Three months of engineering study comparing two possible routes for the Central Corridor light-rail line through the University of Minnesota are over, and the results are decisive: One route can be built sooner and will serve more people. It's on Washington Avenue, which would be converted to an auto-free transit and pedestrian mall.

The University of Minnesota's preferred route, a "northern alignment" through Dinkytown and north of the new Gopher football stadium, was held up to comparison with the Washington Avenue option last Wednesday in a four-hour meeting of the 12-member Central Corridor management committee. A vote by the panel was delayed for one week, at the request of Gov. Tim Pawlenty and University of Minnesota President Robert Bruininks. But in agreeing to the delay, a majority of committee members also indicated a strong preference for the Washington Avenue route. It's our choice, too. Here's why:

•The transit mall can be built by 2014, while the Dinkytown route would require at least one and possibly two more years to build. Each year of delay is projected to boost the project's costs $40 million, not to mention the costs associated with keeping would-be transit users stuck in traffic.

•The feasibility of the Dinkytown route remains in doubt, Central Corridor project director Mark Fuhrmann said. Its proximity to freight trains and polluted land pose problems that may prove too costly to solve.

•Ridership projections are considerably lower for the Dinkytown route -- in the range of 6,000 riders per weekday -- even if federal rules are bent to account for the presence of the university's shuttle bus system. There's no assurance that the Federal Transit Administration would permit that kind of twist in its rules. Satisfying the FTA matters because the feds are expected to pay half of the new line's $900 million cost.

•Even with the bending of the federal formulas, the Dinkytown route would not meet the cost-effectiveness test federal rules impose. A Washington Avenue transit mall does.

•A $25 million traffic mitigation plan is in the works to cushion the surrounding neighborhood from ill effects from the diversion of auto traffic under the Washington Avenue plan. A strategy has also been identified for protecting research buildings from the intrusion of unwanted electrical fields.

University officials argue that the Dinkytown route would be less disruptive to existing traffic patterns and human habits.

That's true, but that argument overlooks the possibility that moving 90 percent of vehicular traffic off of Washington Avenue might be a desirable disruption for the university. The East Bank campus likely would be safer, quieter and more attractive without bumper-to-bumper traffic chugging through its heart day and night. Central Corridor planners expect to spend $11 million on the transit mall's design -- enough to turn the stretch into what Mayor R.T. Rybak calls "a new front door for the university."

Delay in action by the corridor management team and the Metropolitan Council affords all the stakeholders more time to ponder the implications of the engineers' analyses of the two routes. Although a few more days won't change the numbers that favor Washington Avenue, they may give the creative thinkers in charge of the Central Corridor line a chance to help the university community feel more comfortable with the only real option that remains.