| A | B |
|---|
| surface water | fresh water on Earth's land surface |
| river system | flowing network of water |
| watershed | area of land drained by a river |
| groundwater | water in sediment and rock formations |
| aquifer | underground formation that contains groundwater |
| recharge zone | water percolates through this into an aquifer |
| potable | water is treated to make it drinkable |
| 3% | amount of fresh water on Earth |
| 1% | amount of fresh water available for our use |
| reservoir | artificial lake formed behind a dam |
| point-source pollution | can be traced to a source(septic tanks, factories, industry, etc) |
| non-point source pollution | comes from many different sources - difficult to trace |
| eutrophication | natural process in which nutrients build up in water and types of organisms that live in the water begin to change |
| biomagnification | build up of pollutants at higher levels of the food chain |
| pathogen | bacteria |
| global uses of fresh water | residential and industrial |
| artificial eutrophication | caused by phosphates and fertilizers |
| 1972 Clean Water Act & Water Quality Act | laws designed to improve water quality |
| activities on land | most of the pollutants in the ocean |
| Mississippi River | largest watershed in the US |
| 1990 Oil Pollution Act | all tankers in US waterways must be double-hulled by 2015 |
| chlorine | kill or limit bacteria growth |
| parasitic worms | pathogen |
