Suspended load
A load is the term for particles carried by a stream or river.
A bed load is a collection of large particles of sediment which are carried along the bottom of a stream.
Particles of sand and pebbles that are less dense than water are carried by a stream through a process called suspension. The flow of the water exerts enough force to keep these lighter particles suspended in the water and move them downstream. The particles are lifted off the streambed and transported until the flow of the water slows down or they encounter an obstacle that causes them to settle.
Sediments are carried as the following loads: dissolved, suspended, and bed. A dissolved load is composed of ions in solution. These ions are usually carried in the water all the way to the ocean. ... Particles that are too large to be carried as suspended loads are bumped and pushed along the stream bed, called bed load.
The measure of the largest particles a stream can carry is capacity.
For a given mass of stream water, its kinetic energy is proportional to the speed of flow squared. So, for example, if we double the speed of the stream its kinetic energy will increase by four fold. And kinetic energy can be found from the average force acting on some mass (e.g., those "particles") over a distance. So one can conclude that a faster moving stream can exert more force on the stones and debris in that stream. Which means the faster moving stream is more likely to be able to actually lift and carry larger heavier particles than the slower stream can. NOTE: This discounts particles that can float in a static stream, like wood chips, as they are carried without the stream flowing.
As a particle size gets larger in a stream, the force needed to move the particle in the suspended water column is greater. The velocity dictates which size particles are able to be picked up from the bed and carried as stream load. Some particles, such as fine silts, require very little velocity and can be dissolved on their own without moving water. Larger, coarse rock particles may require extremely high velocities which may only be reached during storm events, depending on the stream of course.
Little sediments are carried by the eroding stream
load or stream load.
load
Sediment that is carried by a stream along the bottom of its channel.
... particles.... particles.... particles.... particles.