Portland’s adopted Regional Transportation Plan commits the Metro area to reduce total vehicle miles traveled by 12 percent over the next twenty-five years.
But the traffic forecasts used to justify the $7.5 billion Interstate Bridge Replacement (IBR) Project call for more than a 25 percent increase in driving over that same time period
The RTP is required under state law to plan for a reduction in VMT per capita; the RTP is the way that regional and local governments show they comply with these state climate requirements
But the IBR planning is predicated on a world where we drive much more and not any less.
Projects like the IBR are required by state and federal law to be consistent with the adopted Regional Transportation Plan, but they are being planned for traffic levels that flatly violate that plan and state requirements.
The Interstate Bridge Replacement project’s traffic forecasts are on a collision course with reality – and with legally binding climate commitments. While the Portland region has adopted ambitious goals to reduce driving and greenhouse gas emissions, IBR’s plans assume we’ll do exactly the opposite, projecting a massive 26-27 percent increase in vehicle miles traveled (VMT). This disconnect isn’t just poor planning – it may violate federal law.
State law and Metro’s RTP commit the region to reducing total driving by 12 percent
Let’s start with the legal requirements. Metro, Portland’s regional government, has adopted a Climate Smart Strategy calling for a 75 percent reduction in greenhouse gases. The state’s Climate Friendly and Equitable Communities (CFEC) rules require Metro to reduce per capita vehicle miles traveled by 35 percent between 2005 and 2050. These aren’t aspirational goals – they’re legal requirements incorporated into Metro’s federally mandated Regional Transportation Plan (RTP), adopted in November 2023.
Under state land use regulations, Metro is required to adopt a Regional Transportation Plan (“RTP”) in which Vehicle Miles Traveled (“VMT”) declines by 30 percent from 2005 levels by 2045. The Climate Friendly and Equitable Communities Rule OAR 660-012-0160(6) provides:
Metro shall adopt a regional transportation plan in which the projected vehicle miles traveled per capita at the horizon year using the financially-constrained project list is lower than the estimated vehicle miles traveled per capita at the base year by an amount that is consistent with the metropolitan greenhouse gas reduction targets in OAR 660-044-0020. [emphasis added]
By 2045, the plan, together with advancements in fleet and technology, is expected to reduce VMT per capita of light-duty household vehicles by 39 percent (compared to 2005 levels) and by 31 percent from (compared to 2020 levels).
Metro 2023 Regional Transportation Plan, Appendix J. page 9.
The per capita reduction translates into a real reduction in total driving over the next two decades. The math is simple: to meet these targets, the region needs to hold total vehicle miles traveled at about 12 percent below current levels through 2045, even as population grows. Metro’s RTP specifically projects a 31 percent reduction in per capita VMT from 2020 levels by 2045.
IBR traffic forecasts plan for 36 percent more driving
But IBR’s traffic forecasts live in an alternate universe where these policies don’t exist. The project’s Supplemental Draft Environmental Impact Statement (SDEIS) projects that regional VMT will balloon from 43.1 million daily miles today to 58.8 million by 2045 – a 36 percent increase that assumes driving per person will remain essentially unchanged.
Here are the details: The DSEIS claims that base level of driving in the Metro area was about 43.1 million miles in 2015:
The DSEIS summarize the results of its modeling to show that the region will drive about 58.8 million miles in 2045.
This represents annual VMT growth of about 1 percent per year, and essentially no-per capita decline in VMT, completely at odds with adopted regional policy. Traffic forecasts for the area in and near the IBR project tell the same story. IBR projects VMT in the “study area” will jump from 11.7 million daily miles to 14.2-14.3 million – an increase of roughly 22 percent. This growth directly contradicts Metro’s RTP, which calls for reducing total regional VMT about 12 percent in order to achieve the mandated reduction in VMT per capita of more than 30 percent.
The SDEIS Leaves out Oregon climate regulations
Perhaps most telling is what’s missing from IBR’s climate analysis. While the SDEIS includes a lengthy inventory of state climate policies, it completely ignores Oregon’s Climate Friendly and Equitable Communities (CFEC) rules requiring Metro to reduce per capita VMT by 30 percent. This selective amnesia is hardly surprising – acknowledging these requirements would expose how fundamentally IBR’s traffic projections conflict with binding regional commitments to reduce VMT.
This isn’t just about numbers on a spreadsheet. By assuming away adopted climate policies, IBR creates a self-fulfilling prophecy: project a future of ever-increasing car dependence, then build massive infrastructure to accommodate it. This approach not only undermines regional climate goals but also violates the National Environmental Policy Act’s requirement that environmental analyses be based on reasonable assumptions consistent with adopted plans and policies. NEPA requires that the EIS demonstrate consistency with adopted State and local statues and plans (40 C.F.R. § 1506.2(d)). Specifically, an EIS must evaluate “[p]ossible conflicts between the proposed action and the objectives of Federal, regional, State, and local . . . land use plans, policies and controls for the area concerned.” 40 C.F.R. § 1502.16(c) (1978). “Where an inconsistency exists, the statement should describe the extent to which the agency would reconcile its proposed action with the plan or law.” 40 C.F.R. § 1506.2(d) (1978). The Draft Supplemental Environmental Impact Statement fails to identify this conflict with Oregon climate regulations and the Metro RTP, and also therefore fails to explain how it will reconcile its proposed action to these plans.
IBR officials might argue that their much higher traffic projections are somehow more realistic forecasts of future behavior. But this misses the point entirely. The region has made legally binding commitments—codified in its federally required Regional Transportation Plan—to reduce driving to achieve climate goals. The National Environmental Policy Act and federal transportation planning regulations require that projects like the IBR be consistent with this adopted policy framework, not against a hypothetical future where we abandon our climate commitments.
The solution is straightforward but would require a fundamental rethinking of the project: IBR must revise its traffic forecasts to align with adopted regional policies as required by federal and state law. This means lowering future VMT levels to about 12 percent below today’s traffic levels, not more than 25 percent higher as in the current modeling.
Until then, IBR’s traffic forecasts remain an exercise in illegal magical thinking – assuming away binding climate commitments to justify a massive highway expansion. It’s an approach that not only fails to meet legal requirements but also locks the region into precisely the car-dependent future we’ve committed to avoiding.
The choice is clear: either revise the project to align with regional climate commitments, or admit that IBR represents an abandonment of those goals. What we cannot do is continue pretending that we can meet our climate targets while building infrastructure designed for ever-increasing levels of driving.
IBR contradicts region’s climate commitments
IBR Traffic Forecasts Violate Portland Region’s Climate Commitments
Portland’s adopted Regional Transportation Plan commits the Metro area to reduce total vehicle miles traveled by 12 percent over the next twenty-five years.
But the traffic forecasts used to justify the $7.5 billion Interstate Bridge Replacement (IBR) Project call for more than a 25 percent increase in driving over that same time period
The RTP is required under state law to plan for a reduction in VMT per capita; the RTP is the way that regional and local governments show they comply with these state climate requirements
But the IBR planning is predicated on a world where we drive much more and not any less.
Projects like the IBR are required by state and federal law to be consistent with the adopted Regional Transportation Plan, but they are being planned for traffic levels that flatly violate that plan and state requirements.
The Interstate Bridge Replacement project’s traffic forecasts are on a collision course with reality – and with legally binding climate commitments. While the Portland region has adopted ambitious goals to reduce driving and greenhouse gas emissions, IBR’s plans assume we’ll do exactly the opposite, projecting a massive 26-27 percent increase in vehicle miles traveled (VMT). This disconnect isn’t just poor planning – it may violate federal law.
State law and Metro’s RTP commit the region to reducing total driving by 12 percent
Let’s start with the legal requirements. Metro, Portland’s regional government, has adopted a Climate Smart Strategy calling for a 75 percent reduction in greenhouse gases. The state’s Climate Friendly and Equitable Communities (CFEC) rules require Metro to reduce per capita vehicle miles traveled by 35 percent between 2005 and 2050. These aren’t aspirational goals – they’re legal requirements incorporated into Metro’s federally mandated Regional Transportation Plan (RTP), adopted in November 2023.
Under state land use regulations, Metro is required to adopt a Regional Transportation Plan (“RTP”) in which Vehicle Miles Traveled (“VMT”) declines by 30 percent from 2005 levels by 2045. The Climate Friendly and Equitable Communities Rule OAR 660-012-0160(6) provides:
Metro’s adopted RTP promises to meet this goal:
The per capita reduction translates into a real reduction in total driving over the next two decades. The math is simple: to meet these targets, the region needs to hold total vehicle miles traveled at about 12 percent below current levels through 2045, even as population grows. Metro’s RTP specifically projects a 31 percent reduction in per capita VMT from 2020 levels by 2045.
IBR traffic forecasts plan for 36 percent more driving
But IBR’s traffic forecasts live in an alternate universe where these policies don’t exist. The project’s Supplemental Draft Environmental Impact Statement (SDEIS) projects that regional VMT will balloon from 43.1 million daily miles today to 58.8 million by 2045 – a 36 percent increase that assumes driving per person will remain essentially unchanged.
Here are the details: The DSEIS claims that base level of driving in the Metro area was about 43.1 million miles in 2015:
The DSEIS summarize the results of its modeling to show that the region will drive about 58.8 million miles in 2045.
This represents annual VMT growth of about 1 percent per year, and essentially no-per capita decline in VMT, completely at odds with adopted regional policy. Traffic forecasts for the area in and near the IBR project tell the same story. IBR projects VMT in the “study area” will jump from 11.7 million daily miles to 14.2-14.3 million – an increase of roughly 22 percent. This growth directly contradicts Metro’s RTP, which calls for reducing total regional VMT about 12 percent in order to achieve the mandated reduction in VMT per capita of more than 30 percent.
The SDEIS Leaves out Oregon climate regulations
Perhaps most telling is what’s missing from IBR’s climate analysis. While the SDEIS includes a lengthy inventory of state climate policies, it completely ignores Oregon’s Climate Friendly and Equitable Communities (CFEC) rules requiring Metro to reduce per capita VMT by 30 percent. This selective amnesia is hardly surprising – acknowledging these requirements would expose how fundamentally IBR’s traffic projections conflict with binding regional commitments to reduce VMT.
This isn’t just about numbers on a spreadsheet. By assuming away adopted climate policies, IBR creates a self-fulfilling prophecy: project a future of ever-increasing car dependence, then build massive infrastructure to accommodate it. This approach not only undermines regional climate goals but also violates the National Environmental Policy Act’s requirement that environmental analyses be based on reasonable assumptions consistent with adopted plans and policies. NEPA requires that the EIS demonstrate consistency with adopted State and local statues and plans (40 C.F.R. § 1506.2(d)). Specifically, an EIS must evaluate “[p]ossible conflicts between the proposed action and the objectives of Federal, regional, State, and local . . . land use plans, policies and controls for the area concerned.” 40 C.F.R. § 1502.16(c) (1978). “Where an inconsistency exists, the statement should describe the extent to which the agency would reconcile its proposed action with the plan or law.” 40 C.F.R. § 1506.2(d) (1978). The Draft Supplemental Environmental Impact Statement fails to identify this conflict with Oregon climate regulations and the Metro RTP, and also therefore fails to explain how it will reconcile its proposed action to these plans.
IBR officials might argue that their much higher traffic projections are somehow more realistic forecasts of future behavior. But this misses the point entirely. The region has made legally binding commitments—codified in its federally required Regional Transportation Plan—to reduce driving to achieve climate goals. The National Environmental Policy Act and federal transportation planning regulations require that projects like the IBR be consistent with this adopted policy framework, not against a hypothetical future where we abandon our climate commitments.
The solution is straightforward but would require a fundamental rethinking of the project: IBR must revise its traffic forecasts to align with adopted regional policies as required by federal and state law. This means lowering future VMT levels to about 12 percent below today’s traffic levels, not more than 25 percent higher as in the current modeling.
Until then, IBR’s traffic forecasts remain an exercise in illegal magical thinking – assuming away binding climate commitments to justify a massive highway expansion. It’s an approach that not only fails to meet legal requirements but also locks the region into precisely the car-dependent future we’ve committed to avoiding.
The choice is clear: either revise the project to align with regional climate commitments, or admit that IBR represents an abandonment of those goals. What we cannot do is continue pretending that we can meet our climate targets while building infrastructure designed for ever-increasing levels of driving.
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