HEC-RAS 6.0 and later include a "Clear Water" boundary condition. The clear water boundary condition is just a simple way to define a no-sediment boundary. The model will bring flow in at this cross section but no sediment.
A clear water boundary can simulate a high trap-efficiency dam outlet or other flow boundaries without appreciable sediment.
Clear Water Scour
This condition usually causes scour, unless the reach has a fixed bed, is pass-through, or heavily armored.
