EF Lewis is perfect, you have the Heisson as mentioned, and lower down is the 503 Bridge by Lewisville park with a great view of a 2+ rapid that can be walked and run over and over to shoot film.
Even lower down by Daybreak park is a surf wave directrly below the bridge at super high water and one upstream several yards by the playground at 1200- 2000.
I would also think East to the Spokane River plenty of bridges on the upper and lower runs. theres even a huge wave below the suspension bridge in Riverside State Park at high flows