JohnnyCoho - That is an excellent spot.

It's the old Lyman Ferry about 2 miles past the Day Creek store to the left off of the South Skagit Hwy. It's not clearly marked and looks a bit like a private drive but just drive straight down the nicer looking dirt road to the end. The fish stack there by the thousands.

Some other spots with easy drive to access are the spud house SW of Mt Vernon off the Penn RD. and the Gardner Rd access in Burlington.