sources of water pollution

sources of water pollution

While to many people clean water may seem limitless and everywhere, to many others this is not so. Water pollution is a serious issue facing hundreds of millions of people world-wide, having harmful effects on the lives of those people. Water is not in unlimited supply and cannot just be made fresh when it is wanted. Water is actually a limited resource, and for many people, fresh, unpolluted water is hard to find. A limited resource is one that we use faster than we can remake it. It is a resource that can be used up. Water pollution happens when contaminants enter water bodies. Contaminants are any substances that harm the health of the environment or humans. Most contaminants enter the water because of humans. Surface water (river or lake) can be exposed to and contaminated by acid rain, storm water runoff, pesticide runoff, and industrial waste. This water is cleaned somewhat by exposure to sunlight, aeration, and microorganisms in the water. Groundwater (private wells and some public water supplies) generally takes longer to become contaminated, but the natural clean- ing process also may take much longer. Groundwater can be contaminated by disease-producing pathogens, careless disposal of hazardous household chemical-containing products, agricultural chemicals, and leaking underground storage tanks. Water pollution can cause harmful effects to ecology and human health. Shown is the pollution in Jakarta, Indonesia. Natural events, like storms, volcanic eruptions and earthquakes can cause major changes in water quality. But human-caused contaminants have a much greater impact on the quality of the water supply. Water is considered polluted either when it does not support a human use, like clean drinking water, or a use for other animals and plants. The overgrowth of algae, known as an algal bloom, can result from the runoff of fertilizer into bodies of water. This excess of nutrients allows the algae to grow beyond control, bring harm to the rest of the ecosystem. The main sources of water pollution can be grouped into two categories: Point source pollution results from the contaminants that enter a waterway or water body through a single site. Examples of this include untreated sewage, wastewater from a sewage treatment plant, and leaking underground tanks. Nonpoint source pollution is contamination that does not come from a single point source. Instead, it happens when there is a buildup of small amounts of contaminants that collect from a large area. Examples of this include fertilizer runoff from many farms flowing into groundwater or streams.

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questions

water is an unlimited resource.

a. true

-->  b. false

many people do not have access to fresh unpolluted water.

-->  a. true

b. false

when is water considered polluted?

a) when it does nor support a use for animals or plants

b) when it does not support a human use

c) when it is not safe to drink.

-->  d) all of the above

what is a potential contaminant of groundwater.

a) agricultural chemicals

b) hazardous household products

c) disease-producing pathogens

-->  d) all of the above

which of the following is an example of point source pollution?

a) acid rain

-->  b) untreated sewage

c) fertilizer runoff

d) pathogen contamination

which of the following is an example of nonpoint source pollution?

a) underground storage tanks

b) untreated sewage

-->  c) fertilizer runoff

d) wastewater

what is the primary cause of an algal bloom?

-->  a) runoff of fertilizer into bodies of water

b) leaking underground storage tanks

c) acid rain

d) pesticide runoff

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