Kitsap Health District officials say sewage spilled into the water as a result of a break in the Highway 305 South sewer force main around 10:30 a.m.
The break occurred while a city contractor was digging to replace the pipe.
A temporary bypass stopped the spill by 1:30 p.m., and crews will fix the pipe once tide levels lower on Monday.
All people and pets are warned to stay out of the water until testing shows the water is safe. Swimming beaches are also closed until further notice.