Across
- 4. Any deliberate disposal at sea of wastes or other matter from vessels, aircraft, platforms or other man-made structures at sea
- 6. an analytical parameter representing the amount of dissolved oxygen consumed by aerobic bacteria growing on the organic material present in a water sample at a specific temperature over a specific time period.
- 9. 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.
- 10. a barrier constructed to hold back water and raise its level, forming a reservoir used to generate electricity or as a water supply.
- 11. land consisting of marshes or swamps; saturated land
- 13. eroded material that is being transported by water, settles out of the water column onto the surface, as the water flow slows.
- 15. an artificial waterway constructed to allow the passage of boats or ships inland or to convey water for irrigation.
- 16. uses require that water be left in the stream
- 17. Illnesses caused by microorganisms in untreated or contaminated water.
- 18. prevention of wasteful use of a resource
Down
- 1. the modification of a natural river channel
- 2. form of precipitation that has unusually elevated levels of hydrogen ions
- 3. a process which removes and eliminates contaminants from wastewater and converts this into an effluent that can be returned to the water cycle.
- 5. involve withdrawing water, as for municipal and industrial uses
- 6. the use of either naturally occurring or deliberately introduced microorganisms or other forms of life to consume and break down environmental pollutants, in order to clean up a polluted site
- 7. occurs when, over a period of years, more water is pumped from a groundwater basin than is replaced from all sources
- 8. a hydrological tool used to quantify the flow of water in and out of a system.
- 12. water that exists underground in saturated zones beneath the land surface
- 14. the process of removing salt from seawater
