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.