POST FALLS - Even with the mild winter, construction on rebuilding Avista Utilities' South Channel Dam will finish four months behind schedule.

"The project is running behind, but it is still on budget," said Debbie Simock, Avista spokeswoman, referring to the $13.5 million project next to Q'emiln Park.

"The mild winter did not necessarily help make up the time, but the delay would be longer if it hadn't been such a mild winter."

The project has been under construction for a year.

As of last fall, it was expected to be completed in March with landscaping done in April or May. However, in an update issued on Monday to Spokane River property owners, Avista said construction is now expected to be completed in July with the addition of a new viewing area, interpretive signs and landscaping expected to be completed in September.

Mary Jensen, project engineer, will provide the Post Falls City Council with an update on the project tonight at 6.

Simock said causes for the delays were an unexpected redesign of the cofferdam and the discovery of unstable rock. The construction of the cofferdam was delayed when dredging uncovered eroded rock beneath the water level on the north side of the dam.

"This required a redesign of the cofferdam and modification to permits," she said. "There was also a delay with unstable rock above the construction work area on the north side of the dam which created an unsafe situation for workers below. Anchors were installed in the rock and steel netting added to secure the area. Both will remain in place permanently."

Both delays occurred in 2014 during the early phase of the project and prior to the deconstruction work on the structure.

A milestone was reached in late January when reconstruction of the dam began with the initial pouring of concrete. After concrete work is complete, the new spillgates and controls will be installed, the cofferdam removed and the rehabilitated dam and spillway will be ready for testing and operation.

The project is being funded by rate-payers as part of Avista's capital improvement program.

The former South Channel Dam was 108 years old and one of three dams that Avista owns on the Spokane River at Post Falls. It is not used to generate power, but helps lower lake and river levels during the spring runoff season. The North Channel Dam was upgraded in 2004 and the Middle Channel Dam was upgraded in 2012.

Avista has posted a time-lapse video at avistautilities.com/postfalls on the construction of the South Channel Dam through mid-February. Click on the photo of the dam to start the video. The video will be updated again when the project is complete.