River Flows & Lake Levels

River flows as of Sept. 26

To get real-time flow information, click the links for each river, then scroll down the page to “Select data to graph” and click “Discharge, cubic feet per second.”

Cowlitz River below Mayfield Dam – about 2,380 cubic feet per second (cfs)
Mayfield flow forecast (typically updated on Monday and Thursday afternoons) as of Monday, Sept. 25: We plan to maintain the current discharge through Wednesday, then increase it to about 3,500 cfs on Thursday — remaining at that level through the weekend. Read more about the flow reduction here.
*Click here to sign up for our Cowlitz River Project email list.

Nisqually River below LaGrande Dam – about 705 cfs

Wynoochee River above Black Creek – about 403 cfs

Wynoochee River at Grisdale – about 832 cfs

Green River at Palmer (Tacoma Water’s headworks) – about 285 cfs

North Fork Skokomish River below Cushman Dam No. 2 – about 206 cfs
Click here to sign up for our Cushman Hydro Project email list.

Check out water safety resources. River flows can change at any time.

Subscribe to available Water Alerts provided by the US Geological Survey.

Lake levels and boat launches as of Sept. 26

Riffe Lake – 710.29 feet of elevation (maximum of approx. 749 ft)
*Mossyrock Park boat launch is open (one lane). The dock is not usable. One lane is usable to about 720 feet – it is closed; the other is usable to about 708 feet. The dock is usable to about 724 feet. The day-use area is open. The swim area is not usable (it is usable to about 728 feet).
*Taidnapam North boat launch is closed. The lane is usable to about 720 feet and the dock is usable to about 731 feet. We will extend the dock’s anchor point by the end of 2023; it will reach about 726 feet.
*Kosmos boat launch and parking lot are closed due to operational constraints. The launch is not usable below 747 feet and cannot be extended.
*Taidnapam Park boat launch is closed due to operational constraints. It is not usable below 760 feet and cannot be extended.
*Public access to the Mossyrock Dam North Shore Fishing Trail is closed due to safety concerns. Learn more at  MyTPU.org/Cowlitz under “Latest News.”
*Click here to sign up for our Cowlitz River Project email list.

Alder Lake – 1,174.38 feet of elevation (maximum of 1,207 ft)
*Alder Lake Park boat launch is open. The day-use area is open. The launch is usable to approximately 1,171 feet. 
*Rocky Point boat launch (hand-launch only), day-use area, and campground are open.
*Stacel Point day-use area is open.
*Sunny Beach Point day-use area and swim area are open. (They are open May 15 – Sept. 15.)

Mayfield Lake – may fluctuate 4 feet weekly, between 421 and 425 feet of elevation (maximum of 425 ft)
*Mayfield Lake Park boat launch and day-use area are open.

Lake Cushman – 727.6 feet of elevation (maximum of 738 ft)
*The Lake Kokanee boat launch is open.
*Get information about Skokomish Park at Lake Cushman.
*Click here to sign up for our Cushman Hydro Project email list.

Wynoochee Lake – 768.52 feet of elevation (maximum of 800 ft)
*The day-use area is open.

Coho Campground and boat launch are open (typically from mid-May to October).

Get current campfire rules on the Parks & Recreation homepage.

River flows could change at any time so boaters and anglers should remain alert for this possibility.