Fish are on a schedule too. 

At the Percival Creek fish passage project at Sapp Road, crews are working within a tight timeline to open the stream to fish by Aug. 31. 

Work happening within the ordinary high-water level of the creek must take place within what’s sometimes called a “fish window” – an in-water work window established by the Washington Department of Fish & Wildlife to minimize impacts to fish during sensitive periods in their life cycle and during typical low flow in the creek. 

Prior to construction, thousands of fish were safely moved downstream from the project site, and the stream was diverted around the construction zone. A new, much wider culvert was installed using stream simulation methodology outlined in the 2013 WDFW water crossing design guidelines.  

The new culvert is engineered to maintain water flow at the natural pace of the stream - making it possible for salmon to swim upstream to spawn. 
Fish will be able to pass freely through the culvert at Sapp Road after August 31. 

Environmental consultants, representatives from Squaxin Island Tribe, and biologists from WDFW confirm that Percival Creek has high-quality habit for fish with plenty of microorganisms for food, suitable water quality, and cool water. Biologists from the Wild Fish Conservancy completed environmental DNA testing in Percival Creek and identified evidence of salmon up to the point where the culvert was on Sapp Road. 

Next, crews will complete the culvert walls and rebuild the roadway above the stream. with Sapp Road scheduled to reopen for motorists in mid-October. 

The Percival Creek Fish Passage Barrier Removal Project at Sapp Road is one huge milestone for the City of Tumwater's ongoing work to restore natural salmon runs in the community. The City's Water Resources & Sustainability team has been working toward healthier streams and salmon habitat in the community since the 1990s. 

And the work continues. The next planned fish passage project will correct a stream barrier at Somerset Hill and is anticipated in 2029. Learn more about Fish Passage Projects.