Post Falls HED North Channel Dam Rehabilitation
Avista’s Post Falls Hydroelectric Development (HED) has been generating low-cost renewable energy for Avista customers for 118 years. The historic facility consists of three dam structures where the Spokane River branches into three channels nine miles downstream of Coeur d’Alene Lake.
- The Middle Channel Dam houses six generating units which produce up to 15 Megawatts of clean energy enough to power 11,250 homes.
- The North and South Channel Dams help control the water levels of Coeur d’Alene Lake and parts of the Coeur d’Alene, St. Joe and St. Maries Rivers (during summer recreation season).
- The HED also makes it possible to provide boating and swimming opportunities near Q’emiln Park.
Project Details and Timeline
In 2021, Avista assessed the condition of the North Channel Dam and identified the need for a spillway rehabilitation project. This will include rehabilitation of the dam’s concrete structure, replacement of its steel spillway gates and gate hoists, and upgrades to the electrical and control systems. To ensure the continued safe and reliable operation of this historic facility, construction will begin spring 2024 with work to be completed in spring 2027.
Visitors should expect to see the installation of a temporary access road, and a temporary retaining wall on the upstream side of the spillway gates. Work on the gates can begin once the area between the retaining wall and spillway gates has been dewatered, following spring runoff. A total of nine spillway gates, associated hoist and mechanical equipment, piers and abutments will be replaced.
Avista anticipates that Coeur d’Alene Lake water levels will not be impacted by the project. Though, as with all construction work, there will be temporary impacts due to construction.
Falls Park
Access to some areas of Falls Park will be impacted to maintain safety for the public, recreationalists, and workers. The main parking lot will be closed to the public (2024-2027) to be used as an active construction site with material, equipment, and vehicles in the area. Limited sections of the park, including the boardwalk and one of the three dam overlooks, will be closed to accommodate construction activity and maintain public safety. However, the majority of the pedestrian trails throughout the park will remain open to the public, as well as the restroom, fishing pond, and playground. Falls pond will continue to be stocked for fishing. Additionally, to enhance visitor safety, construction and directional signage will be installed at key locations throughout the park. For the safety of visitors, it is important to comply with construction signs and stay out of fenced construction areas.
Once the new spillway gates are in service, Falls Park will be restored to pre-existing or better condition.
Q’emiln Park
The boat launch at Q’emiln Park may be used intermittently and for short periods of time to launch small barges and/or load small construction platforms. The Q’emiln Park boat launch opening and closing schedule will not be impacted by the North Channel project, as the operating schedule remains dependent upon water levels and weather.