Lesson 21.3: True or False Name___________________ Class______________ Date________ Write true if the statement is true or false if the statement is false. _____ 1. Diseases caused by polluted water kill millions of people every year. _____ 2. Water pollution contributes to water shortages by making some water sources unsafe to use. _____ 3. Water pollution affects human and environmental health only in less developed countries. _____ 4. Municipal water pollution comes only from households and businesses. _____ 5. Industrial water pollutants include heavy metals and organic toxins. _____ 6. All industrial water pollutants come from factories and power plants. _____ 7. Fertilizers that run off lawns and farm fields are extremely harmful to the environment. _____ 8. The Mississippi is the only river that causes a dead zone. _____ 9. Ships at sea empty their wastes directly into ocean water. _____ 10. The most polluted areas of the ocean are coastal waters.
Lesson 21.3: Critical Reading Name___________________ Class______________ Date________ Read this passage based on the text and answer the questions that follow. Sources of Water Pollution Water pollution is any contaminant that gets into lakes, streams, or oceans. Water pollution is a worldwide problem. In less developed countries, the main source of water pollution is raw sewage that is dumped into water that people must use for drinking and bathing. In more developed countries, sources of water pollution include municipal, industrial, and agricultural sources. • Municipal sources of water pollution come from the wastewater of cities and towns. The wastewater contains many different contaminants from homes and businesses. The contaminants come from inadequately treated sewage, storm drains, septic tanks, boat sewage, and yard runoff, among other sources. • Industrial pollution comes from factories, power plants, and even hospitals. Some of the most hazardous industrial pollutants include radioactive substances, heavy metals, organic toxins, chemicals, oil and other petroleum products, and heated water. • Agricultural pollution comes mainly from runoff water. Water running over farm fields and animal pens picks up fertilizers, pesticides, and animal wastes and carries them to bodies of water such as streams, lakes, and oceans. Fertilizers deserve special mention as sources of water pollution. They are found in runoff from lawns, golf courses, and farm fields. Nutrients such as nitrates in fertilizers promote the growth of algae, so bodies of water polluted 1
www.ck12.org with fertilizers become clogged with algae. When the algae die, they decompose, and decomposition uses up all the dissolved oxygen in the water. Without oxygen, the water can no longer support aquatic organisms, including plants and fish. This creates dead zones, or areas of water in lakes and oceans that lack fish and most other aquatic organisms. Questions 1. 2. 3. 4.
What is water pollution? Identify the main cause of polluted water in less developed countries. List the three major sources of water pollution in more developed countries. Explain how fertilizers can negatively affect bodies of water such as lakes and oceans.
Lesson 21.3: Multiple Choice Name___________________ Class______________ Date________ Circle the letter of the correct choice. 1. Contaminants in municipal wastewater may come from a. b. c. d.
boats that dump sewage. storm drains. yard runoff. all of the above
2. Industrial pollutants may include all of the following except a. b. c. d.
radioactive substances from hospitals. chemicals from burning fossil fuels. heated water from power plants. sewage from home septic tanks.
3. Most ocean pollution comes from a. b. c. d.
natural processes. floating oil rigs. large ships. land.
4. Which statement is false about the April, 2010 explosion of the Deepwater Horizon drilling rig? a. b. c. d.
It caused the largest oil spill to date. It happened in the Gulf of Mexico. It occurred very close to shore. It killed 11 workers.
5. Thermal pollution occurs when a. b. c. d.
hot water is released into a body of water. very cold water is released from a reservoir. the sun heats ocean water to higher-than-normal temperatures. two of the above
6. The purpose of spraying chemical dispersants on an oil spill in the ocean is to a. help the oil mix with the water. b. absorb the oil from the surface of the water. c. prevent the oil from sticking to aquatic animals. 2
Concept 1. Water Pollution
d. cause the oil to clump together for easier removal. 7. Where do dead zones occur? a. b. c. d.
only in ocean water in all bodies of still water only in the Gulf of Mexico in many bodies of water
Lesson 21.3: Matching Name___________________ Class______________ Date________ Match each definition with the correct term. Definitions _____ 1. any contaminant that gets into lakes, streams, or oceans _____ 2. potent neurotoxin that contaminates water in San Francisco Bay _____ 3. major source of water pollution in developing countries _____ 4. area in a body of water where nothing lives because of lack of oxygen _____ 5. how most ocean pollution enters ocean water _____ 6. any change in water temperature that is unrelated to weather _____ 7. water contaminant that may leads to dead zones Terms a. dead zone b. thermal pollution c. mercury d. water pollution e. nitrate f. sewage g. runoff
Lesson 21.3: Fill in the Blank Name___________________ Class______________ Date________ Fill in the blank with the appropriate term. 1. Runoff containing fertilizer nutrients promotes the growth of __________ in bodies of water. 2. The decomposition of algae uses up dissolved __________ in the water. 3. A large dead zone in the Gulf of Mexico occurs because of pollutants carried there mainly by the __________ River. 4. __________ is the method of cleaning up oil spills by corralling and burning the oil. 5. Floating containment __________ are placed on the surface of water to trap spilled oil. 3
www.ck12.org 6. Heated water from power plants that is returned to the environment causes __________ pollution. 7. In developed countries, sources of water pollution include municipal, industrial, and __________ sources.
Lesson 21.3: Critical Writing Name___________________ Class______________ Date________ Thoroughly answer the question below. Use appropriate academic vocabulary and clear and complete sentences. Some people think that the ocean is too large to be seriously affected by pollution. Using information in the lesson, explain why this is not true.