The Bethel Island bride is an "arc", right? It's higher in the middle than it is at the edges. It's about 15 feet at the edges, I think it's more than 19 in the middle. However you only have to go under it if you go the "west route" through the sloughs to get to Sunset Harbor.
I've been at Sunset Harbor when the current was running and it's substantial, like 4+ knots so planning is important.
1968 Selmer Series 9 B-flat and A clarinets
1962 Buesher "Aristocrat" tenor saxophone
Piper One Design 24, Hull #35; "Alpha"