Runoff (hydrology)

The processes that drive these movements are evaporation, transpiration, condensation, precipitation, sublimation, infiltration, surface runoff, and subsurface flow.

The ocean plays a key role in the water cycle as it is the source of 86% of global evaporation.

It occurs when excess rainwater, stormwater, meltwater, or other sources, can no longer sufficiently rapidly infiltrate in the soil.

Surface runoff often occurs because impervious areas (such as roofs and pavement) do not allow water to soak into the ground.

[6][7] The land area producing runoff that drains to a common point is called a drainage basin.

[11][12] Most municipal storm sewer systems discharge untreated stormwater to streams, rivers, and bays.

This excess water can also make its way into people's properties through basement backups and seepage through building wall and floors.

More precisely, it produces a surface runoff hydrograph in response to a rainfall event, represented by and input as a hyetograph.

A detailed diagram depicting the global water cycle. The direction of movement of water between reservoirs tends towards upwards movement through evapotranspiration and downward movement through gravity . The diagram also shows how human water use impacts where water is stored and how it moves. [ 1 ]
Runoff flowing into a stormwater drain
Urban runoff flowing into a storm drain