Water began flowing once again last week in a section of the Whitefish River that was dammed off and drained as part of the cleanup ordered by the U.S. Environmental Protection Agency.

The river went dry from the Second Street bridge upstream to near the BNSF Railway roundhouse on Sept. 3. Portable dams made of steel beams and rubberized tarps held back the water at both ends, and river flow was diverted into three 48-inch diameter plastic pipes.

Sandry Construction performed the work under direction of Kennedy/Jenks, the environmental consultants BNSF hired to oversee the river cleanup project.

The EPA ordered the cleanup after it notified BNSF in March 2009 that the company was responsible for contamination in the river under the Oil Pollution Act. The EPA wants the river cleaned up over the next few years all the way downstream to the JP Road bridge.

In Phase 1 of the cleanup last year, Granite Construction Co. built a 720-foot long coffer dam in the river below the BNSF refueling site, where as much as 110,000 gallons of diesel fuel may remain underground, perched above the river behind a 300-foot long interceptor trench.

In Phase 2, heavy equipment removed up to 18 inches of contaminated sediment from the river bottom after the river’s upper reach was drained. The river bottom was built back up to within 12 inches of the original level using round river rock.

Jennifer Chergo, an EPA spokesperson in Denver, said just about everything associated with this phase of the cleanup will be removed from the river before winter sets in — the dams, pipes, barges and chain-link fencing. All that will remain will be the flagging.

The dams and pipes will be put back to use next year to cleanup a smaller section of river about 500 feet upstream of BNSF Railway’s property line as Phase 2B. How the cleanup will proceed further downstream has not been determined, Chergo said.

Revegetation and streambank stabilization work using high-tech sod matting and fiber roll products with native plant species will take place at the Phase 1 site and around the Second Street bridge before winter sets in, Chergo said. Additional revegetation and stabilization work will take place in the spring, she said.