Is swimming allowed in the river, or is the river too shallow?

I agree! The river is usually way to high and fast moving. Power boats only.. Go up river about 10 minutes and swim at American Falls marina beach to swim. 😎

Swimming is not allowed from any part of Massacre Rocks State Park! Period. SUPB, canoes, boats and other craft are allowed and free life vest rentals are available at the boat dock. #massacrerocksstatepark

the river is to high fast

Would NOT swim... Go to the American Falls Reservoir instead...

The currents are unbelievably strong in that area so I believe there are signs posted to not swim. The river there is deceiving, looks flat and calm but when you get close nothing but swirling eddies. There may be swim spots near the campground but from the visitor center to the boat ramp it warns against swimming.