Workers place steel anchor bolts with high strength resin into the bedrock to create a solid foundation for the weirs
during our Spokane River aesthetic flows project in downtown Spokane.
Avista’s work on the aesthetic flows project in the river in downtown Spokane is getting a lot of attention from curious onlookers wondering what the project is all about. The reason behind the project isn’t just about looks as the name suggests. While the overall goal is to create a cascading waterfall effect through the channels of the Spokane River that run north and south of Canada Island, the work is related to the aesthetic spills requirement of our Federal Energy Regulatory Commission (FERC) license.
In 2009, Avista was issued a new 50-year license by FERC to operate our five hydroelectric dams on the Spokane River (Post Falls, Upper Falls, Monroe Street, Nine Mile and Long Lake). The purpose of the aesthetic flows project is to return the river’s channels to a more natural state, the way they were before early developers in Spokane cut into the bedrock to divert water during dry times.
The spray-painted dots you see on the riverbed (in the image above and to the right) are outlines for where the concrete weirs will be installed. Weirs are structures that divert water. Last year, Avista brought together several stakeholder groups, including the Washington Department of Ecology, The Sierra Club, and others, to take part in a pilot test for the project using sandbags as temporary weirs to divert the water. The feedback we received helped us determine the placement for the permanent weirs.
Our contractor is currently placing steel anchor bolts with high strength resin into the bedrock to create a solid foundation for the weirs. The weirs will be custom made to match the natural basalt bedrock as much as possible, including consideration for the existing terrain’s texture and color.
In addition to providing aesthetic attributes, the project will accommodate fish passage at various water flow levels that are determined by the Department of Fish and Wildlife and the Department of Ecology. During the project, fish biologists and contractors are on site, relocating fish safely downstream due to the river flow being temporarily stopped while the weirs are constructed.
Once the project is complete, water will flow more evenly throughout the two channels of the river and will produce a more pleasing flow of water through Riverfront Park. The project is expected to be complete by the end of October so you will most likely continue to see activity in the river channel throughout the fall.