Protecting Our Water Keeping Our Water Healthy

Transcription

1 Protecting Our Water Keeping Our Water Healthy Draw a bubble map about "Why Water is Important in Our Daily Lives". Include at least 5 reasons. Compare answers with your neighbors, noting similarities and differences. Add new answers to your bubble map based on your discussion. Use your bubble maps to help you in our class discussion. Underneath your bubble map, write a paragraph (at least 5 sentences) about: "Why should we protect the water we have on Earth?" Why Water is Important in Our Daily Lives 1

2 Protecting Our Water Water is a precious resource that needs to be managed and protected so it can stay a sustainable resource. U.S. Government agencies have set water quality standards to make sure water stays clean and safe. Wastewater also has to be treated to keep pollutants from getting into aquatic ecosystems or drinking water. Water Regulations Many laws have been passes to protect water quality in the U.S. The Clean Water Act (1972) protects surface waters. Main goal: "the protection and propagation of fish, shellfish, and wildlife and recreation in and on the water". Provides money for the construction and maintenance of wastewater treatment plants. Environmental Protection Agency sets and enforces quality standards for wastewater released by industry and local governments. They also set up educational programs to help reduce non point source pollutants. The Safe Drinking Water Act (SDWA) is the main federal law that ensures the quality of Americans' drinking water. Under SDWA, EPA sets standards for drinking water quality and requires many actions to protect drinking water and its sources: rivers, lakes, reservoirs, springs, and ground water wells. 2

3 Water Regulations oceans The US Marine Protection, Research, & Sanctuaries Act(1972) forbids the dumping of materials that can harm human health or marine ecosystems Oil Pollution Act all oil tankers operating in US waters must have double hulls. (Passed after Exxon Valdez ran aground and spilled 260,000 barrels of crude oil in Prince William Sound, Alaska in Oil spills actually only make up 5% of oil pollution in the oceans. Most oil pollution comes from improper disposal of motor oil and oil run off from roadways. Even a little oil can have a big impact. Just 5.5 liters of oil can pollute 1 million gallons of water! 3

4 NC Water Quality Standards Every state has their own water quality standards, which can meet or exceed federal standards. Some states have specific protections for sensitive areas, such as fisheries, lakes, or streams. NC surface water standards apply to lakes and streams important to wildlife, or used for recreation (fishing or boating). NC Water Quality Standards ug = micrograms, 1/1,000,000 of a gram Measure of Water Quality Trout Free Waters Trout Waters Chlorophyll a < 40 ug/l < 15 ug/l Dissolved oxygen > 5.0 mg/l daily > 6.0 mg/l ph Temperature < 29 o C 32 o C < 20 o C Toxic Substances Arsenic < 50 ug/l < 50 ug/l Lead < 25 ug/l < 25 ug/l Mercury ug/l ug/l Pesticides DDT ug/l ug/l Dieldrin ug/l ug/l PCBs ug/l ug/l 4

5 Monitoring waters can help scientists figure out what types of pollution are common. If chlorophyll a, phosphorous or nitrate levels are high, or dissolved oxygen is low, nutrient run off may be the cause. Agricultural run off can lead to high pesticide levels. A low ph could be caused by acid rain or mine drainage. Industries releasing warm water can raise temperatures. Water quality standards are set to protect ecosystems. Scientists monitor water quality standards by looking at standards. If values are too low or too high, scientists can try to find, eliminate or fix the problem. To protect water quality, scientists need to find pollution sources. Water Treatment Wastewater is water that runs into drains, which may contain sewage and chemicals from homes and businesses, or pollutants from industries. Treating wastewater helps protect water quality. A wastewater treatment plant is a facility that processes water to remove wastes, and then releases clean water into a lake or stream. Treatment plants prevent pollutants from entering bodies of water and kill microbes that could spread disease. 5

6 Water treatment plants remove trash, skim floating substances like oil off the top, remove other wastes and pollutants, and in some cases add chlorine or other chemicals to make sure all diseases are killed. Then, the safe water is released. Some homes treat their wastewater by using septic systems. Pipes carry wastewater from a farm or home into an underground tank. Solid materials sink to the bottom, where they are mostly broken down by bacteria. Any materials not broken down must be pumped out every few years. Liquid wastewater is carried out of the septic tank into a drain field, pipes buried under gravel or crushed rock. The wastewater flows out of the pipe, through the gravel which filters some dissolved waste materials out. Microorganisms also clean the water as it trickles through the soil. 6