fresh water on Earth's land surface

flowing network of water

area of land that is drained by a river

water that is found beneath Earth's surface in the spaces in sediment and rock formations

underground formation that contains groundwater

percentage of the total volume of a rock that has spaces (pores)

the ability of rock or soil to allow water to flow through it

area of Earth's surface from which water percolates down into an aquifer

safe to drink

organisms that cause illness or disease

built across rivers to control the rover's flow

when water is dammed an artificial lake is formed... known as a

process of removing salt from sea water

introduction of chemical, physical, or biological agents into the water.

pollution discharged from a single source.

comes from many different sources that are often difficult to identify

water that contains waste from homes or industry

when inorganic plant nutrients enter th water for sewage runoff

can occur when power plants and other industries use water in their calling systems and then discharge the warm water into a lake or river.

The accumulation of pollutants at successive levels of the food chain