Across
- 4. material that makes water harmful
- 7. water above ground
- 9. many small sources of pollution
- 14. overuse of groundwater causes saltwater to seep into aquifers
- 16. frozen layer of soil in polar regions
Down
- 1. water behind a dam
- 2. body of rock or sediment that can store a lot of water
- 3. live or dead organisms added to water
- 5. one specific site of pollution
- 6. nutrients in water increases
- 8. removing harmful bacteria from water
- 10. heating of natural water results from human activities
- 11. harmful chemicals added to water
- 12. water below the ground
- 13. growth of towns and cities due to people moving from an urban area
- 15. drinkable water