How does overland flow lead to soil erosion?
Rill Erosion As overland flow moves downslope, it concentrates due to surface microtopography. The soil materials detached within rills and sediment delivered from interrill areas are transported by rill flow. Once rills have formed, substantial amounts of erosion may occur, resulting in a loss of soil productivity.
What is overland flow and throughflow?
Overland flow transfers water through the basin either as sheetwash, across the surface, or in tiny channels called rills. Beneath the surface, water is transferred via throughflow, which is the movement of water through the lower soil towards rivers, and groundwater flow.
What is the difference between overland flow and interflow?
Interflow is sometimes used interchangeably with throughflow; however, throughflow is specifically the subcomponent of interflow that returns to the surface, as overland flow, prior to entering a stream or becoming groundwater. …
Who is responsible for overland flow?
A property owner is required to accept natural overland flow from adjoining properties or public land and must not divert or redirect the flow from its natural path on to neighbouring properties. A downstream property owner cannot erect any type of barrier that interferes with the path of overland flow.
How does overland flow occur?
Overland flow can occur if soil water draining down the slope is forced to the surface by the complete saturation of the soil lower down the slope, and this condition is usually present only near the base of the slope.
Is interception a flow?
Stores include puddles, rivers, lakes (surface storage), glaciers, soil storage and groundwater storage along with water stored on vegetation (interception) following precipitation. Transfers or flows include percolation, overland flow, infiltration, stemflow, throughflow and overland flow.
Who is responsible for water runoff?
In its simplest form, the civil law rule says that landowners are strictly liable for altering the natural drainage of surface water. The rule thus is the exact opposite of the common enemy rule. Landowners have no right to alter drainage, and they have the right not to be injured by others altering the drainage.
What is an easement to drain water?
Easement to drain water – an easement granting the legal right for a “body” (usually a public authority such as a local council) to drain stormwater, rainwater, spring water, soakage water or seepage water through the land burdened.
Why is overland flow important?
Overland flow is a very important aspect of the water cycle and can be generated under two different physical mechanisms. On the other hand, vegetation protects the soil and creates pathways for water infiltration through its roots and thus can reduce overland flow in an area (Beven, 2001).
Which is more common overland flow or throughflow?
Rain falling on soil-covered drainage basin, in which throughflow dominates, will encounter a much more varied areal distribution of soil moisture than Horton postulated. Overland flow and surface erosion are most common, therefore, in locations marginal to the existing channel network and particularly in the hollows at stream heads.
Where does overland flow and surface erosion occur?
Overland flow and surface erosion are most common, therefore, in locations marginal to the existing channel network and particularly in the hollows at stream heads. In these hollows the position of the channel tip is determined by a balance between fluvial cutting and basal fill along the valley axis by slope processes.
How is drainage density related to overland flow?
Drainage density is controlled by the extension of the drainage network which, in turn, is controlled by throughflow and overland flow near the foot of slopes and, particularly, in stream-head hollows. This implies that drainage density controls the behaviour of stream hydrographs, and not the reverse as postulated by Carlston (1963 and 1966).
What kind of erosion is caused by Raindrop splash?
The Modified USLE model has been used to calculate the total upland erosion resulted by raindrop splash, overland flow erosion and rill erosion, while three models, Yang, Laursen-Copeland and Ackers-White, are suitable to simulate load streams’ sediment transport potential.