Most large rivers carry the largest part of their load in suspension. Indeed, the muddy appearance created by suspended sediment is the most obvious portion of a stream's load (Figure S.11). Usually only fine particles consisting of silt and clay can be carried this way, but during a flood, sand and even gravel-size particles are transported as well. Also, during a flood, the total quantity of material carried in suspension increases dramatically, as can be verified by anyone whose home has been a site for the deposition of this material.