Water PollutionPart 1

Nitrogen and Phosphorus

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

D24 – Learning Target

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

What is water pollution?

www.icee.org

Water 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.

What substances are considered pollution?

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.

Why is clean water crucial?

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!

The roots of the problem …

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

Impaired Waters

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.

Today’s water issues …

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.

The best solution to water shortages

DUH!

Impaired Waters in Connecticut

Newington

1. Nitrogen and phosphorus are deposited in the waters from things such as fertilizer and detergents

2. Siltation occurs, which means that waters are dirtied by erosion from places such as farms and construction sites

3. Acidification occurs through atmospheric deposition (acid rain) or runoff from mines.

What are some of the causes 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.

What is the most common type of impairment?

Eutrophication

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

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.

What happens as a lake starts to become eutrophic?

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.

What are the later stages 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!

Negative effects of eutrophication

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 factoryNon-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.

How does this occur?

www.lakescientist.com

Non-Point Source Examples

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

Non-point N and P continued …

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

Livestock Farms

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

Non-point N and P continued …

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

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.

What can we do to help?

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

Reference