Short term water right permit allows refilling of Lake Tapps for recreational use

Photo of Lake Tapps

July 1, 2015  Lake Tapps is open for recreational use other than motorized craft after the Cascade Water Alliance (CWA) refilled much of the lake with water from the White River.  The Department of Ecology has issued a short term water right permit for refilling the lake with water that has been stored behind Mud Mountain Dam to allow repairs on a fish barrier.

The permit allows the CWA to divert water from the river for refilling the lake at the rate of 1,500 cubic foot per second through July 10th.  CWA recommends that lake users check with the City of Boney Lake, Pierce County Parks, private parks and homeowner associations about access to the lake and what activities are allowed based on water levels in each area of the reservoir.  For fishing updates, contact the Washington Department of Fish and Wildlife.

The U.S. Army Corps of Engineers (COE) stored water behind Mud Mountain Dam to repair a downstream apron on the fish barrier.  The barrier is part of COE’s system to transport endangered salmon above Mud Mountain Dam. The COE is required under federal mandate to repair the apron so as to not harm or kill fish.

Lake levels in Lake Tapps were lowered substantially this past winter to complete 16 infrastructure projects to the reservoir’s 12-mile system of flumes, pumps, valves and dikes  but the declining flows in the White River prevented refilling the lake in time for use over the Memorial Day weekend.  The mechanisms to fill the lake have been functioning as they should but drought conditions stalled the refilling.

The Lake Tapps Reservoir is normally drained every winter and refilled for summer. CWA reopened the Lake Tapps Reservoir System in March, after being down for more than seven months for significant repairs, maintenance and improvement to the 100-plus year-old system.  CWA began refilling Lake Tapps on March 13, as planned.

CWA is limited as to how much water it can withdraw from the White River. By state law, there must be certain amounts of water left in stream for fish, wildlife, recreation and the natural environment. And the White River is experiencing all-time low flows, the lowest flows of record in the past 50 years, so filling the reservoir has been substantially delayed this summer.

Background on Lake Tapps and its purchase by Cascade Water Alliance

Lake Tapps Reservoir was completed in 1911 by Puget Sound Energy (PSE) for hydroelectric power. It is now owned and operated by the Cascade Water Alliance for eventual municipal water supply.

PSE stopped hydropower operation in 2004 because of the costs of project operation associated with a Federal Energy Regulatory Commission hydropower license and sold the project to the Cascade Water Alliance in 2009.

In 2010, the Dept. of Ecology (Ecology) issued to CWA four interrelated water rights and one water right change.  The water rights package completed a multi-year project to propose and develop a regional water supply system to meet the Central Puget Sound’s long-term municipal needs.  Lake Tapps is expected to provide a drinking water supply for nearly 400,000 residents in Bellevue, Redmond, Kirkland, Issaquah, Tukwila, the Covington Water District, the Sammamish Plateau Water and Sewer District and the Skyway Water and Sewer District.

The water rights package approved by Ecology allows CWA to store water in the Lake Tapps Reservoir, divert water from the White River into Lake Tapps to supply water for the Water Supply Project, and withdraw water from Lake Tapps for municipal water supply purposes.  It is expected that the project will take 50 years to fully develop and gives CWA the authority to take an average of 48 million gallons of lake water a day (equivalent to a football field covered with water 147 feet deep) for public use.

Part of CWA’s agreement with Ecology was that Lake Tapps would remain filled for the benefit of homeowners and recreational users.  The agreement also included a sizeable trust water donation, discussed below.

The Cascade Project consists of a diversion dam on the White River at the town of Buckley, an 8-mile flow line, an off channel storage reservoir (Lake Tapps) and a powerhouse and tailrace canal that enters the White River below Auburn.  CWA, which has agreements with local tribes, cities and homeowners to ensure water for fish and people, has completed significant improvements to the entire system.

Largest trust donation in recent memory

On January 17, 2015, CWA made a permanent donation of 684, 571 feet of water (equivalent to a football field covered with water 130 miles deep) to the state’s Trust Water Rights Program.  The water will stay in-stream for the preservation of instream flows and to protect fish habitat in a stretch of the White River that flows through the Muckleshoot Tribal Reservation.

The largest in recent memory to the trust water program, the donation completes the agreement CWA made in 2010 to donate a portion of the water rights it acquired in the purchase of Lake Tapps from Puget Sound Energy.

In addition to its permanent trust water donation, CWA donated another 154,751 acre feet of water (equivalent to an additional football field covered with water 29 miles deep) to the Temporary Trust water rights program until 2034.  The donated water stays in the White River for the benefit of fish, wildlife, recreation and the natural environment. Ecology has agreed not to approve or issue new water right permits for 20.7 miles of the Reservation Reach of the river.

Report of Examination - Ecology's decision documents

On September 15, 2010, Ecology approved and posted the final Lake Tapps Public Water Supply Project reports of exams.  The final water rights decisions and related appendices are posted below:

Related Information Sources


Lake Tapps Water Supply Project

Southwest Regional Office
Department of Ecology
PO Box 47775
Olympia WA  98504-7775
Phone 360-407-6859

Cascade Water Alliance
520 112th Ave. SE #400
Bellevue, WA  98004
Phone: 425-453-0930