Raincatcher,
Walling does have some monster Squawfish, I have caught my biggest one out of there using a floating piece of bread crust while fishing for carp, thats the only squawfish thats fooled me into thinking it was a carp.
But the Gravel Pit I am talking about is the one pretty much in front of WinCo, close to Home Depot (not on Cherry Ave), it is not exactly legal, but I have been told by the Cemex workers that they dont mind fisherman and they encourage us to run off the homeless people bringing their camps to the pond. Using bread, I have caught monster Trout (23" healthy too) and Squawfish (smallest is probably 16 inches), their are also some Monster Bass lurking the Gravel Pits.
Raincatcher, do you ever fish the Riverfront or Wallace Marine Park, they are pretty productive especially if you don't mind catching something random every cast.