Water Pollution Essay, Research Paper
Water Pollution
Water pollution has been an increasing problem over the last few years. Pollution itself is when a substance or energy is introduced into the soil, air, or water in a concentrate. Pollution comes in many forms; agricultural, urban runoff, industrial, sedimentary, animal wastes, and leeching from landfills/septic systems just to name a few. These pollutants are very detrimental to the environment. Whether they are alone or combined with another form of pollution they are very harmful. Over the last hundred years the problems with pollution have been increasing with time. This is due to both the increase in human population, and the increases in technology we have made as a society. If we plan on having our resources here for many years to come we are going to have to make some drastic changes in the way we treat the earth, and these changes will have to start with our pollutants.
Agricultural pollution is a very big contributor to water pollution. Problems we see with agriculture are applications of fertilizers, insecticides, and pesticides. We have made vast improvements in the types of chemicals we are using, as to how environmentally friendly they are. Yet even today the effects of these chemicals are very harsh, for instance:
The annual total output of pesticides in the United States is more than 2.5 billion pounds with 1500 active ingredients in some 45,000 products. Each year, approximately one billion pounds of pesticides containing more than 600 active ingredients, are applied to farms and gardens. Of this quantity, an estimated of 3.5 to 21 million pounds reach surface waters before degrading. (Rural Groundwater Contamination)
And not all of those 3.5 to 21 million pounds is removed in runoff, some of it leeches into the ground where it contaminates the groundwater supplies. This fact is very disturbing considering the fact that a large number of people that live in rural America. These people rely on these groundwater supplies for drinking water. According to the EPA at least 10% of wells contain pesticide contamination. (Water Pollution #2) These numbers don t even include the amount of chemical fertilizers that are added to fields throughout the year. When you add that number to the amount of pesticides, it becomes staggering. In 1985 the amount of fertilizer added to America s fields was 11.5 million tons (Rural Groundwater). Not only do these chemicals leech in to the soil, but they are also swept off the soils by rain and wind. When these fertilizers reach the water there is a sudden boom in plant growth. When the plants die, bacteria that need oxygen to live eat their bodies. This starts to deplete the amount of oxygen in the water for other fish and animals to live and breath, and they end up dying. Besides the chemical contamination on the farm there are major problems with animal wastes.
Over the last 30 or so years there has been an increased demand for food. Foods like pork, chicken, turkey, and beef. With the demand for meats, there is also an increased demand for grains to feed these animals. So more land is needed to grow the feed, less space is available for the feedlots. More and more of these feedlots have been popping up over the landscape. And the amounts of animals crammed into the small spaces are also increasing. There can be as few as 50 to as many as 7 million in a single confinement (Boss Hog). The animals in these confinements make much more waste than a human does. For instance, a single dairy cow can produce up to 120 lbs of wet manure a day (EPA). Think about the total amount of wastes produced in a day at one of theseconfinements. A 1000 head dairy cattle farm would yield around 120,000 lbs of waste per day. This waste is either pumped into bins, earthen lagoons, or spread onto fields as fertilizer. These waste storage facilities pose a great threat to the environment. Most of the lagoons are not properly sized or lined. This can allow the manure to seep into the ground contaminating the ground water. They can also break causing a major spill. In 1995 a North Carolina hog farm had a lagoon break through its side and spill into the New York River. The lagoon was nearly 8 acres in size and according to the EPA approximately 22 million gallons of manure was spilled (EPA). When these spills occur the animal life in the body of water they pollute is wiped out. The manure kills the fish just as the fertilizers do. They produce a major algae bloom, and when the plants die they produce a large amount of bacteria that use up the oxygen in the water causing the fish and other animals to die.
Another large contributor to water pollution is urban/industrial runoff. One of the main problems with this sort of pollution is what the pollutant is. Urban runoff and industrial pollution are a little bit different but they are close enough to be grouped together. Urban runoff deals with things like household chemicals, oils, gasoline, antifreeze, paints, and cleaners. For example, when somebody is doing spring-cleaning. All of the leftover cleaners, paints, and oils are just dumped into the gutters or down the drain. These chemicals dumped into the gutters stay there until the next rain, or snow melt. They are then washed down the storm sewers to the nearest lake or stream. When they get into the surface water the natural processes that normally break down less harmful materials cannot do anything to them. The animals and fish around the lake get exposed to the chemicals, which often are fatal to them. When the chemicals are poured down the drains they flow down the system to the areas waste water treatment plant. When this happens there is nothing that can be done to treat these pollutants. For instance, in an activated sludge system, the wastewater is pumped into holders. In these holders is the sludge , that is actually a thick liquid that contains billions of bacteria. These bacteria are supplied with oxygen that is pumped into the sludge from an outside source. The bacteria actually feed on the organic matter, but when they try to feed on the oils or chemicals they are killed. These pollutants eventually are diluted by the liquid they are in, and flushed down the system, but they are still there. And when they are in concentrated enough form they are also fatal to fish and wildlife. Industrial pollution has been a big problem for many years. Though strict laws are cutting down the amount of pollutants being dispersed into the rivers and lakes. Thousands of different industries are dumping hazardous wastes into our rivers and lakes in the form of tainted waters. They use the water for cleaning or cooling purposes, and with the dangerous pollutants still in the water it is just pumped out. Many different forms of pollutants such as benzene, chlorotoluene, ethylbenzene, nitrobenzene, styrene, trichloroethylene, and vinyl chloride are being found in our drinking water (But Not A Drop To Drink). Many of these chemicals are being monitored because of how dangerous they are. That is just the chemical side of industrial pollution. Solids are also a big problem. The construction industry discharges slurries of gypsum, cement, abrasives, metals, and poisonous solvents. (Water Pollution) Many of these are just thrown away with the normal trash, without being properly disposed of. Another form of industrial pollution is heat pollution. When certain factories or power plants use water to cool off things, or to run generators, the heated water is dumped into the nearest body of water. This heated water has a direct affect on the surroundings. It raises the dissolved oxygen level, which kills some of the native plants and animals (Water Pollution Control).
Another problem, which many people don t realize is polluting our waterways, is sedimentary pollution. Sedimentary pollution, also known as siltation, is very harmful to fish and other wildlife. Silt, by definition, are small particles that are between 0.002mm and 0.05mm in size (EPA). The silt is eroded off fields, riverbanks, or shorelines. It can also be washed off construction sites, city streets, or even just parking lots.
Silt can cause abrasions in gills, killing fish directly by interfering with their respiration; it can suffocate fish eggs and bottom dwelling organisms; and it can destroy spawning beds when it settles to the bottom of rivers and streams. (EPA)
Another problem the silt causes is making the water much less clear. This directly affects the plant life in the body of water. It decreases the amount of sunlight that can reach the plants. These plants need the sun to carry out photosynthesis, which is how they create their food. This also creates oxygen for the different inhabitants of the system.
These pollution problems we are facing today are being monitored by hundreds of different agencies, which enforce many different laws. These laws were started to help to protect the environment. Things like the Clean Water Act of 1972 help to protect the nations waters. This act sets specific standards for pollution control and water quality. Its two main goals are to eliminate the pollutants that are dumped into the nation s water, and to achieve fishable and swimmable water. This act was the first of many that have been passed to ensure water quality. The safe drinking water act of 1974 is another important act that was passed. This act made maximum levels of pollutants in the drinking water, and gave the EPA the right to enforce these standards. It also recommended certain ways to treat the contaminated water. There are hundreds of different acts and amendments that try to protect and improve the quality of our nations water. We spend huge amounts of money trying to improve and treat our water. In the United States in 1995, nearly $10 billion was spent on water and wastewater treatment alone. (Water Pollution). This figure shows just how important this is to our country.
The problems we face with pollution today are very important. Important enough for the government to pass many acts and amendments to control the amounts of pollutants that are released into our waterways. This problem has been growing with time. But with the right amount of time and a hefty chunk of cash we can make a good start at cleaning up the water of the world. Though pollution is such a widespread problem we can do our part in cleaning up the world by just doing one small thing at a time.
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