| A | B |
|---|
| fresh water | relatively pure water; water with few dissolved salts |
| surface water | fresh water found on earth's surface |
| runoff | water that flows over land and collects in a stream or river |
| river system | a network of connected streams and rivers |
| watershed | all of the land area that supplies water to a particular river system |
| groundwater | fresh water found below Earth's surface |
| permeable | having spaces and pores that allow water or other substances to pass through |
| impermeable | not allowing water or other substances to pass through |
| aquifer | a spongelike formation of rock, sand, or gravel that holds water |
| water table | the boundary between the zone of aeration and the zone of saturation in an aquifer |
| recharge zone | an area where surface water soaks into the ground and reaches an aquifer |
| well | a channel dug into an aquifer to reach groundwater |
| water diversion | the process of moving water from its source to places where humans can use it ( e.g., homes and farm fields) |
| dam | an obstruction placed in a river or stream to block its flow |
| reservoir | an artificial lake where water for human use is stored |
| salinization | the build up of salts in the surface layers of soil |
| desalination | the process of removing salt from seawater also called desalinization |
| xeriscaping | landscaping using plants adapted to dry conditions |
| point-source pollution | pollution that comes from a specific location |
| nonpoint-source | pollution that comes from many places over a large area |
| pollution | matter or energy that is harmful to the environment |
| cultural eutrophication | the pollution of a body of water as a result of human activity; also called artificial eutrophication |
| wastewater | water that has been used in households, businesses, industries, or public facilities and drained or flushed down the pipes, as well as the polluted runoff from streets and storm drains |
| algal bloom | the rapid growth of algae in an area that can cover the surface of the water and block sunlight from reaching plants below |
| pathogen | a disease-causing organism |
| red tide | a harmful algal bloom caused by algae that produces reddish pigments |
| septic system | a method of waste water disposal |
