Water Pollution and Treatment

1. Water Pollution and Treatment Types of water pollution 1) Sediment: the #1 pollutant of U.S. waterways Soil, sand, and gravel washed into waterways Contributors: Agriculture, construction Results: streams choked with sand/silt, rather than rocky bottoms. Coral reefs are covered with silt, killing them off

4. Mississippi River Delta

8. Madagascar Yellow River, China

9. 2) Oil: discharged either intentionally or by accident. Intentional discharges include ships washing out oil tanks, pumping the liquid overboard. Technically illegal, but still occurs quite a bit. Dumping anything down a storm drain allows it to reach a local waterway quickly. Oil from oil changes should be recycled, and can easily be re-used for other purposes.

10. Accidental Oil Discharge Leakage from tanks, pipelines, ships, autos Exxon Valdez: 1989, spilled @12 million gallons of crude oil into Prince William sound, in Alaska. Resulting Damage: 100,000- 650,000 sea birds, 28% sea otters, 15% harbor seals, unknown numbers of fish and other creatures. Every day in the U.S., several million gallons of oil are leaked by automobiles onto streets, and into storm drains.

18. 3) Waterborne disease Carried to waterways through runoff Diseases such as cryptosporidium ( an intestinal parasite). E. coli bacteria, found in the intestinal tract of most animals. Also called fecal coliform bacteria, washed into waterways through storm drains, or leaked out of sub-standard sewers and septic systems

19. The 1993 Milwaukee Cryptosporidium outbreak was a significant distribution of the Cryptosporidium protozoan in Milwaukee Wisconsin, and the largest waterborne disease outbreak in documented United States history. Over 100 deaths were attributed to this outbreak, mostly among the elderly and immunocompromised people, such as AIDS patients

20. Outdated sewer systems, such as in Wilmington, combine runoff with sewers. In a heavy rain event, the combined amount of liquid overwhelms the sewer plant, and is not treated. The liquid is dumped, untreated, into the Christina River near its junction with the Delaware River. A plan is underway to separate the two systems, and allow the storm drains to empty directly into the river.

24. Other sources of fecal coliform: Farms, especially those with large numbers of cattle or horses. Large scale feed operations, such as hog farms and chicken farms. (C.A.F.O.) Legislation has been enacted to prevent the discharge of untreated waste to waterways, but unintentional discharges still occur. Other animal waste, such as from dogs and cats

30. 4) Nutrients The two main nutrients that act as pollutants are Nitrogen and Phosphorous. Sources: In urban areas, fertilizer, detergents, and sewer plant discharges are the main sources. High phosphate soaps used to be a bigger issue, but detergents now have much less phosphate than they once did. Although sewage treatment plants eliminate much of the organic matter, they still release large amounts of nitrogen into waterways.

31. Where Water Contaminants Come From

32. Surface Water Pollution • Water Pollutants are emitted from • Point Sources • Distinct and confined sources such as pipes from industrial or sites • Nonpoint Sources • Diffused and intermittent • Ex) runoffs from streets

41. Biochemical Oxygen Demand The amount of oxygen required for biochemical decomposition process Usually caused by a large input of organic material or nutrients. 3 Zones : A Pollution Zone, where the initial pollution is introduced An Active Decomposition Zone, where decomposers utilize the organic material, as well as Oxygen A Recovery Zone, where nutrients are gradually used up, and conditions gradually return to normal.

43. In rural areas, excess fertilizer from farm fields is the source of most nutrient pollution. Nutrient pollution also comes from animal farms, especially pigs and chickens. (C.A.F.O.) In the past, it was a common practice for farmers in DE to use large amounts of chicken manure as fertilizer, to get rid of the excess. Eventually the excess fertilizer found its way into the back bays, and caused huge algal blooms.

44. Eutrophication of Waterways Eutrophication is the process where a body of water receives a high level of nutrients, which leads to the eventual death of the waterway. a) Waterway receives too much N or P b) Nutrients cause a huge increase in algae in the waterway. c) Beneficial plants are shaded out, and die off d) Algae also eventually dies off, causing a drop in oxygen levels. e) Because of low oxygen levels, other organisms die off, and cause a further degradation.

45. Eutrophication is a natural process, but is very slow in nature. When the process is accelerated by humans, it is called cultural eutrophication. One of the results of C. E. is the production of H2S (hydrogen sulfide). This is formed when anaerobic decomposition takes place. Eutrophication can be reversed of the nutrient load is reduced, and the waterway receives enough oxygen to allow decomposition to occur aerobically, forming CO2.

47. Total Maximum Daily Load Total Maximum Daily Load is a calculation of the maximum amount of a pollutant that a body of water can receive and still meet water quality standards. TMDL’s are determined by the E.P.A., based on the ability of the body of water to recover, and the type of pollutant.

48. Delaware’s inland bays (Indian River and Little Assawoman Bay) are both highly eutrophic in the summer months. -High levels of N and P from farming, increased flow from sewage treatment facility. -Warmer water holds less dissolved oxygen than cold water. Result: large fish kills, when schools of fish are trapped in areas of low oxygen.

49. Blind-ended canals and marinas are the worst areas, because they receive very little fresh ocean water. Solar powered devices that mix the water have been tried with some success. The ultimate answer: less N and P, and more access to the ocean. Waste management is now mandated for chicken farmers, and studies on new access to the ocean have been done.