Cedar River Mouth – Where River Meets Lake Washington

The Cedar River enters Lake Washington at the south end of the lake in Renton — a small river mouth where freshwater mixes with the lake, where salmon surge upstream every fall, and where the south lake opens into the broader Rainier Beach corridor. This is less a single launch point than a destination: a specific piece of interesting geography worth paddling to from either direction.

Access Points

From the south (Renton): The Cedar River Park area in Renton provides river access and the ability to paddle the lower river before it enters the lake. The Cedar River Regional Trail runs alongside.

Address (Renton): Cedar River Park, 1101 Bronson Way N, Renton, WA 98057

📍 Get Directions on Google Maps

From the north (Pritchard Beach): Launch from Pritchard Beach on Lake Washington (S Beer Sheva St, Seattle) and paddle south about 1.5 miles to the river mouth. This is the most straightforward approach — flat lake water the whole way, then exploring the river mouth area as a destination.

The Salmon Run

The Cedar River hosts one of the largest Chinook and coho salmon runs in the Lake Washington watershed. Fish return from the ocean through the Ballard Locks, across Lake Washington, and up the Cedar River to spawn. The peak runs:

• Chinook (King) salmon: August through October — the largest fish, often 20-40 pounds
• Coho (Silver) salmon: September through November — often the most visible from the water as they hold in the lower river before moving upstream
• Sockeye: June through August in some years

From a SUP board at the river mouth in October, you can often see coho holding just below the surface — dark shapes massing before pushing upstream. The Renton Rowing Center nearby also offers dock viewing of the returning fish.

Conditions at the River Mouth

The river mouth creates a mixing zone with slightly different water chemistry and temperature than the open lake. Current from the river can be noticeable in spring (snowmelt) and strong rain events. In summer and fall, the current is minimal and the mouth area is easy to explore on a board. Stay alert for boat traffic in the south lake and for floating debris after heavy rains.

Practical Notes

• Best visit timing: Fall for salmon; any season for the route; spring for river exploration (if current is manageable)
• From Pritchard Beach: The 1.5-mile one-way paddle from Pritchard Beach makes a clean out-and-back morning route — about 3 miles total
• Renton Rowing Center: Visible from the water near the river mouth — busy with rowing teams on weekday mornings