Stream Loads and Erosion

Streams or rivers are bodies of water that constantly travel from its source, which is usually a mountain or an underground source, towards an exit point into the sea. These bodies of water carry different kinds of materials. There are three kinds of loads that streams carry: Dissolved, Suspended, and Bed Loads. Dissolved Loads appear invisible because they compose of the smallest particles. These are transported by the stream in the form of chemical ions.

Dissolved Loads can result from alteration of minerals from chemical erosion. It may also be a result of groundwater seepage into the stream. Suspended Loads are materials left dangling in the stream since they are too big to dissolve yet too small to sink to the stream bed. The flow of the stream keeps these particles suspended. Suspended Loads are usually the result of materials eroded by hydraulic action and erosion from the channel itself.

Bed Loads are the biggest materials that can be found lying at the bottom of the stream. Due to stream flow, Bed Loads are gradually transported in two ways: Traction (scooting and rolling) and Saltation (bounce-like movement). The transportation of Dissolved Loads are least affected by changes in stream velocity. As they are the smallest particles that can be found in streams, they will still be transported even under low stream flow since they are not big enough to settle down.

Bigger loads are harder to transport hence requiring greater stream velocity. Bed Loads are the main contributors to stream erosions. Since they are the biggest among the three loads, they are able to dislodge materials from the stream bed when they are transported through Traction and Saltation. They can also hit the walls of the stream as they move. Bed Loads also erode the channel through the process of abrasion as they scoot and roll around the stream bed when they are transported.