Trail Lake Project

The Columbia Basin Project serves roughly 671,000 acres of irrigated land in east central Washington. The Main Canal begins at the headworks of Dry Falls Dam, located in Coulee City at the southern end of Banks Lake, and flows approximately 1.8 miles to the Bacon Siphons. From the outlet of the Bacon Siphons, the canal conveys water for approximately one mile through an unlined canal section and then transitions to a concrete lined canal section as it flows adjacent to Trail Lake.

In the late 1970s the Trail Lake section of the Main Canal began leaking and consequently filling the Trail Lake Coulee. The lake currently continues to fill each irrigation season due to this leakage. The problem at this site is the extensive damage to the canal’s concrete lining caused by the pressure exerted on the canal by the lake. As water is drawn down in the canal at the end of irrigation season, the lake water level decreases at a slower rate. This difference in water surfaces between the lake and the canal cause the concrete panels to collapse. That damage results in continual maintenance at the Trail Lake section of the Main Canal.

Numerous reports and investigations pertaining to this continual need for maintenance have been completed throughout the Columbia Basin Project’s history. In 2014, it was further studied by staff from Reclamation’s Regional Office and Ephrata Field Office (EFO) to develop alternatives that would address the continual maintenance issues. The conclusion of the 2014 investigation led to the initial design plans of a permanent pump station that would allow the dewatering of Trail Lake and the Trail Lake section of the Main Canal.

A Trail Lake Committee (TLC) was established in early 2016 to advise Reclamation on possible solutions to this issue. The committee is working through alternatives that that would eliminate the continual maintenance issues in the Trail Lake section of the Main Canal. The TLC agreed that the main goals of the Trail Lake Project are to deliver water to the Columbia Basin Water Users in a safe and effective manner, reduce the likelihood of damage or failure to the canal system, improve reliability of the canal system and reduce the operation and maintenance costs associated with this section of the canal.

Related Documents
10-25-2016 Meeting Minutes PDF 22 kb
07-26-2016 Meeting Minutes PDF 26 kb
05-24-2016 Meeting Minutes PDF 28 kb
04-26-2016 Meeting Minutes PDF 33 kb
09/2014 Summary of Groundwater Conditions in the Trail Lake Area, Feasibility Design for Main Canal Rehabilitation PDF 3.49 mb
07/2014 Trail Lake Dewatering Alternative Conceptual Design Report PDF 4.94 mb


Sara Millard
Mechanical Engineer
Irrigation Operations & Technical Services Group
(509) 754-0232

Bureau of Reclamation
Ephrata Field Office
P.O. Box 815
Ephrata, WA 98823

Last Updated: 1/9/17