Sunday’s Oregonian includes a front page article on the question of whether widening the Columbia River Crossing to twelve lanes will trigger land use changes that will in turn help congest the bridge again (and negatively impact air qualify).
The Oregonian has learned that traffic forecasters involved in planning a new bridge, projected to cost $4.2 billion, were told to assume a new 12-lane bridge would not trigger any more growth than if the current bridge were simply left in place. Yet a 12-lane bridge would handle 40 percent more cars during afternoon rush hour, according to the forecasters’ calculations.
Ignored is a finding by regional planners, in 2001, that eliminating the bridge’s bottleneck threatened to push job and housing growth away from other parts of the metropolitan area and concentrate them in North Portland and across the river, in a rapidly expanding Clark County.
We discussed this issue here (and some of the same documents involved) 16 months ago.
In making their designs, bridge planners had assistance from specialists with the Metro regional government. Though Metro is nationally known for using sophisticated computer tools to study sprawl and the role of highways in it, Metro’s modeling staff heeded requests by Columbia River Crossing staff to assume that all bridge solutions would have no influence on development patterns in North Portland and southwest Washington.
They did so, according to Metro’s chief traffic forecaster, to be free of the complex forces driving growth as they designed the five bridge scenarios.
“Essentially that was a simplifying assumption to assess what the difference might be between the infrastructure changes,” said Richard Walker, travel forecasting manager for Metro.
Maybe (and it’s definitely arguable) you could reasonably ignore land use changes between say 10 lanes and 12 lanes, but to not look at land use impacts between the full project and the no-build is neither realistic nor responsible!