Across
- 3. flowing body of water
- 4. layer of gas surrounding the earth
- 6. man-made way to water plants, agriculture and crops
- 7. germ-like microorganisms found everywhere
- 9. removing salt from water
Down
- 1. water under the earth's surface
- 2. very small organisms
- 3. replacing water
- 5. amount of salt in water
- 8. keeps water clean, used in pools