Is this Water Recycled Sewage?
Name_______________Date________
Directions: Before reading, in the first column, write “A” or “D” indicating your agreement or
disagreement with each statement. As you read, compare your opinions with information from the article.
In the space under each statement, cite information from the article that supports or refutes your
original ideas. Your answers must be in your own words.
Me
Text
Statement
1. Wastewater treatment plants remove bacteria and viruses.
2. The first stage of wastewater treatment is based on physical properties of
waste material, including solubility and density of the waste material.
3. Bacteria are detrimental in all stages of the wastewater treatment process.
4. The denitrification process removes only nitrogen compounds from the
wastewater.
5. Salts can be removed from wastewater by reverse osmosis.
6. Red pipes are used internationally to identify recycled water.
7. Recycled water has been used to re-supply dried-up geysers.
8. There are some drawbacks to using chlorine to disinfect water.
9. We have been able to keep recycled wastewater out of all major bodies of
water in the United States.
Sewage: The Hottest New Resource? Organize your thoughts as you read
Directions: As you read, please complete the chart below describing the steps for recycling wastewater.
Step & Name
1.
Description
Chemical Explanation
2.
3.
4.
Sewage: The Hottest New Resource? Answer these questions on your own paper, in
your own words.
1. What are the different sources or constituents of wastewater (sewage) that leave a home?
2. What are the four stages of wastewater treatment?
3. What three properties of waste material in sewage allow for separation in the physical treatment
stage?
4. What are the three steps used by bacteria to convert nitrogen-containing compounds into free
nitrogen gas (N2) that escapes into the atmosphere?
5. What uses are made of non-potable wastewater that has undergone final treatment?
6. How is non-potable wastewater used to generate electricity?
7. What is reverse osmosis as used in the treatment of disinfected effluent?
8. What is removed from disinfected effluent using reverse osmosis?
9. What is meant by “recharging” through the use of sanitized (disinfected) effluent?
10. What is one of the drawbacks in using chlorine as a disinfectant for wastewater treatment?
Drugs Down the Drain: The Drugs You Swallow, the Water You Drink
Name_______________Date________
Directions: Before reading, in the first column, write “A” or “D” indicating your agreement or
disagreement with each statement. As you read, compare your opinions with information from the article.
In the space under each statement, cite information from the article that supports or refutes your
original ideas. Your answers must be in your own words.
Me
Text
Statement
1. Pharmaceuticals have been found in U.S. drinking water at doses up to onetenth of the therapeutic dose.
2. There is no evidence that dissolved pharmaceuticals harm fish.
3. Wastewater treatment plants effectively remove pharmaceuticals from water.
4. Detectable levels of pharmaceuticals, insecticides, and fire retardants are
found in less than 50% of U. S. waterways.
5. Chlorine can react with pharmaceuticals to form toxic compounds such as
chloroform.
6. Changing the pH level of water has no effect on the effectiveness of chlorine
to remove some drugs.
7. Activated charcoal filters and ozone remove many unwanted chemicals from
drinking water.
8. Ozone treatment continues to work even after water is treated with ozone.
Drugs Down the Drain: Organize your thoughts as you read
Directions: As you read, please complete the chart below describing why we should be concerned about
drugs in our water, how drugs get into our water, and possible solutions to the problem of drugs in our
water. Use bullets for each new idea.
Questions
Provide at least two answers for each question.
Use bullets or numbers.
Why should we care
about drugs in our
water?
How do drugs get into
our water?
How can we remove
drugs from our water?
How can we prevent
drugs from getting into
our water in the first
place?
Answer these questions in your own words, on your own paper.
1. How does the concentration of pharmaceuticals detected in U.S. drinking water compare to the
therapeutic dose of any of the pharmaceuticals?
2. What are some examples of how pharmaceuticals dissolved in freshwater have affected fish?
3. What happens to the active ingredients in a drug when you take it?
4. Describe the path wastewater takes when it leaves your home, to when drinking water enters your
home again.
5. What did stream testing in 1999 and 2000 in the U.S. reveal?
6. What are some drawbacks to using chlorine to disinfect wastewater?
7. What are some of the methods scientists are working on to remove pharmaceuticals from drinking
water?
8. What are some pros and cons of using ozone as a water disinfectant?
9. Describe the guidelines for disposing of unused medications.
Sewage: The Hottest New Resource?
1. What are the different sources or constituents of wastewater (sewage) that leave a home?
The sources or constituents of sewage include human waste, food, grease, soaps, water from sinks,
showers, bathtubs, toilets, washing machines and dishwashers.
2. What are the four stages of wastewater treatment?
The four stages of treatment are:
a. physical treatment,
b. biological treatment,
c. filtration and
d. disinfection
3. What three properties of waste material in sewage allow for separation in the physical
treatment stage?
The three properties of waste material that allow for separation include size of particles, solubility of
various constituents, and the density of the waste material.
4. What are the three steps used by bacteria to convert nitrogen-containing compounds into free
nitrogen gas (N2) that escapes into the atmosphere?
Different types of bacteria first convert the compound ammonia (NH3) into the nitrite ion, NO2 by
reacting with oxygen. The nitrite ion is changed into the nitrate ion, NO3 again by reacting with
oxygen. Finally, the nitrate ion is converted to nitrogen gas by reacting with an organic (carboncontaining) molecule.
5. What uses are made of non-potable wastewater that has undergone final treatment?
The wastewater can be used for non-drinking purposes such as irrigation, parks and roof gardens,
boat-washing and cleaning tasks in the treatment plant itself.
6. How is non-potable wastewater used to generate electricity?
In Santa Rosa California, treated wastewater is pumped up into the mountains where it is injected
into mile-deep cracks in the earth, re-supplying dried-up geysers. Here the water is heated to boiling
by the underground rocks producing steam that can be used to turn generators for electricity
production.
7. What is reverse osmosis as used in the treatment of disinfected effluent?
Reverse osmosis is a process in which water containing viruses and ions of common salts is forced
by pressure to pass through a very fine membrane against a concentration gradient.
8. What is removed from disinfected effluent using reverse osmosis?
Reverse osmosis is used to remove various dissolved inorganic salts.
9. What is meant by “recharging” through the use of sanitized (disinfected) effluent water?
Recharging involves using perfectly drinkable water from treated effluent to either percolate down
through soil that acts as an additional filter or is added to large bodies of water.
10. What is one of the drawbacks in using chlorine as a disinfectant for wastewater treatment?
Chlorine can react with organic matter (carbon-containing molecules) to form cancer-causing
molecules called trihalomethanes.
Drugs Down the Drain: The Drugs You Swallow, the Water You Drink
1. How does the concentration of pharmaceuticals detected in U.S. drinking water compare to
the therapeutic dose of any of the pharmaceuticals?
The highest concentration of any pharmaceutical detected in U.S. drinking water was approximately
5 million times lower than the therapeutic dose.
2. What are some examples of how pharmaceuticals dissolved in freshwater have affected fish?
Studies have revealed traces of common pharmaceuticals in the brains, livers, and muscles of
freshwater fish. In another study, fish exposed to synthetic female hormones from birth-control pills
developed both male and female reproductive organs. Another study showed that minnows exposed
to antidepressants lost their instinct to avoid predators.
3. What happens to the active ingredients in a drug when you take it?
When you take a drug, your body uses only a portion of the active ingredients. The rest is excreted
and is released into the sewer system when you flush the toilet.
4. Describe the path wastewater takes when it leaves your home, to when drinking water enters
your home again.
Wastewater travels through underground pipes to a sewage treatment plant, where it is treated to
remove harmful bacteria and toxins. Liquid discharge from sewage treatment plants is released into
rivers, lakes, and reservoirs, where the water eventually is taken up by water treatment plants. The
water treatment plants treat water to remove bacteria and other contaminants and produce potable
water that is piped to your home.
5. What did stream testing in 1999 and 2000 in the U.S. reveal?
Water sampling revealed that 80% of the waterways tested contained detectable levels of
pharmaceuticals, insecticides, and fire retardants.
6. What are some drawbacks to using chlorine to disinfect wastewater?
While chlorine completely removes some drugs present in water, others escape chlorine treatment.
Another drawback is that chlorine can react with pharmaceuticals and personal-care products to form
more toxic compounds.
7. What are some of the methods scientists are working on to remove pharmaceuticals from
drinking water?
Some potential solutions are adjusting the pH of water being treated to improve the effectiveness of
chlorine disinfection, the use of activated charcoal filters, ozone treatment, cultivating bacteria to
gobble up drugs, and educating consumers on proper disposal.
8. What are some pros and cons of using ozone as a water disinfectant?
Pros include: Ozone is a more potent disinfectant than chlorine, works over a wide range of
temperature and pH levels, and leaves no chemical residue in treated water. Cons include: A lack of
a residual effect leaves water susceptible to contamination after treatment and its high energy cost.
9. Describe the guidelines for disposing of unused medications.
Never flush or pour drugs down the drain unless the accompanying patient instructions advise you to.
If no take-back drug programs are available locally, remove drugs from their containers, crush, and
mix with an unappetizing substance, then seal in a plastic bag, and throw in the garbage.