“The feet belong to unfortunate crewmen who have washed overboard from vessels in the Pacific freight lanes.”
Sounds plausible but it doesn’t actually add up. You see, they have managed to identify a good number of the owners of said feet, and they were all locals from around the sound, not seamen on oceangoing vessels. I believe many were joggers who disappeared, if I remember correctly.
Kind of makes sense, since they are finding feet in athletic shoes, which are more associated with joggers than crewmen on boats.
Looks like they've ID'd some but not all. Of those, several apparently committed suicide - a woman who jumped from a bridge up river, and a man whose family said he was suicidal. The coroner (who may or may not know his business, depends) has ruled out foul play in inquests.
I would be surprised if a serial killer was able to keep up his predations undiscovered from 1985 to the present day. And apparently the discovery of feet in shoes in the area dates back well into the 1800s, so he'd be a long-lived fellow if he existed.
Is there a problem in the area with high tides and/or tidal bores? or some other water hazard that might drown joggers on the beach? I dimly remember reading about rogue waves or something similar in the area.
Doesn't explain the rest though.