The U.S. Forest Service has taken longer than expected to complete a draft environmental review of Bend’s $68 million Bridge Creek water supply project.

The delay will likely force the city to change its work schedule again, and that could raise the project cost, according to the city.

The Bridge Creek project already faced delays during a previous federal environmental review and when opponents sued to stop it last year. The city changed part of its plan and reapplied in December for Forest Service approval of the project, this time with a proposal to keep the current cap on the amount of water the city can take from Bridge Creek and Tumalo Creek.

The Forest Service had initially estimated that a draft of this environmental assessment would be ready for public comment at the end of February.

Instead, the earliest the draft will be available to the public is in the coming week, Deschutes National Forest spokeswoman Jean Nelson-Dean wrote in an email.

“In this circumstance, given the previous litigation, there is a desire to make sure that the analysis is fully documented and people have had the opportunity to review and make changes if necessary,” Nelson-Dean wrote.

The Forest Service has completed the draft environmental document but is waiting for officials in Washington, D.C., to determine whether the Deschutes National Forest should follow a new process to gather public input or stick with the old one.

The Bridge Creek project will replace the current water intake facility and two old pipelines — one that is roughly 90 years old and another that is approximately 60 years old — with a single new pipe.

The project also includes a new water treatment plant to remove or deactivate the parasite cryptosporidium, although that part of the project has slowed while the City Council considers whether to change the type of treatment technology.

Bridge Creek Project Manager Heidi Lansdowne said changes to the schedule will increase cost. City employees hoped to build the pipe crossing at Tumalo Creek this fall, and then install the pipeline downhill along Skyliners Road. This would mean the upper section of pipe would be in the ground before the snow falls, Lansdowne said.

“We probably won’t make the creek crossing this year with the delay in the (environmental assessment),” Lansdowne said.

Instead, the city will likely ask the contractor to first install the pipeline under Skyliners Road in order to finish that work by Deschutes County’s deadline.

The city is trying to install a section of new pipeline under Skyliners Road by 2014, when the county plans to rebuild the road in time to qualify for federal funding. If the city misses that window, it could cost as much as $2.9 million to resurface the road.

However, county Road Department Director Chris Doty has said county officials are reluctant to even discuss allowing the city to cut into a road that has yet to be built.

After the pipe is installed under the road, the city can move on to the creek crossing in late summer or fall 2014.

“Really the only time we can work in Tumalo Creek is the summer and early fall,” Lansdowne said. The Oregon Department of Fish and Wildlife sets the “work windows” when work can occur in streams, in order to minimize impacts on fish and other organisms.