Works Cited

Krantz, David and Kifferstein, Brad.WATER POLLUTION AND SOCIETY.

University Of Michigan. <

INTRODUCTION

Comprising over 70% of the Earth’s surface, water is undoubtedly the most precious natural resource that exists on our planet. Without the seemingly invaluable compound comprised of hydrogen and oxygen, life on Earth would be non-existent: it is essential for everything on our planet to grow and prosper. Although we as humans recognize this fact, we disregard it by polluting our rivers, lakes, and oceans. Subsequently, we are slowly but surely harming our planet to the point where organisms
are dying at a very alarming rate. In addition to innocent organisms dying off, our drinking water has become greatly affected as is our ability to use water for recreational purposes. In order to combat water pollution, we must understand the problems and become part of the solution.

POINT AND NONPOINT SOURCES

According to the American College Dictionary, pollution is defined as: to make foul or unclean; dirty. Water pollution occurs when a body of water is adversely affected due to the addition of large amounts of materials to the water. When it is unfit for its intended use, water is considered polluted. Two types of water pollutants exist; point source and nonpoint source. Point sources of pollution occur when harmful substances are emitted directly into a body of water. The Exxon Valdez oil spill best illustrates a point source water pollution. A nonpoint source delivers pollutants indirectly through environmental changes. An example of this type of water pollution is when fertilizer from a field is carried into a stream by rain, in the form of run-off
which in turn effects aquatic life. The technology exists for point sources of pollution to be monitored and regulated, although political factors may complicate matters. Nonpoint sources are much more difficult to control. Pollution arising from nonpoint
sources accounts for a majority of the contaminants in streams and lakes.

CAUSES OF POLLUTION

Many causes of pollution including sewage and fertilizers contain nutrients such as nitrates and phosphates. In excess levels, nutrients over stimulate the growth of aquatic plants and algae. Excessive growth of these types of organisms consequently clogs our waterways, use up dissolved oxygen as they decompose, and block light to deeper waters.
This, in turn, proves very harmful to aquatic organisms as it affects the respiration ability or fish and other invertebrates that reside in water.
Pollution is also caused when silt and other suspended solids, such as soil, washoff plowed fields, construction and logging sites, urban areas, and eroded river banks when it rains. Under natural conditions, lakes, rivers, and other water bodies undergo Eutrophication, an aging process that slowly fills in the water body with sediment and organic matter. When these sediments enter various bodies of water, fish respirationbecomes impaired, plant productivity and water depth become reduced, and aquatic organisms and their environments become suffocated. Pollution in the form of organic
material enters waterways in many different forms as sewage, as leaves and grass clippings, or as runoff from livestock feedlots and pastures. When natural bacteria and protozoan in the water break down this organic material, they begin to use up the oxygen dissolved in the water. Many types of fish and bottom-dwelling animals cannot survive when levels of dissolved oxygen drop below two to five parts per million. When this occurs, it kills aquatic organisms in large numbers which leads to disruptions in the food chain.

Polluted River

The pollution of rivers and streams with chemical contaminants has become one of the most crucial environmental problems within the 20th century. Waterborne chemical pollution entering rivers and streams cause tremendous amounts of destruction.

Pathogens are another type of pollution that prove very harmful. They can cause many illnesses that range from typhoid and dysentery to minor respiratory and skin diseases. Pathogens include such organisms as bacteria, viruses, and protozoan. These pollutants enter waterways through untreated sewage, storm drains, septic tanks, runoff from farms, and particularly boats that dump sewage. Though microscopic, these pollutants have a tremendous effect evidenced by their ability to cause sickness.

Nonpoint source pollution is a fancy term for polluted runoff. Water washing over the land, whether from rain, car washing, or the watering of crops or lawns, picks up an array of contaminants including oil and sand from roadways, agricultural chemicals from farmland, and nutrients and toxic materials from urban and suburban areas. This runoff finds its way into our waterways, either directly or through storm drain collection systems. The term nonpoint is used to distinguish this type of pollution from point source pollution, which comes from specific sources such as sewage treatment plants or industrial facilities. Scientific evidence shows that although huge strides have been made in cleaning up major point sources, our precious water resources are still threatened by the effects of polluted runoff. In fact, the Environmental Protection Agency has estimated that this type of pollution is now the single largest cause of the deterioration of out nation’s water quality.

Effects of Runoff

The effects of polluted runoff are not limited to large lakes or coastal bays. In fact, chances are you don’t have to look any farther than your neighborhood stream or duck pond. Water pollution in your town, and perhaps in your own backyard, can result in anything from weed-choked ponds to fish kills to contaminated drinking water.

There’s not much chance that you can ignore this problem, even if you want to. Concern over polluted runoff has resulted in an ever-increasing number of state and federal laws enacted over the last five years. At the federal level, a permit program for stormwater discharges from certain municipalities and businesses is now underway. In addition to implementing this federal program, many states have passed laws altering local land use (planning and zoning) processes and building codes to address the problem of polluted runoff. The bottom line is that both polluted runoff and its management are likely to affect you and your community in the near future.

Causes of Polluted Runoff

Polluted runoff is the cumulative result of our everyday personal actions and our local land use policies. Here’s a brief rundown on the causes and effects of the major types of pollutants carried by runoff.

Pathogens: Pathogens are disease-causing microorganisms, such as bacteria and viruses, that come from the fecal waste of humans and animals. Exposure to pathogens from direct contact or ingestion of water can cause a number of health problems. Because of this, bathing beaches are closed, and boil water alerts are issued when testing reveals significant pathogen levels. Pathogens wash off the land from wild animals, farm animals, and pet waste, and can also enter our waterways from improperly functioning septic tanks, leaky sewer lines, and boat sanitary disposal systems.

Nutrients: Nutrients are compounds that stimulate plant growth, like nitrogen and phosphorous. Under normal conditions, nutrients are beneficial and necessary, but in high concentrations, they can become an environmental threat. Nitrogen contamination of drinking water can cause health problems, including "blue baby" syndrome. Over fertilization of ponds, streams, and lakes by nutrients can lead to massive algal blooms, the decay of which can create odors and rob the waters of life-sustaining dissolved oxygen. Nutrients in polluted runoff can come from agricultural fertilizers, septic systems, home lawn care products, and yard and animal wastes.

Sediment: Sand, dirt, and gravel eroded by runoff usually ends up in stream beds, ponds, or lakes where they can alter stream flow and decrease the availability of healthy aquatic habitat. Poorly protected construction sites, agricultural fields, roadways, and suburban gardens can be major sources of sediment.

Toxic Contaminants: Toxic contaminants are substances that can harm the health of aquatic life and/or human beings. Toxins are created by a wide variety of human practices and products, and include heavy metals, pesticides, and organic compounds like PCBs. Many toxins are very resistant to breakdown and tend to be passed through the food chain to be concentrated in top predators. Fish consumption health advisories are the result of concern over toxins. Oil, grease, and gasoline from roadways and chemicals used in homes, gardens, yards, and on farm crops, are major sources of toxic contaminants.

Debris: Trash is without a doubt the simplest type of pollution to understand. It interferes with enjoyment of our water resources and, in the case of plastic and polystyrene foam, can be a health threat to aquatic organisms. Typically this debris starts as street litter that is carried by runoff into our waterways.

ADDITIONAL FORMS OF WATER POLLUTION

Three last forms of water pollution exist in the forms of petroleum, radioactive substances, and heat. Petroleum often pollutes waterbodies in the form of oil, resulting from oil spills. The previously mentioned Exxon Valdez is an example of this type of water pollution. These large-scale accidental discharges of petroleum are an important cause of pollution along shore lines. Besides the supertankers, off-shore drilling operations contribute a large share of pollution. One estimate is that one ton of oil is spilled for every million tons of oil transported. This is equal to about 0.0001 percent. Radioactive substances are produced in the form of waste from nuclear power plants, and from the industrial, medical, and scientific use of radioactive materials. Specific forms of waste are uranium and thorium mining and refining. The last form of water pollution is heat. Heat is a pollutant because increased temperatures result in the deaths of many aquatic organisms. These decreases in temperatures are caused when a discharge of cooling water by factories and power plants occurs.

Effects of Oil Spills

We have all seen pictures and videos of wildlife covered in black, sticky oil after an oil spill. These pictures are usually of oiled birds. Many people are not aware that it is not just birds that get oiled during a spill. Other marine life such as marine mammals can also suffer from the effects of an oil spill. Even small spills can severely affect marine wildlife.

Not all oils are the same. There are many different types of oil and this means that each oil spill is different depending on the type of oil spilt. Each oil spill will have a different impact on wildlife and the surrounding environment depending on:

  • the type of oil spilled,
  • the location of the spill,
  • the species of wildlife in the area,
  • the timing of breeding cycles and seasonal migrations,
  • and even the weather at sea during the oil spill.

Oil affects wildlife by coating their bodies with a thick layer. Many oils also become stickier over time (this is called weathering) and so adheres to wildlife even more. Since most oil floats o nthe surface of the water it can effect many marine animals and sea birds. Unfortunately, birds and marine mammals will not necessarily avoid an oil spill. Some marine mammals, such as seals and dolphins, have been seen swimming and feeding in or near an oil spill. Some fish are attracted to oil because it looks like floating food. This endangers sea birds, which are attracted to schools of fish and may dive through oil slicks to get to the fish.

Oil that sticks to fur or feathers, usually crude and bunker fuels, can cause many problems. Some of these problems are:

  • hypothermia in birds by reducing or destroying the insulation and waterproofing properties of their feathers;
  • hypothermia in fur seal pups by reducing or destroying the insulation of their woolly fur (called lanugo). Adult fur seals have blubber and would not suffer from hypothermia if oiled. Dolphins and whales do not have fur, so oil will not easily stick to them;
  • birds become easy prey, as their feathers being matted by oil make them less able to fly away;
  • marine mammals such as fur seals become easy prey if oil sticks their flippers to their bodies, making it hard for them to escape predators;
  • birds sink or drown because oiled feathers weigh more and their sticky feathers cannot trap enough air between them to keep them buoyant;
  • fur seal pups drown if oil sticks their flippers to their bodiesk
  • birds lose body weight as their metabolism tries to combat low body temperature;
  • marine mammals lose body weight when they can not feed due to contamination of their environment by oil;
  • birds become dehydrated and can starve as they give up or reduce drinking, diving and swimming to look for food;
  • inflammation or infection in dugongs and difficulty eating due to oil sticking to the sensory hairs around their mouths;
  • disguise of scent that seal pups and mothers rely on to identify each other, leading to rejection, abandonment and starvation of seal pups; and
  • damage to the insides of animals and birds bodies, for example by causing ulcers or bleeding in their stomachs if they ingest the oil by accident.

Oil does not have to be sticky to endanger wildlife. Both sticky oils such as crude oil and bunker fuels, and non-sticky oils such as refined petroleum products can affect different wildlife. Oils such as refined petroleum products do not last as long in the marine environment as crude or bunker fuel. They are not likely to stick to a bird or animal, but they are much more poisonous than crude oil or bunker fuel. While some of the following effects on sea birds, marine mammals and turtles can be caused by crude oil or bunker fuel, they are more commonly caused by refined oil products.

Oil in the environment or oil that is ingested can cause:

  • poisoning of wildlife higher up the food chain if they eat large amounts of other organisms that have taken oil into their tissues;
  • interference with breeding by making the animal too ill to breed, interfering with breeding behaviour such as a bird sitting on their eggs, or by reducing the number of eggs a bird will lay;
  • damage to the airways and lungs of marine mammals and turtles, congestion, pneumonia, emphysema and even death by breathing in droplets of oil, or oil fumes or gas;
  • damage to a marine mammal's or turtle's eyes, which can cause ulcers, conjunctivitis and blindness, making it difficult for them to find food, and sometimes causing starvation;
  • irritation or ulceration of skin, mouth or nasal cavities;
  • damage to and suppression of a marine mammal's immune system, sometimes causing secondary bacterial or fungal infections;
  • damage to red blood cells;
  • organ damage and failure such as a bird or marine mammal's liver;
  • damage to a bird's adrenal tissue which interferes with a bird's ability to maintain blood pressure, and concentration of fluid in its body;
  • decrease in the thickness of egg shells;
  • stress;
  • damage to fish eggs, larvae and young fish;
  • contamination of beaches where turtles breed causing contamination of eggs, adult turtles or newly hatched turtles;
  • damage to estuaries, coral reefs, seagrass and mangrove habitats which are the breeding areas of many fish and crustaceans, interfering with their breeding;
  • tainting of fish, crustaceans, molluscs and algae;
  • interference with a baleen whale's feeding system by tar-like oil, as this type of whale feeds by skimming the surface and filtering out the water; and
  • poisoning of young through the mother, as a dolphin calf can absorb oil through it'smothers milk.

Animals covered in oil at the beginning of a spill may be affected differently from animals encountering the oil later.For example, early on, the oil maybe more poisonous, so the wildlife affected early will take in more of the poison. The weather conditions can reduce or increase the potential for oil to cause damage to the environment and wildlife. For example, warm seas and high winds will encourage lighter oils to form gases, and will reduce the amount of oil that stays in the water to affect marine life.

The impact of an oil spill on wildlife is also affected by where spilled oil reaches. For example, fur seal pups are affected more than adults by oil spills because pups swim in tidal pools and along rocky coasts, whereas the adults swim in open water where it is less likely for oil to linger. Dugongs als feed on seagrass along the coast and therefore be more affected by oil spills.