What looked to be a multicar pile-up has turned out to be a fender-bender for the county’s Transportation Department. Over the last six months, County Executive Ron Sims’ staff at DOT has been under siege due to a wave of allegations that its traffic forecasting methods, which are used to approve new housing developments, are biased in favor of developers.

The charges threatened to overturn the county’s main growth management technique and potentially even halt hundreds of already-approved housing projects. But now, the most contentious battle that the DOT faced has been settled, and the planners appear to have modified their practices sufficiently to take the heat off. With the crisis passed, the county staffers are getting back to business not-quite-as-usual. Suspicions about their methods, however, are likely to continue.

The case that was settled two weeks ago, after a yearlong battle, centered on a county-approved development on the Sammamish Plateau called the Greens at Beaver Crest. In appealing that project, Plateau resident Scott Hamilton, with the help of transportation expert Joe Savage, uncovered a rash of irregularities in the county’s computer model for predicting traffic, all of which served to underestimate the potential impact of the Greens. In a ruling last October, county Hearing Examiner Stafford Smith determined that the county’s system for evaluating “traffic concurrency” was “arbitrary and capricious,” and he called for changes.

Since then, the DOT has gone back and reworked its computer model, following some of Smith’s directives. “We believe the work we’ve done totally satisfies” the examiner’s concerns, says Bill Hoffman, the county’s chief of transportation planning. He adds that the numbers the new model has generated are “not that much different” from the old one.

Hearing Examiner Smith also seems to have withdrawn one of the most significant objections he had made, which had to do with the county’s practice of measuring traffic impacts from a project in only one direction, then comparing that number to total traffic moving both ways. The DOT stopped using that method a year and a half ago at the request of Sims—though long after the Greens and hundreds of other homes were approved.

Smith is apparently satisfied with the current procedure. And Hamilton is no longer going to press the issue: He has agreed to drop his appeal in exchange for the developers scaling down their project. “We got about 90 percent of what we wanted,” says Hamilton. “We sought to prove the [county’s] concurrency system was flawed and we did. This is the first appeal that actually changed the way the county does business.”