Commentary

Highway department’s are selling multi-billion dollar highway widening projects based on flawed traffic projections. The projections prepared for the predecessor of the proposed $7.5 billion Interstate Bridge Replacement project predicted traffic would grow 1.3 percent per year after 2005.  In reality, traffic across the I-5 bridges has increased by only about 0.1 percent per year […]

What City Observatory Did This Week 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

The Interstate Bridge Project’s traffic projections pretend that the massive shift to “work-from-home” never happened The IBR traffic projections rely almost entirely on pre-Covid-pandemic data, and ignore the dramatic change in travel patterns. Traffic on  I-5 is still 7 percent below pre-pandemic levels, according to Oregon DOT data Traffic on the I-5 bridge is lower

Oregon and Washington have commissioned not just one forecast of future traffic levels on I-5 and I-205, but three different forecasts. IBR officials are clinging to the one forecast that is the least accurate, and most error-prone, and have chosen to ignore two more accurate forecasts. IBR relies on Metro’s Kate Model, which has an

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

The $7.5 billion Interstate Bridge Replacement Project’s two-decade old “Purpose and Need” statement is simply wrong, and provides an invalid basis for the project’s required Environmental Impact Statement. Contrary to claims by project proponents, the “Purpose and Need” statement isn’t chiseled in stone, rather it is required to be evolve to reflect reality and better

What City Observatory Did This Week There’s a critical flaw in the planning of the $7.5 billion Interstate Bridge project: Metro’s Kate travel demand model is wildly inflating I-5 traffic numbers. The model claims 164,050 vehicles crossed the I-5 bridges daily in 2019, but ODOT’s own traffic counters tell a drastically different story – only

How can we trust Metro’s model to predict the future, when it can’t even match the present? Metro’s Kate travel demand model, used to plan the $7.5 billion Interstate Bridge, includes 25,000 phantom cars per day in its base year estimates. The existing I-5 bridges over the Columbia River carried 138,800 vehicles on an average

To hear project officials tell it, traffic projections emerge from the immaculate and objective Metro “Kate” traffic model But in reality, IBR traffic projections are not the outputs of the Kate travel demand model.  Instead, IBR consultants have altered the Metro numbers, something the label “post-processing.” But what they’ve done, doesn’t meet the professional standards