Lower Wenatchee River Flow Enhancement Project

The objective of this project is to improve habitat by increasing flows in the Lower Wenatchee by 38.27 cubic-feet per second (CFS). This project intiated and implemented the primary phase of the Pioneer Water Users Association project in the lower 7.0 miles of the Wenatchee River. This project created infrastructure improvements for the Pioneer Water Users Association (PWUA) who operate and maintain the Gunn Ditch, which supplies water for agricultural and residential irrigation to shareholders. The project has several components that will address limiting factors in the Wenatchee and is part of the Upper Columbia Salmon Recovery Board implementation schedule. By initiating this project, other biologically productive restoration activities can also be implemented, including habitat improvements, diversion removal, and possible side channel reconnection.

This project has three key elements: 1) The project will replace the PWUA current conveyance system, a gravity fed open ditch, with a new enclosed pressurized system and 2) change the PWUA point of diversion from the flow limited Wenatchee River to the confluence with the Columbia River and 3) will remove a side channel concrete diversion dam just upstream of Monitor. This project protects 38.27 cfs of the historically diverted water back into the lower 7.0 miles of the Wenatchee River, benefiting habitat for fish, particularly during low flows. The water is permanently protected as an in-stream flow right through Washington States Trust Water Rights Program (TWRP).

There are two main benefits derrived from this project that improve instream flow for ESA listed and other culturally signifigant species in the Wenatchee. The first is this project permanently protects 38.27 CFS instream from the old point of diversion(POD) upstream from Monitor WA to the confluence of the Wenatchee and Columbia rivers through the change in POD. The second is this project is operated under pressure, allowing an on demand use of the resource, so the only time water is used when it is needed, not continually like most irrigation and gravity diversions. This project should be the showcase for water use in Washington State. In addition, a 85 foot channel spanning diversion dam was removed on the Wenatchee River, creating free passage for salmonids until Dryden, Wa.