Yes, that is the only "real" ramp on the river. The ramp at the forks has been out for years.
The only hazard I'm aware of is the "ramp" just below the hwy and the sweeper below it. The water has dropped so I have not been in the river since the fourth.
Also there is no shuttle service for the area. Bring a friend with a vehicle or a scooter. Perhaps you can also hook up with another drifter. Since it's a good ten-twelve mile drift.

Or if you just want to catch chum you can access the river up near Schafer park and along the road near Cook Cr.