Work begins Monday on a big pipe that will someday transport clean water from Oak Harbor’s new sewage treatment plant to the harbor.

The work on the 30-inch outfall will occur at the end of City Beach Street in Windjammer Park, but city staff members said they planned ahead so that it will have as little impact on the public as possible.

City Engineer Joe Stowell explained that the construction area will be minimized after the 50-foot lengths of high density polyethylene are welded together. The waterfront walkway has been routed around the site.

In addition, Public Works Director Cathy Rosen emphasized that the work won’t have an impact on the Fourth of July, Race Week or the hydroplane races. A barge that the contractors will use in the construction will be hidden away in the marina during the events.

The project was discussed as part of the sewage treatment plant project, but it’s really a separate endeavor in some ways, Stowell said.

“It would be necessary even without the treatment plant,” he said.

The former outfall, built in the 1950s, collapsed five years ago. Since then, the treated water has been routed to an outfall in Crescent Harbor.

Stowell said the state originally wanted the city to remove the old outfall, but then it was discovered that it contains asbestos. The material is safe in the water, he said, but it would be very expensive and complicated to safely remove it.

As a result, the city got permission to leave it in place and construct the new pipe next to it.

Like the sewage treatment plant, the outfall is being constructed through a “general contractor / construction management process,” which city officials says is more efficient and transparent than the traditional design-bid-build method.

The cost is not to exceed $3.2 million.

The outfall will bring the cleaned water and 1,200 out into the harbor to a diffuses that will distribute the water as evenly as possible, Stowell said.