What is the solution?
Since the 1990s, there has been amazing change in the Great Lakes. This was due to cleanup work done on both sides of the U.S.-Canada border.
Making Laws to Reduce Pollution In 1972, the United States and Canada created the first Great Lakes Water Quality Agreement. They pledged to clean up and protect the Great Lakes ecosystem. The first cleanup efforts involved point-source pollution. This is water pollution from a single place, such as a discharge pipe at a sewage treatment plant or a factory.
New laws put strict limits on the amount of phosphorus and other chemicals that industries and sewage treatment plants could release into the waters. Soap makers stopped putting phosphorus into detergents. Industries stopped dumping oil and other pollutants into rivers. Other laws banned the use of a number of toxic chemicals, like PCBs and DDT.
The new laws worked. The Cuyahoga River was no longer flammable, or easy to catch on fire. Algae growth was greatly reduced. The lakes turned from green back to blue. PCBs and DDT in the food chain declined. And, as the amount of DDT in fish dropped, the bald eagle made a comeback.
Continuing Pollution Challenges One great challenge in the Great Lakes today is non-point-source pollution. This is pollution that does not come from a single location. When rainfall, snowmelt, and irrigation water run across the land, the water picks up pollutants from the soil. Runoff from storms also picks up waste from industrial and construction sites.
Old toxic waste dumps also pollute. Many contain poisons that leak into waterways. There are as many as 250 dumps on the shores of the Niagara River alone.
Pollution from the air damages watersheds as well. Mercury, among other things, is released into the air when coal is burned. This highly toxic metal falls back to Earth mixed with rain or as dust. It then enters waterways and the food web.
Canada and the United States are working to clean up non-point-source pollution. They have made new laws to limit harmful chemicals that go into the air, water, and soil. They are also cleaning up toxic sediment in waterways. Toxic sediment is polluted soil that has settled to the bottom of lakes and rivers. Removing such sediment is both difficult and costly.
The best way to deal with pollution is to prevent it. Today, education programs encourage prevention. People in industry and farming are using fewer harmful chemicals. Consumers are also choosing products that are safer for the environment.
What else can be done?
Protecting Precious Wetlands Like forests, wetlands were also lost during the settlement of the Great Lakes region. A wetland is an area where the soil is usually wet all year. Examples are marshes, bogs, and swamps. Wetlands provide habitats for a wide variety of wildlife. They also help to control flooding during storms.
In the past, wetlands were viewed as worthless bogs. Over time, more than half of the wetlands in the region disappeared. Only in recent years did people begin to see the value of wetlands habitat.
Today, public and private groups are working to protect wetland habitats. One way is by creating nature preserves on existing wetlands. Another is by teaching landowners how to protect wetland areas. In some places, developers must create more than one acre of new wetland for every acre they destroy.
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Making Laws to Reduce Pollution In 1972, the United States and Canada created the first Great Lakes Water Quality Agreement. They pledged to clean up and protect the Great Lakes ecosystem. The first cleanup efforts involved point-source pollution. This is water pollution from a single place, such as a discharge pipe at a sewage treatment plant or a factory.
New laws put strict limits on the amount of phosphorus and other chemicals that industries and sewage treatment plants could release into the waters. Soap makers stopped putting phosphorus into detergents. Industries stopped dumping oil and other pollutants into rivers. Other laws banned the use of a number of toxic chemicals, like PCBs and DDT.
The new laws worked. The Cuyahoga River was no longer flammable, or easy to catch on fire. Algae growth was greatly reduced. The lakes turned from green back to blue. PCBs and DDT in the food chain declined. And, as the amount of DDT in fish dropped, the bald eagle made a comeback.
Continuing Pollution Challenges One great challenge in the Great Lakes today is non-point-source pollution. This is pollution that does not come from a single location. When rainfall, snowmelt, and irrigation water run across the land, the water picks up pollutants from the soil. Runoff from storms also picks up waste from industrial and construction sites.
Old toxic waste dumps also pollute. Many contain poisons that leak into waterways. There are as many as 250 dumps on the shores of the Niagara River alone.
Pollution from the air damages watersheds as well. Mercury, among other things, is released into the air when coal is burned. This highly toxic metal falls back to Earth mixed with rain or as dust. It then enters waterways and the food web.
Canada and the United States are working to clean up non-point-source pollution. They have made new laws to limit harmful chemicals that go into the air, water, and soil. They are also cleaning up toxic sediment in waterways. Toxic sediment is polluted soil that has settled to the bottom of lakes and rivers. Removing such sediment is both difficult and costly.
The best way to deal with pollution is to prevent it. Today, education programs encourage prevention. People in industry and farming are using fewer harmful chemicals. Consumers are also choosing products that are safer for the environment.
What else can be done?
Protecting Precious Wetlands Like forests, wetlands were also lost during the settlement of the Great Lakes region. A wetland is an area where the soil is usually wet all year. Examples are marshes, bogs, and swamps. Wetlands provide habitats for a wide variety of wildlife. They also help to control flooding during storms.
In the past, wetlands were viewed as worthless bogs. Over time, more than half of the wetlands in the region disappeared. Only in recent years did people begin to see the value of wetlands habitat.
Today, public and private groups are working to protect wetland habitats. One way is by creating nature preserves on existing wetlands. Another is by teaching landowners how to protect wetland areas. In some places, developers must create more than one acre of new wetland for every acre they destroy.
Great work! You're almost done! Click here to go to the last tab...then you'll soon be on BrainPop!