Water Pollution

1. Water Pollution Part 1 Nitrogen and Phosphorus

2. D24 – Learning Target Explain how the accumulation of mercury, phosphates and nitrates affects the quality of water and the organisms that live in rivers, lakes and oceans.

3. What is water pollution? Water pollution is any contamination of water with chemicals or other foreign substances that are detrimental to human, plant, or animal health.

4. Water Pollution • www.icee.org

5. What substances are considered pollution? These pollutants include: • fertilizers and pesticides from agricultural runoff • sewage and food processing waste • lead, mercury, and other heavy metals • chemical wastes from industrial discharges • chemical contamination from hazardous waste sites.

6. Why is clean water crucial? • Clean water is used for drinking, irrigation, industry, transportation, recreation, fishing, hunting, support of biodiversity, and personal enjoyment. • Worldwide, nearly 2 billion people drink contaminated water that could be harmful to their health. • In short … we need clean water for our health and happiness.

7. The roots of the problem … • Historically, people have used waterways to wash themselves, and to remove wastes and pollutants from populated areas. • People have depended on water to flush their waste downstream. • So, it was not fun to live downstream from anyone else!

8. Impaired Waters • These are defined as waters which are not suitable for their designated uses. • These waters that can no longer be used for drinking, irrigation, industry, recreation or fishing

9. Today’s water issues … • Our past and current practices of flushing wastes has caused our waters to be too polluted to clean themselves naturally. • Water shortages and water quality are related. If there is an increase in the amount of polluted waters, then the total amount of available clean water decreases, causing shortages.

10. The best solution to water shortages • Don’t pollute the water that you have! • If you are not impairing the clean water, then you will have more supply to use, and less likelihood of shortages. DUH!

11. Impaired Waters in Connecticut Newington

12. What are some of the causes of impairment? • Nitrogen and phosphorus are deposited in the waters from things such as fertilizer and detergents • Siltation occurs, which means that waters are dirtied by erosion from places such as farms and construction sites • Acidification occurs through atmospheric deposition (acid rain) or runoff from mines.

13. What is the most common type of impairment? • The most common impairment is eutrophication caused by excessive inputs of phosphorus and nitrogen. • What is eutrophication? • This is the over-fertilization of surface waters with N and P, which were previously scarce.

14. Eutrophication http://www.epa.gov/bioiweb1/aquatic/classify.html

15. What happens as a lake starts to become eutrophic? • With an overabundance of N and P, the algae can overtake the lake, turning it green. This event is called an algae bloom, and is an early sign of eutrophication • Overgrowth of plants choke water movement.

16. What are the later stages of eutrophication? • When plants and algae use up all of the resources, they die, and use up all of the available oxygen as they decompose. • This causes oxygen shortages (called anoxia) which can kill fish.

17. Negative effects of eutrophication • Fish will die in the summer due to anoxia. • The water will not be clear. • The water will taste bad. • The water will smell bad!

18. How does this occur? When pollutants flow into a body of water, it happens by one of two ways. Point sources • These are specific traceable sources, such as an effluent pipe from a factory Non-point sources • These are from a wide range of areas, and will enter the water in several ways, such as surface water flow and atmospheric deposition. • These are tough to track.

19. Non-Point Source Examples • www.lakescientist.com

20. Non-point N and P continued … • Fertilizers are a major contributor of phosphorus. • Not all of the nutrients are used up by the crops, and the remainder run off fields during rainstorms

21. Livestock Farms • Livestock feed lots cause an enormous accumulation of animal waste. These nutrients will make their way to water during rain.

22. Non-point N and P continued … • Urban run-off • This includes water originating from construction sites, fertilized lawns, and septic systems. • Atmospheric deposition of N • This results from the burning of fossil fuels

23. What can we do to help? • Fertilizer applications must be reduced to reasonable levels, so that excess nutrients are not introduced to the environment • Vegetation must be planted near lakes and streams to help uptake the extra nutrients before they enter the lake • Restoration of wetlands also helps clean up extra nitrogen

24. What can we do to help? • Retention ponds should be created between farms and waterways • In urban areas, sewers must be maintained, streets swept and waste properly disposed • Reduction of usage of fossil fuels • Research must be performed on this problem, so that appropriate regulations can be created.

25. Reference • Baskin, Y. (ed) (1998). Nonpoint pollution of surface waters with phosphorus and nitrogen. Issues in Ecology, 3, 1-12.