Surface runoff (also known as overland flow or terrestrial runoff) is the unconfined flow of water over the ground surface, in contrast to channel runoff (or stream flow). It occurs when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in …

Jun 8, 2019 · When water "runs off" the land surface, that’s runoff! Due to gravity, the water you wash your car with runs down the driveway as you work, and rain runs downhill. Runoff is an important component of the water cycle.

Jun 6, 2018 · Runoff from agricultural land (and even our own yards) can carry excess nutrients, such as nitrogen and phosphorus into streams, lakes, and groundwater supplies. These excess nutrients have the potential to degrade water quality. Why might stormwater runoff be a problem?

Runoff is the flow of water across the earth, and is a major component in the hydrological cycle. Runoff that flows over land before reaching a watercourse is referred to as surface runoff or overland flow. Once in a watercourse, runoff is referred to as streamflow, channel runoff, or river runoff. Urban runoff is surface runoff created by ...

Oct 19, 2023 · Runoff occurs when there is more water than land can absorb. The excess liquid flows across the surface of the land and into nearby creeks, streams, or ponds. Runoff can come from both natural processes and human activity. The most familiar type of …

Jan 16, 2025 · Stormwater runoff is generated from rain and snowmelt that flows over land and does not soak into the ground. Runoff can pick up and deposit harmful pollutants into streams, lakes, and groundwater.

Runoff, in hydrology, quantity of water discharged in surface streams. Runoff includes not only the waters that travel over the land surface and through channels to reach a stream but also interflow, the water that infiltrates the soil surface and travels by means of gravity toward a stream channel

May 23, 2024 · Runoff picks up fertilizer, oil, pesticides, dirt, bacteria and other pollutants as it makes its way through storm drains and ditches - untreated - to our streams, rivers, lakes and the ocean. Polluted runoff is one of the greatest threats to clean water in the U.S.

Particularly important to hydrologists are the water cycle components precipitation, infiltration, and runoff. Precipitation is water that falls from the atmosphere to the Earth’s surface. Infiltration is precipitation that soaks into the soil.

Jan 15, 2025 · We present an assessment of water supply across the conterminous United States (CONUS), Alaska, Hawaii, and Puerto Rico covering water years 2010–20. Our analysis drew on two national hydrologic models, the National Hydrologic Model Precipitation-Runoff Modeling System and the Weather Research and Forecasting model hydrologic modeling system.