Cascade Water Alliance

Lake Tapps 
Public Water Supply Project

Lake Tapps
Boat Management

Lake Tapps
Watercraft Usuage




·  The level of the lake is slowly dropping. (The lake leaks as it conveniently fills area wells with nourishing drinking, cooking, showering and toilet bowl water.)

·  Water is no longer flowing into the lake from the White River. (Don’t panic. It will begin again in the future.)

·  Water is not being released from the lake. (Ditto. See previous bullet.)

·  Depending on the weather, and the natural leakage of the lake, it is expected the level of the water in the lake should be at about 541.5 or higher through October.

·  Residents with plans to do some projects on their lake front should plan them for the January/February time period when the lake is down. That may be the last chance to take advantage of low lake levels for at least the next four years due to the Corp of Engineers’ Mud Mountain Dam Fish Passage Project.


·  September 28

Cascade will be doing a third round of chemical treatment in already designated areas.

·  Starting around November 1

Cascade will begin reducing the level of the lake to about 539 feet.

·  January 2

The lake will be lowered to 530 feet through mid to late February for work on the dikes by Cascade and projects planned by the city of Bonney Lake and Pierce County.

·  Mid to late February (Timing is dependent on completion of projects mentioned above.)

Refilling the lake will begin.

·   Spring of 2018

The Corp of Engineers’ Mud Mountain Dam Fish Passage Project will begin. This project could last up to four years. During this project, Cascade will only be able to bring the water level down to approximately 538 to 539 feet.

Lake Tapps drawdown to begin mid to lake October

Cascade Water Alliance and the Lake Tapps Community Council today announced the winter 2017/2018 drawdown schedule for Lake Tapps, and noted the long term look at future lake levels.

Initially, the lake drawdown will begin in mid to late October, lowering the lake level to approximately 539 feet through December 2017.

Cascade will then draw down Lake Tapps to 530 feet beginning Jan. 2 to accommodate several dike stability issues as well as projects for Pierce County and Bonnie Lake. The reservoir will be down until the fill begins around mid to late February.

Projects expected to be addressed include:

· Support for the integrity of Dikes 3, 4, 11 and 13;

· Inspection of the Island 21 Bridge supports;

· Replacing the Lake Tapps gauge shack piling and decking;

· New pilings at the Pierce County boat dock, and

· Fixing supports for Bonney Lake’s Vandermark Bridge.

In addition, the US Army Corps of Engineers is scheduled to award and contract for construction of the Mud Mountain Dam Fish Passage Project in spring 2018. Construction is scheduled to begin in 2018 and could last up to four years, during which time Cascade will ONLY bring the reservoir down to approximately 538 to 539 feet. Residents are urged to take this opportunity to do work on their property during this time, as there will be no further drawdowns for four years.

However, residents who wish to do any work during this draw down period must act now to obtain all the necessary permits from the City of Bonney Lake, Pierce County, and the

Department of Fish and Wildlife (if appropriate) and get a license from Cascade. These documents must be obtained prior to beginning of construction. For more information on Cascade’s licenses visit or email

Lake Tapps is a recreational gem of the region, especially for the homeowners who live near its shore. But it’s also a working reservoir owned and operated to eventually provide municipal drinking water to members of the Cascade Water Alliance. Keeping Lake Tapps clean and healthy is up to everyone who enjoys the lake today and into the future. Residents are advised that nutrients from failing septic tanks and nutrients from fertilizers and from runoff feed vegetation in the reservoir and can result in excessive algae, toxic algae blooms, reduced water clarity, and stress on fish and wildlife.

Cascade purchased the 100-plus year old White River system and Lake Tapps Reservoir from Puget Sound Energy in 2009. Since then, Cascade has invested tens of millions of dollars to keep the reservoir infrastructure reliable and the waters healthy with milfoil control.

Cascade needs the help of residents to keep Lake Tapps clean and healthy! Learn more about Cascade Water Alliance at

Algae Watch, Alerts and Information

Tacoma-Pierce County Health Department tracks Lake Tapps for possible toxic algae or bacterial contamination.

If you would like to learn more or get involved in Algae Watch, please email:

If you would like to receive alerts about environmental or human health concerns at area waterways, sign up at:

For more information about toxic algae, go to:

Call: (253) 798-6470.

Lake Tapps Reservoir is a beautiful recreational area, but it is also part of Cascade Water Alliance’s water supply system, including the lake bed (up to elevation 545 feet), the dikes, and the entire White River system.
To keep a healthy, safe reservoir, the following regulations are in place for recreational and public access:

Dikes: Dikes are closed to the public, accessible only by homeowners whose property abuts the dikes or if one has a license issued by Cascade.  All other presence on dikes is trespassing. Unlicensed structures on dikes will be removed at owner cost.

Lake Bed: To build or remodel bulkheads or docks, a Cascade license and all appropriate permits must be obtained before work can start. Unpermitted structures will be removed at owner cost.

Closed Areas: Trespassing on the dikes, within the White River Project, or on Cascade areas posted “no trespassing” will be referred to law enforcement agencies. This is for safety.
Cascade and its partners in law enforcement, fire and schools remind swimmers that the reservoir is glacier fed, and is therefore often very cold in some places. Recreation enthusiasts should call 911 if they spot trouble on the lake, trespassers, speeders, violators or people in damage.  

To assist homeowners in planning ahead for project work, Cascade has issued the following lake level plans (subject to change due to unforeseen circumstances).  The reservoir level in the summer is 542.5 feet, and most winters it is 539.5 feet.  However, in winter 2018-19, it will be down to between 530 – 532 feet for project work. 

For more information about Lake Tapps, visit 
To obtain a license for work on your property visit 
For who to call around the lake visit 

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Bear in Boat


Lake Tapps
Watercraft Usuage


Emergency: 911
253 798 4721

Option '1'

Pierce County Sheriff
Boating Hotline:
253 798 3300

Lake Tapps Hotline
253 891 5460

Cascade Water Alliance
877 299 0930


City of Bonney Lake
253 447 4344


Pierce County
Planning and Land Service
253 796 7210

Washington State
Fish and Wildlife

360 902 2200