Lake Levels

Important reminder – residents should watch Lake Tapps Reservoir levels and make appropriate decisions regarding removing boats and other property from the water. Due to a construction project at the White River diversion point, no additional water will be added to the reservoir. Cascade will use this opportunity to undertake work to inspect and repair, if necessary, the facilities that make up the conveyance system to the reservoir. The project will improve the reliability and water quality of the water that flows through the conveyance system to the Lake Tapps Reservoir.

Cascade brought the reservoir levels to just below 543 feet in late August to allow the reservoir to stay as full as possible through the end of the recreation season on September 30, while maintenance work is being carried out upstream of the reservoir and no additional water is capable of being added.

Starting November 1, Cascade will actively drawdown reservoir levels to approximately 539.5 feet for the fall and winter.  This allows Cascade to perform necessary maintenance on the dikes and ensures safety from wind, storm, and wave action during the winter months.

Cascade maintains seasonal recreational water levels between elevation 541.5 feet and 543 feet from April 15 to September 30.  The 2025 spring refill is anticipated to begin in mid-February.

If residents are planning work on their property, this is a good time to obtain the appropriate, required permits and a Cascade license prior to beginning any work. Further, residents should keep in mind as they do work on their property, especially bulkheads, that Cascade has the authority to raise reservoir levels to elevation 543 feet under current water rights, so any new or modified bulkheads should be built with the consideration that the reservoir level will be up to 543 feet.

Residents can monitor overall reservoir water levels by clicking here.

For more information on Lake Tapps/Cascade agreements visit http://www.cascadewater.org/lake_tapps_agreements.php.

For information regarding licenses for project work click here.

USGS Links:

Lake Tapps Level Gage 

White River Gage

Cascade has owned and operated the Lake Tapps Reservoir since 2009. During that time, Cascade has managed lake levels in accordance with the provisions of the Lake Tapps Reservoir Water Rights, which incorporate relevant provisions from the 2009 Agreement regarding Lake Tapps between Cascade Water Alliance and the Lake Tapps Community and the 2008 White River Management Agreement between the Puyallup Tribe of Indians, the Muckleshoot Indian Tribe and Cascade Water Alliance.

The Water Rights and the agreements provide for Cascade to maintain recreational reservoir levels or normal full pool, between elevation 541.5′ and 543.0′ (gage height) from April 15 through Sept. 30.

Typical fall drawdown to a lake level of approximately elevation 538′ – 539′ is sufficient to protect the integrity of the Lake Tapps dikes and for any routine inspections. This minimizes the wear on the valves in the power house during fall drawdown and the risk of problems refilling the Lake Tapps Reservoir during periods of water shortage.

Specific dike or other maintenance projects will require Cascade to reduce the lake level in the fall and winter to approximately elevation 533′ to 535′ (some projects may require the level to be lower).