10 reasons not to believe phony DOT claims that widening highways reduces pollution

We know that transportation is the largest source of greenhouse gas emissions in the US, and that our car dependent transportation system is the reason Americans drive so much more and consequently produce far more greenhouse gases per capita than residents of other wealthy countries.  Scientists have shown that building more and wider roads stimulates more driving, longer trips, and more decentralized land use patterns, reinforcing car dependence.

With this entire vicious cycle well-documented, it’s hard to imagine anyone arguing that a widened urban freeway would  be good for the environment, but for state DOTs and their paid apologists, it’s a frequent claim.  They’ve created trumped up projections that claim traffic and pollution will be greater if we don’t build freeways.  These are false claims, and today we take a close look at how this plays out in one egregious, if typical, project.

For years, we’ve been following the Oregon Department of Transportation’s proposed I-5 Rose Quarter freeway widening project.  The project would widen a mile-and-half long stretch of Interstate 5 in downtown Portland at that has recently ballooned to $1.2 billion.

A key part of the agency’s argument is that this freeway widening project—exactly unlike every other one that has ever been undertaken—will have essentially no impact on air pollution or greenhouse gases.  They make the fanciful claim in their Environmental Assessment that the not widening the freeway (the “no-build” option) will somehow produce more pollution than the eight- or ten-lane freeway their plans shown they’re really intending to build.  In this commentary we sketch ODOT’s claims, and present a 10-point rebuttal.

A long list of false environmental claims from Oregon DOT

Recently, a Portlander interested in the project contacted us, asking us to comment on ODOT’s Environmental Assessment, which makes these claims:

  • Traffic operations would improve on I-5 in both the AM and PM time periods, . . .
  •  Conditions for pedestrians and bicyclists would improve from increased travel route options, improved ramp terminal intersections, physical separation from motorized users, and reduced complexity of intersections.
  • Overall, the Regional Travel Demand Model results did not indicate trip increases on I-5 much beyond the Project limits (i.e., no induced demand). The 5 to 14 percent trip increase on I-5 within the Project Area is expected for an auxiliary lane project intended to improve flow between entrance ramps and exit ramps and is indicative of primarily local through-traffic.
  • While consideration of greenhouse gas emissions and the effects of climate change has not been a NEPA requirement for EAs and EISs since the Council on Environmental Quality (CEQ) withdrew its previous guidance on April 5, 2017, ODOT included an analysis of climate change in the Project EA due to the high level of agency and stakeholder interest in these issues. As reported in Section 3.5 of the EA, the 2045 operational greenhouse gas emission total for the Build Alternative is projected to decrease by approximately 22 percent compared to the 2017 emission total due to federal, state, and local efforts to develop more stringent fuel economy standards and vehicle inspection and maintenance programs and the transition to cleaner low carbon fuels for motor vehicles. These trends are expected to continue over the life of the Build Alternative. The Build Alternative would contribute to this reduction due to higher speeds, less stop-and-go traffic, and less idling on I-5. Therefore, no mitigation is proposed.

Ten reasons not to believe Oregon DOT’s false claims

There is so much that is false and misleading about these claims about traffic, air pollution and greenhouse gases that it’s difficult to know where to begin.  We’ve written about all these phony claims at City Observatory.  Here are ten reasons why everyone should ignore ODOT’s environmental analysis of this project.

1. Traffic projections assume that a five-mile long, 12-lane wide freeway was built just north of this project in 2015.  Hidden in the Rose Quarter’s traffic forecasting is an assumption that a massive, multi-billion dollar Columbia River Crossing was built as part of the “no-build”–and finished five years ago. The project is still in limbo in 2021.  This inflates traffic and increases congestion in the Rose Quarter in the “no-build,” and makes the “build” look better than it is.

2. ODOT concealed plans that show it is widening the I-5 roadway enough to accomodate 8 or 10 lanes of traffic.  Two years after ODOT published the environmental assessment we uncovered true plans for a 160-foot roadway. But its traffic modeling assumes that the freeway is expanded only from four to six lanes.   Modeling an 8-  or 10-lane road would show much more traffic and pollution.

Secret ODOT documents showed plans for 160 foot roadway, enough for a 10-lane freeway.

3. ODOT’s Rose Quarter Forecasts forecasts are completely inconsistent with the forecasts they prepared for the CRC and as part of ODOT’s own road pricing work.  Those forecasts show much lower traffic on I-5 in the RQ in the “no build” scenario.  By inflating the base case, and ignoring induced demand, the Rose Quarter forecasts cook the GHG and pollution estimates and hide the negative impacts of the project.  (For details, see the section labeled “Two sets of books”, at the end of this commentary).

4. ODOT frequently claims that “pollution will be lower in the future”—but this is entirely due to assumptions about a cleaner vehicle fleet (more electric vehicles, tougher mileage standards for remaining internal combustion cars).

“. . . operational greenhouse gas emission total for the Build Alternative is projected to decrease by approximately 22 percent compared to the 2017 emission total .  . .”

This is a classic red herring:  You get these emission reductions whether you build this project or not. It’s simply irrelevant to deciding which options to choose. And, for what it’s worth, neither electric vehicle adoption or higher fuel economy standards accomplishing as much as ODOT hoped; in fact greenhouse gas emissions from driving are up in Portland by 1,000 pounds per person

5. In response to these criticisms, ODOT routinely claims that its air quality analysis was validated by a  “peer review panel”.  The panel was a whitewash:  it wasn’t provided with any of the critiques of traffic models and air quality analysis, held no public meetings, and explicitly chose to ignore road pricing, which they admitted could greatly affect project outcomes.  Former ODOT Director Grace Crunican, who ran the review, testified that the group didn’t look at the traffic projections to see if they were reasonable or accurate, they just took them at face value. The phony traffic numbers generate phony air quality estimates.

6. There is a strong scientific consensus on induced demand, with multiple studies in the US, Europe and Japan.  Wider roads means more travel.  ODOT and other highway agencies simply ignore the science.

When pressed, professional staff ODOT and PBOT admitthis project will do nothing to reduce daily “recurring” congestion at the Rose Quarter—invalidating claims that it will produce less idling.

7. At City Observatory, we’ve developed a version of the induced travel calculator created by the University of California Davis to estimate greenhouse gas emissions from the Rose Quarter project.  Its verdict:  Widening the roadway will increase emissions by adding 17.4 to 34.8 million miles of vehicle travel and 7.8 to 15.5 thousand tons of greenhouse gases per year.

8. Highway engineers love to pretend that greenhouse gases are caused primarily by cars having to idle in traffic, and they we can fight global warming by getting cars moving faster. That’s a myth:  Improving traffic flow generates more total miles of travel which overwhelms any savings from less idling.  Also:  Cars generate more GHG per mile at speeds over 50 MPH than below (something ODOT never mentions).  Wider, faster freeways mean both more vehicle miles traveled and more greenhouse gases generated per mile traveled.  This is validated scientifically by a paper published by two scholars at Portland State University.

9. Like most state DOT’s Oregon DOT uses an outdated and flawed traffic modeling approach that fails to accurately incorporate the effects of induced demand.  These static, four-step models consistently over-estimate traffic levels and congestion for no-build scenarios, and under-estimate or completely ignored the added travel induced by creating more capacity.

10. Globally, the only strategy that’s convincingly been shown to lower congestion is road pricing, which the Oregon Legislature approved for this stretch of I-5 in 2017.  Oregon DOT failed to examine road pricing as an alternative in its 2019 Environmental Assessment.  ODOT’s own consultants say pricing I-5 would obviate any need to add lanes at the Rose Quarter.

Governor Brown ordered ODOT to look at road pricing as part of its environmental review of the project in late 2019; but the agency has simply ignored her instruction.

ODOT is keeping two separate sets of books for its I-5 traffic estimates.

There’s no question that the traffic estimates created to sell the Rose Quarter project were rigged to make the “No Build” look worse.  At the same time it generated the Rose Quarter forecasts, ODOT hired another firm to estimate future traffic on this same stretch of roadway in 2027.  It came up with dramatically lower levels of I-5 traffic in the “no-build” world.

In May 2018, at the same time it was preparing I-5 forecasts for the Rose Quarter project, ODOT also contracted for modeling of I-5 traffic for the legislatively adopted congestion pricing plan. These are contained in a report from ODOT: https://www.oregon.gov/ODOT/Value%20Pricing%20PAC/VP_TM3-Final-InitialConceptEvaluatio n.pdf

These data include baseline estimates of traffic on Interstate 5 in the Portland metropolitan area for the year 2027. The study has baseline estimates, that project future traffic conditions in the absence of congestion pricing. This study uses an I-5 cordon line North of the project area corresponds to N. Skidmore Street, which is just two blocks from the I-5 cordon line used for the Rose Quarter projections. The following table compares the projected 2027 volumes in the congestion pricing study at this cordon line with the VISUM Rose Quarter 2015 volumes. This shows that the volumes used in the VISUM model for 2015 are 21 to 37 percent higher than the expected volumes in 2027, according to the congestion pricing baseline model.

I-5 North Volumes from two ODOT models
Northbound Southbound Total Difference
Time Period RQ VISUM Model (2015)
AM Peak 8AM-9AM 4,370 4,631 9,001 37%
PM Peak 5PM-6PM 4,424 4,855 9,279 21%
Conges on Pricing Study (2027)
AM Peak 8AM-9AM 3,255 3,337 6,592
PM Peak 5PM-6PM 3,803 3,860 7,663
RQ VISUM Model, “Mainline North of Going, 2015 No Build”
Conges on Pricing Study, “Interstate Br.-Skidmore” Baseline Traffic Performance

This analysis suggests that the traffic numbers, particularly north of the Rose Quarter project area are much higher than would be expected in another arguably reasonable forecast of traffic conditions. Given the expectation of growing traffic levels in the ODOT Rose Quarter modelling, one would expect that 2027 I-5 traffic levels would be considerably higher, not lower than 2015 levels. The fact that two models, prepared for the same agency, in the same month, produce two such different pictures of traffic levels suggests that the model results are highly sensitive to the assumptions and input values used by the modelers. These key values and assumptions have generally not been provided to the public for review, making it impossible for independent, third parties to understand, replicate, and analyze the summary results presented in the Environmental Assessment.