Watershed

6. an area of low-lying ground adjacent to a river, formed mainly of river sediments and subject to flooding.
7. a brook, stream, or artificially constructed water channel.
10. is an area of land that drains all the streams and rainfall to a common outlet such as the outflow of a reservoir, mouth of a bay, or any point along a stream channel.
11. is the line that separates neighboring drainage basins.
13. the area from which rainfall flows into a river, lake, or reservoir.
14. A point source is a single, identifiable source of pollution, such as a pipe or a drain.
15. rain, snow, sleet, or hail that falls to the ground.
17. is the spot where a smaller stream or river, known as a tributary, feeds into a larger stream or river, known as the main stem.

1. a tributary stream of a river close to or forming part of its source.
2. or affluent is a stream or river that flows into a larger stream or main stem (or parent) river or a lake.
3. is the result of an aquifer being filled to the point that the water overflows onto the land surface.
4. is caused by rainfall or snowmelt moving over and through the ground, it picks up and carries natural and human-made pollutants, depositing them into lakes, rivers, wetlands, coastal waters and ground waters.
5. the area drained by a river and all its tributaries, also called catchment area.
8. excessive richness of nutrients in a lake or other body of water, frequently due to runoff from the land, which causes a dense growth of plant life and death of animal life from lack of oxygen.
9. is the water found underground in the cracks and spaces in soil, sand and rock. It is stored in and moves slowly through geologic formations of soil, sand and rocks called aquifers.
12. The rate of flow, usually of a fluid, measured in volume per unit time.
16. is an underground layer of water-bearing permeable rock, rock fractures or unconsolidated materials (gravel, sand, or silt) from which groundwater can be extracted using a water well.