 2015.” This report does not appear on the Metro website (oregonmetro.gov). The report is still marked “DRAFT” years later, and no “final” version has ever been released.

The Interstate Bridge Project’s Flawed Traffic Data By Joe Cortright 11.10.2024 The Interstate Bridge Replacement Project simply can’t tell the truth about current traffic levels or recent growth rates. IBR reports inflate the current level of traffic on I-5 bridges by nearly 5,000 vehicles per day IBR reports falsely claim that I-5 bridge traffic is growing twice as fast as ODOT’s own data show IBR officials have exaggerated traffic levels and traffic growth rates to try to sell an over-sized, over-priced project. It’s important to note that this is actual, recorded data, gathered by the Oregon Department of Transportation, and published on its traffic counting website. If IBR officials can’t be trusted to accurately report current and historical data, and when they instead choose to inaccurately inflate traffic counts and claim traffic is growing twice as fast as their own data show, it raises serious concerns about whether they can be trusted to accurately project future traffic levels–a process that is inherently more difficult, and critically, largely shrouded from public view. The Interstate Bridge Replacement (IBR) project, a massive $7.5 billion undertaking to replace the I-5 bridges over the Columbia River, is built on a foundation of questionable traffic projections. As we’ve seen time and again with megaprojects, errors in traffic modeling can lead to overstated needs, financial boondoggles, and understated environmental impacts. The IBR project seems to be following this well-worn path. The importance of getting traffic numbers right Traffic counts and modeling aren’t just a technical exercise—they’re the cornerstone of the entire project. Traffic levels define the need, justify the size, evaluate alternatives, and determine financing. Understanding present and future traffic levels are also crucial for assessing environmental impacts. As the Federal Highway Administration notes, “travel and land use forecasting is integral to a wide array of corridor and NEPA impact assessments and analyses.” In other words, if the traffic forecasts are wrong, the entire environmental impact assessment is compromised. Current traffic data and recent traffic growth trends need to be accurate in order to create accurate forecasts of future activity–and IBR officials have exaggerated traffic levels and traffic growth to sell their project. IBR can’t even report current traffic count data accurately One would think that counting cars on a bridge would be straightforward. Yet, the IBR project can’t seem to agree with itself—or with the highway department’s own traffic recorders—on how many vehicles cross the I-5 bridge daily. The IBR has variously claimed 142,400 or 143,400 vehicles per average weekday in 2019. Meanwhile, ODOT’s automatic traffic recorder reports 138,780 per day for the same year. That’s a discrepancy of up to 4,620 vehicles per day—not exactly a rounding error when you’re justifying a multi-billion dollar project. Average weekday traffic for each month in 2019 is shown in second column of the right-hand panel of this table, downloaded from ODOT’s own traffic reporting website. The average weekday traffic for the twelve months January through December 2019 is 138,780 vehicles per weekday. This isn’t the first time ODOT and WSDOT have played fast and loose with traffic numbers. During the Columbia River Crossing project from 2008 to 2011, they overstated 2005 traffic levels —a fact they were forced to admit in federal court. IBR exaggerates recent traffic growth Not only does the IBR technical work get recent traffic levels wrong, it also grossly overstates the rate of growth in traffic across the I-5 bridge. The study focuses on the four-years prior to the pandemic—2015 to 2019. The IBR’s “Level 2” traffic study claims traffic on the I-5 bridge increased by 1.1 percent annually between 2015 and 2019. However, ODOT’s own official data shows the actual growth rate was only 0.55%—half of what the IBR claims. This isn’t just a minor discrepancy; it’s a fundamental misrepresentation of traffic trends that could significantly impact the project’s justification and design. The inaccurate traffic count data leads the Stantec Level 2 study to overstate the recent rate of growth across the I-5 bridges. The Level 2 study claims that between 2015 and 2019, traffic increased by 1.1 percent per year. The average weekday river crossings along the I-5 and I-205 Bridges since 2015 are presented in Figure 2-6. Between 2015 and 2019, the traffic on the I-5 Interstate Bridge increased at an annual rate of approximately 1.1% . . . Stantec, Level 2 Report, page 2-9 According to the average weekday traffic data reported on the ODOT automatic data recorder website, the actual rate of increase was only half as much—0.5 percent. We examined actual data reported on ODOT’s website (https://www.oregon.gov/odot/data/pages/traffic-counting.aspx) for the Automated Traffic Recorder for the I-5 Interstate Bridge. In 2015, average weekday traffic was 135,696 vehicles per day. In 2019, average weekday traffic was 138,700 vehicles per day. This represents an annual rate of increase of 0.55 percent per year, half the rate claimed in the Stantec Report. The difference in growth rates is a crucial point that highlights potential issues with the IBR project’s traffic projections. The failure to accurately report recent traffic growth has important implications and consequences: The IBR’s claimed growth rate is twice the actual rate based on official ODOT data. This discrepancy is significant because growth rates are often used to project future traffic volumes, which in turn justify the need for and scale of transportation projects. Overestimating the growth rate leads to inflated projections of future traffic. This could result in overbuilding infrastructure, wasting public resources, and potentially creating unnecessary environmental impacts. It might also affect the financial viability of the project, as toll revenue projections are based on these inflated growth rates. This difference in growth rates is not just a minor statistical quibble. It represents a fundamental issue with how the IBR project is analyzing and presenting traffic data. If the project is consistently overestimating traffic growth, it could lead to a significantly oversized and more expensive project than what is actually needed. This highlights the need for transparent, accurate, and verifiable traffic data and projections in planning such a massive infrastructure project. With a price tag of up to $7.5 billion, the IBR would be the most expensive transportation project in the region’s history. It’s crucial that decisions about such a massive investment are based on accurate, consistent data. Yet, what we’re seeing is a pattern of inflated numbers, inconsistent baselines, and opaque methodologies. The discrepancies and inconsistencies in the IBR’s traffic modeling raise serious questions about the project’s foundation. If we can’t trust the basic traffic counts, how can we trust the complex projections built upon them?

Tell me again how our existing streets and bridges wouldn’t see massive benefit from even a fraction of the amount being proposed for this boondoggle, maybe this time it will be even remotely convincing. And since ODOT clearly has no interest in maintaining its current infrastructure, why should it be any different this time? It’s time to grow up and do the hard work of fixing what we already have.

Having a 7 billion dollar bridge that actually slows down public transit is just crazy. We want fast light rail between the Couv and Portland. Europe does it. Why can't we?

I procured my degree in transportation planning from the University of Oregon. It is a well know FACT among planners that adding interstate lanes DOES NOT reduce traffic but rather increases traffic, this is referred to as Induced Demand. Induced Demand will lead to more traffic and congestion for all commuters. I DO NOT SUPPORT THE EXPANSION OF I-5!

More highways will lead to more driving which will lead to more congestion, pollution, climate change, and traffic fatalities. What if we spent this money on helping give people options that don't involve moving two tons of metal and glass at 60 mph?

The scale of this project is much too large and too focused on making driving easier. We know making driving more convenient will lead to more driving which will lead to more emissions. Rather we should right size this project, focus on making transit more efficient and spend our transportation dollars elsewhere that will reduce emissions. Oregon and Washington are supposed to be climate leaders and this is not a project that represents that. Thank you for your time.

Please do not build the proposed i5 highway expansion. More lanes for cars is not the direction we need to head in. The proposed project is too expensive, it harms minoritized neighborhoods, and it’s bad for the environment. We need to invest in other areas of infrastructure and reconsider the harms we are causing to neighborhoods like the rose quarter.

Many important considerations, but the most urgent and important is avoiding the huge contribution to greenhouse gasses that this would induce. This is a $7B investment in car culture and fossil fuel dependency. Imagine what $7B could do if invested in a low carbon transportation system.

I feel like we should be smarter than this as a state. It’s well documented that adding lanes doesn’t do anything to reduce traffic. Please spend money on anything, literally anything else, that will help residents of Portland

Expanding i5 is NOT the solution to resolving the tortuous traffic that plagues many hundreds of thousands of lives everyday. Smarter, more efficient, and more equitable transportation options must be seriously considered before jumping in and leveling historic neighborhoods and negatively impacting these sensitive hyper local economies. $7B put towards a light- or high-speed rail transit option, a BRT, or investment in more pedestrian-friendly modes would benefit the area more than widening the freeway. This project would be tax-payer money being thrown into thousands of gas tanks, just to be burned off for nothing other than adding to congestion and carbon emissions.

Adding another auxiliary lane won’t reduce emissions or greenhouse gases, because it ultimately encourages drivers to use personal vehicles instead of seeking public transportation. Given the short distance between the two cities, a commute from Vancouver to Portland would be easy by bike or walking. However, the expansion continues to ignore those who are truly reducing emissions by simply not creating any.

I own a car but I recognize that driving a car is not always the best mode of transport. I try to only drive when truly necessary and bike, walk, or take transit as often as I can. And many people cannot or have no desire to drive a car. With that in mind, please make the new crossing a multi-modal one. It should have wide separated multi-use paths for bikes, pedestrians, and other non-car rolling transport like scooters and wheelchairs. I would also be thrilled to see rails for trains, bus only lanes, and/or HOV/ETL lanes. Further, to make crossing the bridge a pleasant experience for those not in cars, I encourage developing a bridge design that separates out the noisy, polluting car lanes from the multi-use path via walls, extra space, or other such treatments. Making this bridge car-only or even “just” unfairly car-focused, eg via expanding the number of car lanes, is locking us in to years of higher maintenance costs, more pollution, and more induced demand for car travel, which is the last thing we need right now as we attempt to transition to sustainable transport methods and avoid catastrophic amounts of climate change.

Hi, I cannot believe the proposed plans for freeway development at Jantzen Beach. They are horrendous and the cost is exorbitant. Taxpayers should not waste $7 billion on a project that will expand freeways in that area. We do not want to become Houston or Dallas. We should greatly simplify the project and reduce the cost. What a boondoggle the state DOT has proposed. Just make a cheap bridge replacement; we do not need to pump money into freeway expansion.

Climate change is here and we are suffering the consequences now. It is absurd that in the context of wildfires, poor air quality, and housing unaffordability in Oregon we are considering spending billions on more lanes for cars. This project needs to be transit first and have less impact on the surrounding areas. We can’t continue to fund car-centric projects like this. It is literally killing us.

There is no reason to expand the highway like this. Use the money to fund buses or light rail and better bike infrastructure. This will just increase traffic and make things worse in addition to the human impact.

Expanding this highway to this degree instead of prioritizing rail, biking and bus rapid transit will only induce car demand and perpetuate congestion, affect surrounding flora/fauna, and contribute to environmental and noise pollution. We don't need this and could use this money for better projects in the setting of an alarming climate crisis.

I am a bus rider and a climate activist. I do not own a car. I want a seismically safe bridge that makes riding the bus to Washington easier and safer. A new bridge should NOT slow down my bus ride. How are we going to get more people to take transit if the new bridge makes the bus ride longer? Please build a bridge that makes mass transit more efficient, but is not a huge, expensive monstrosity ($7 billion is too much!). We need a right-sized bridge. The only way to reduce the environmental impact of driving is to have CONGESTION PRICING, so that people are incentivized to take mass transit. Building more lanes means more cars, more exhaust and more climate change. Keep our air clean! Build a smaller bridge. Build a bridge for buses and trains. Improve mass transit!

At a time of climate crisis, when our infrastructure is aging and needing repair across the region, when we need more than anything to reduce driving in favor of other transportation modalities, what in the world drives Oregon and Washington's Departments of Transportation to want to throw billions of dollars at highway widening boondoggles? The proposed replacement bridge is not just a waste of money but a completely wrongheaded project that makes me question everything about the leadership at these agencies. It is a twentieth century solution to a twenty-first century situation, and absolutely inappropriate to our moment. Go back to the drawing board and figure out a responsible solution, because what you are proposing is completely irresponsible and innappropriate in terms of ecology, in terms of tax dollars, and in terms of what transportation it will encourage. Shame on you.

Any expansion of our roads in Oregon is irresponsible. The greatest threat, by far, to our future is climate change and its related problems.. We need to drive less, much less, no matter what. Put the money the expansions would cost into alternative modes of transportation. Please, please take my plea seriously. You must have children and grandchildren too or at least have some concern about the world we are leaving future generations. Sincerely and hopefully, Sarah Deumling

Compared to the No-Build Alternative, the Modified LPA is expected to benefit transportation in 2045 by:​ Reducing crashes​ Increasing people moving through the corridor while reducing the number of vehicles on the road Improving access to public transit Providing safer and more accessible crossings for people who walk, bike and roll. Decreasing travel times and reducing the number of hours of congestion experienced at the bridge