| Term | Definition |
| drainage canal | a channel to take dirty used water away from fields |
| irrigation canal | a channel to take clean water to fields |
| herbicide | a chemical poison to kill plants |
| pesticide | a chemical poison to kill bugs |
| sewage | dirty, used water |
| effluent | dirty water flowing from the place where it has been used |
| seepage | water that leaks out and slowly moves deeper underground |
| groundwater | water that is underground--often used for drinking |
| aerated | water that is bubbled or sprayed to mix it with oxygen |
| running water | clean water piped to houses and businesses |
| sanitation system | a series of pipes to take dirty water away from houses and businesses |
| salinity | amount of salt in water |
| coliform | bacteria that causes numerous stomach and intestinal diseases |
| tannery | a place where animal skins are prepared for use as fabric |
| enforcement | to watch closely and use punishments to make people do something |
| water treatment | cleaning up dirty water |
| aquifer | a huge underground area of water |