We ended up walking mainly amongst the buildings because the trail around the more forested area was mostly under water. In 2 hours, we wandered around approximately 2 miles with lots of stops to look at the surroundings.
There is also a disc golf course there and some people were out playing. I think it would be more fun without so much water. Also seems like a great place for some flat running.
Afterwards we headed to Sedro-Woolley for some lunch. Just after we ordered, a hard rain started falling. Great timing!