Here is some Delta Bridge clearance information.
Mokelumne River Bridge (Highway 12): HW 8' / LW 11'
Little Potato Slough Bridge (Terminous/Highway 12). HW 35' / LW 38'
Bethel Island Bridge (non-opening) Hw 15' / LW 19'
Here's a photo of the Terminous Bridge taken by a Philpott? Any relation?
Attachment 4640