Is there a reason you can't build a low water crossing. I have 2 that I made and they are virtually trouble free. Just dig down below the creek bed a couple of foot and backfill with heavy rip rap then smaller rip rap to the original creek bed level. You can make the approaches as shallow or steep of slope as you want. During big rain events the water will carry in some silt and leave a layer in the approaches but once a year with a blade and that is an easy fix. I highly recommend them. The main requirement is to keep stuff level or below natural creek bed level.