What Is River Runoff?

••• Chatchai Limjareon/iStock/GettyImages

River runoff refers to all water that comes into a river water system from sources such as rainfall, snowmelt and groundwater. Runoff includes water flowing over the land into the water system, water that sinks into the soil to join the water system, as well as water that flows from the river to a larger body of water, such as a sea or ocean.

Regions

River runoff feeds into rivers, which then feed into seas. Runoff for different continents can be calculated, with tropical regions, such as the Amazon and the Congo-Zaire basin, producing more runoff than nontropical regions. Three factors influence the volume of river runoff: location, precipitation and evaporation.

Urban Runoff

When rain falls on unpaved earth it soaks into the ground, replenishing the aquifer (groundwater repository). In urban areas, when rain falls on paved ground, it does not soak into the ground but rushes over the paved surface to a stream or river. This process is called "urban runoff."

Changing Conditions

Urban runoff often contains more pollutants than natural runoff. It also feeds into the water system more quickly, bringing polluted water first into smaller bodies of water, like rivers, then into oceans and seas. Increases in urban runoff and decreases in natural river runoff reflect the increase of developing countries in the world, and the growing impact of mass urbanization.

Related Articles

Waterborne Pollutants
How to Remove Total Dissolved Solids From Drinking...
Brine Vs. Conductivity
Positive Effects of Floods
The Average Rainfall in a Fresh Water Ecosystem
How Are River Rocks Formed?
Is Hydropower a Non-Renewable or Renewable Resource?
How to Remove Total Dissolved Solids From Drinking...
Water pH & Pollution
How to Calculate Hectares
Environmental Hazards of Limestone Mining
How to Convert CV to GPM
How to Find Mass Percentage
Advantages & Disadvantages of Constructing Dams
What Environment Is Likely to Form Siltstone or Shale?
How Does Erosion Affect Landforms?
Types of Eutrophication
Importance of Rain Water
Facts About Basins
What Is the Unit for Enthalpy?

Dont Go!

We Have More Great Sciencing Articles!