Supporters of a new four-lane bridge over the St. Croix River are wading into stormy political waters in hopes of keeping the proposal afloat.

The National Park Service (NPS) determined in October that the St. Croix River Crossing bridge would cause "direct and adverse" harm to the scenic and recreational qualities of the river, which is protected by federal law.

"What the ruling really said was you can't put in a new bridge in a new location," Adam Josephson, east metro manager for the Minnesota Department of Transportation (MnDOT), told a gathering of 22 bridge supporters last week.

But with several years of work and planning behind them, the bridge supporters aren't giving up. They are building clout as the St. Croix Bridge Coalition to become a formal -- and formidable -- lobby in Washington, D.C.

In light of the NPS determination, the best hope for a new bridge lies with Congress, which would have to exempt the bridge from the U.S. Wild and Scenic Rivers Act. Only two exemptions to the law, which protects several free-flowing rivers nationwide from development, have been granted in 40 years, Josephson said.

Coalition members say a new bridge is critical to solving traffic congestion in Stillwater and meeting business objectives in the bustling St. Croix region. The river isn't as "pristine" as some people would believe, said Russ Korpela, who heads the Chamber of Commerce in New Richmond, Wis.

"We're not talking about putting a bridge over the Grand Canyon," Korpela told last week's gathering. "This is a fairly developed area."

Todd Clarkowski, the MnDOT engineer who has managed the St. Croix bridge project for several years, said the agency has suspended much of its work, such as right-of-way acquisition, roadway design and relocation of the historic Shoddy Mill and Warehouse buildings that lie in the path of the project. Some work will continue, such as a preliminary design of the proposed bridge, Clarkowski said.

Although MnDOT has spent $25 million to prepare for construction that was scheduled to begin in 2013, the $668 million project remains unfunded. Securing the money to build the bridge would be the coalition's other big challenge after lobbying Congress.

The supporters who gathered last week in Stillwater to forge a strategy said they didn't know whether the Republican election sweep would lead to action to exempt the bridge from laws protecting the river. U.S. Rep. Michele Bachmann introduced a bill last spring to do just that, but it hasn't advanced.

Business leaders worry about fading life span of the 1931 Stillwater Lift Bridge, which now carries about 18,000 vehicles daily over two lanes into downtown Stillwater. The city's market area has grown east into St. Croix County, Wis., with shoppers and commuters traveling both ways and businesses such as Lakeview Hospital and Anderson Windows depending on a bridge to transport customers and employees.

Commuters and tourists contribute heavily to the Stillwater and Oak Park Heights economies, said Jennifer Severson, executive director of the Greater Stillwater Chamber of Commerce and the bridge coalition's coordinator. "Changes in their travel and buying habits greatly affect the downtown Stillwater businesses," she said.

The coalition hasn't decided whether to pursue a new bridge design or embrace the current bridge proposal, Severson said. As it now stands, the proposal involves considerable approach work in Oak Park Heights, south of Stillwater, and across the river at Houlton.

The Sierra Club, which twice has filed lawsuits to stop the project, favors a much smaller bridge that doesn't dominate the scenery along the river.

Few people dispute the weakening condition of the lift bridge, which under the current new bridge plan would remain in place as part of a loop trail for walkers and cyclists.

The lift bridge is headed for another round of repairs in the fall of 2012 and could be closed to traffic while that work is done.

Kevin Giles • 651-735-3342