Drainage or flood discharge that leaves an area as surface flow or as pipeline flow, having reached a channel or pipeline by either surface or subsurface routes Generally, surface water entering river, lakes, or reservoirs < back to top S
(1) The portion of rainfall that is not absorbed by the deep strata and not lost to vegetation or evaporation It is that which finds its way into streams as surface flow (2) The total stream discharge of water (quantity or rate), including both surface and sub surface flow, usually expressed in acre feet or in cubic feet per second per square mile of drainage area
(1) That part of the precipitation, snow melt, or irrigation water that appears in uncontrolled surface streams, rivers, drains or sewers Runoff may be classified according to speed of appearance after rainfall or melting snow as direct runoff or base runoff, and according to source as surface runoff, storm interflow, or ground-water runoff (2) The total discharge described in (1), above, during a specified period of time (3) Also defined as the depth to which a drainage area would be covered if all of the runoff for a given period of time were uniformly distributed over it
That part of the precipitation that appears in uncontrolled surface streams, drains, or sewers It is the same as streamflow unaffected by artificial diversion, imports, storage, or other works of man in or on the stream channels
That part of the precipitation that appears in surface streams It is the same as streamflow unaffected by artificial diversions, storage, or other works of man in or on the stream channels Runoff may be classified as follows
Water traveling across the ground surface, caused by heavy rains or irrigation If the surrounding ground is sloped toward a pond, surface runoff can wash dirt and garden chemicals into the water
n: Surface water effluent (usually from precipitation but may be from human activities such as irrigation) that moves too quickly to be absorbed into the ground It flows down contour gradients to enter stream and river systems, carrying with it anything light enough to be borne in the volume of water, which may be light after a small rain or tremendous in the wake of a storm, when even large boulders and trees get swept up in the runoff When runoff travels over deforested or unplanted agricultural lands, it carries away large quantities of topsoil Runoff from agricultural areas often carries heavy doses of biocides , fertilizers, and other nutrients, which can lead to eutrophication when introduced into aquatic systems
water from rain, snow melt, or irrigation that flows over the ground and returns to streams, lakes, or wetlands It can collect pollutants from air or land and carry them to the receiving waters
Water from rain, snow melt, or irrigation that flows over the ground surface and returns to streams It can collect pollutants from air or land and carry them to the receiving waters S
The flow of water, usually from precipitation, which is not absorbed into the ground It flows across the land and eventually runs to stream channels, lakes, oceans, or depressions or lowpoints in the Earth's surface The characteristics that affect the rate of runoff include rainfall duration and intensity as well as the ground's slope, soil type, and ground cover Runoff can pick up pollutants from the air and land, carrying them into the streams, lakes, etc
The amount of precipitation not absorbed into the ground which flows into the sea It can cause fluctuations in the sea level, for example in a harbour at the mouth of a river Sea level along open coasts is not noticeably affected by it
That part of precipitation, snow melt, or irrigation water that is not absorbed by soil and which drains or flows off the land into streams or other surface waters
Water from rain or irrigation that flows across, rather than into, the land Runoff increases as the amount of impervious surfaces increases Runoff often carries pollutants, such as pesticides, excess nutrients, and sediments It is a major vehicle for nonpoint source pollution In undeveloped forest land, little rain runs off as plant cover and roots allow rainwater to seep slowly into the soil In developed suburban and urban land, the increased amount of impervious surfaces decreases the absorption of rainfall and increases runoff Runoff flushes pollutants contained on the impervious surfaces and in the rainwater itself into nearby streams High amounts of runoff can erode stream banks and cause flooding After reaching the receiving water body, pollutants from runoff degrade water quality
Water from rain, snowmelt, or irrigation that flows over the ground surface and returns to streams, running off the land to the stream It includes the water and everything it picks up along the way
The portion of the precipitation on the land which ultimately reaches the streams especially the water from rain or melted snow that flows over the surface