Let's redirect the water! Not easy.
The center of lower Colonial is almost flat -- a "flowage" with no clear channel. By putting down some left over tree trunks the water will spread out onto a large area. Then it can soak into the ground where natural microbes will clean it up.
When it finally gets to the river, the water will be much cleaner and the salmon fingerlings will do much better.
Some ducks loved the new water flow from the day after the City moved some logs. (Thank you again PRCS!)