Water runs clear in mountains, but stream bed is full of gravel and boulders along channel. Where bed load is much greater than suspended load, the channel form is often braided , with lots of small channels running down the coarse stream bed. Capacity is maintained by steep gradient, which helps move the bed load, especially during floods. Flat, or shallow gradient, channel flows over old flood deposits in a floodplain. Large channels size and efficient channel shape.
Most load is transported as suspended load, rather than bed load.
Rivers are opaque, muddy in appearance, channel bed primarily sandy. Where suspended load is much greater than bed load, the channel form is often meandering , with a single channel that wraps sinuously across a floodplain. Capacity is maintained by large, efficient channel, which allows higher mean velocity to erode and transport much sediment in suspension. Dissolves basic cations, like calcium in limestone. Hydraulic action of water against channel edge dislodges and lifts sediments.