Aquatics Teacher Packet
AQUATICS BENCHMARK ASSESSMENT
Teacher Answer Packet
1. Use the diagram of the water cycle below to answer the following questions.
a. How is freshwater replenished on
earth?
precipitation
b. What is the term for the underground
supply of freshwater?
aquifer
2. Refer to the pie chart below on water consumption. Identify 5 ways you can
reduce your personal water consumption.
Answers will vary
a. _Use low-flow showerheads
b. _Use low-flush toilets
c. _Take shorter showers
d. _Only run dishwasher and washing
machine
when loads are full
e. _Turn off the faucet while brushing teeth
3. Complete the table below on the salinity of water bodies.
Salinity /
Type of Water
Fresh
Brackish
Salt
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Description
Contains no salt or very little salt
Salinity ranges from 0 – 1 ppt
A mixture of salt and freshwater
Salinity ranges from 2 – 17 ppt
Water has a salt concentration
over 17 ppt
Average salinity of ocean is 35 ppt
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Example of Aquatic
Environment
River, Lake, Stream, etc.
Estuary
Ocean
Aquatics Teacher Packet
4. Complete the chart for acceptable water quality levels.
INDICATOR
ACCEPTABLE LEVEL
pH
DO
CO2
Nitrates
Phosphates
Hardness
6.5 – 8.5
5 – 8.5 ppm
< 25 ppm
<0.3 ppm
<0.015 ppm
0-60 ppm (soft), 120-180 ppm
(hard)
present
present
present
absent
Mayflies
Stoneflies
Caddisflies
Coliform
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Aquatics Teacher Packet
5. Biological and chemical water quality data were collected from 4 sites in the
Bear Creek watershed. The majority of the land in the rural Bear Creek
watershed is inhabited, but there is also a fish farm (farm where fish are raised),
a mining company, and a dairy farm. Analyze the water quality data.
WATER QUALITY DATA
Site A
Site B
Site C
Site D
Water
temp
(°C)
24
24
15
15
# of
Mayflies
# of
Stoneflies
# of
Caddisflies
pH
6
293
1571
1558
2
156
24
613
5
248
1391
1354
6.1
7.2
7.2
7.2
Hardness
(ppm)
55.0
102.0
98.5
114.0
Nitrates
(ppm)
7.0
1.7
0.25
0.25
Phosphates
(ppm)
3.2
0.5
0.0
0.01
DO
(ppm)
1.9
2.9
7.3
7.4
Coliform
Present
Absent
Absent
Absent
a. Which site has the worst water quality? Explain.
Site A has the worst water quality. The populations of macroinvertebrates are very low. The pH is
below the acceptable range, and is too acidic. Water hardness is low, indicating a lack of limestone
as a geologic substrate. Both nitrates and phosphates are elevated. Dissolved oxygen is too low for
organisms to survive. The presence of coliform indicates the body of water is contaminated with
animal waste.
b. Which site has best water quality? Explain.
Site C has the best water quality. It has the most macroinvertebrates. In addition, all chemical tests
are in the acceptable range. The absence of coliform indicates no pollution from animal waste.
c. Rank all four sites in order from best to worst water quality.
Site C  Site D  Site B  Site A
d. Describe the relationship between water temperature and the amount of dissolved oxygen.
As water temperature decreases, the amount of dissolved oxygen increases.
e. Which site is most affected by eutrophication? Explain.
Site A is most affected by eutrophication. Site A has the highest levels of nitrates and phosphates. In
addition, the low dissolved oxygen level is indicative of eutrophication.
f. Which site is most affected by acid rain? Explain.
Site A is most affected by acid rain. It has the most acidic pH and the lowest water hardness. This
indicates little limestone in the soil to buffer against the effects of acid rain.
g. Which site is contaminated with animal waste? Explain.
Site A is contaminated with animal waste. The presence of coliform bacteria indicates pollution by
animal waste.
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Aquatics Teacher Packet
6. Identify the name of the macroinvertebrate under each image.
__mayfly__
__hellgrammite___
__damselfly__
__aquatic worm__
__stonefly__
__caddisfly__
7. Several different types of stoneflies, mayflies, and caddisflies indicate healthy
water quality.
a. Rank these three indicator organisms from most tolerant of pollution to least tolerant of
pollution.
Most tolerant of pollution:
__caddisflies
__mayflies
Least tolerant of pollution:
__stoneflies
b. Which of these three indicator organism would disappear first in a polluted aquatic
ecosystem?
__stoneflies
c. What water conditions would be best for the survival of macroinvertebrates?
fast-moving stream because it oxygenates the water
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Aquatics Teacher Packet
8. Define a watershed.
Watershed:
The total land area from which water
drains into a particular water body
9. Refer to the map of the Chesapeake Bay and its major tributaries. On the map,
add a:
 Label A—River that adds the majority of the freshwater to the Bay
 Label B—Area with the highest salinity
 Label C—Area with the lowest salinity
 Label D—Area with greatest tidal changes
A
C
D
B
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Aquatics Teacher Packet
10.Label the diagram of fish with the parts of its anatomy.
Spiny dorsal fin
Soft dorsal fin
Caudal (tail) fin
Operculum (gill cover)
Mouth
Lateral line
Pectoral fin
Anal fin
Pelvic fin
11.Identify the fish below and fill in the important information about each fish.
Common Name
_______Channel Catfish____________
Body Shape: ___Torpedo________
Mouth Position: __Wide, upturned____
Caudal Fin: ____Forked_________
Dorsal Fins: _____Two (with rays)____
Pectoral Fins: __Present________
Pelvic Fins: ______Present__________
Other fins: ____Anal fin_________
Lateral line: ______Visible________
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Aquatics Teacher Packet
12.Answer the following questions about aquatic vegetation.
a. What do these terms stand for?
o SAV – Submerged Aquatic Vegetation
c. What two water factors affect the growth of SAV in the Chesapeake Bay?
Salinity and Turbidity
d. Explain how the presence of SAV would help the fish in the cartoon and other aquatic animals in
the bay
The presence of SAV is very important to the
bay. Among its many benefits, SAV provide
habitat, shelter, food, and oxygen to the bay. In
addition, SAV help maintain water quality and
protect shorelines from erosion.
e. Explain two causes that have lead to the decline of
SAV in the Chesapeake Bay
SAV has declined in the bay due to
eutrophication and sedimentation. Both of
these causes reduce the amount of sunlight
available to SAV. Over-enrichment of
nutrients causes algae blooms which prevent
sunlight from reaching SAV. Too much
sediment increases the total dissolved solids
in the bay. This also reduces the light
available for the SAV.
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Aquatics Teacher Packet
13.Using the graphic below, explain what occurs during primary, secondary, and
tertiary treatment.
Primary
WASTE WATER TREATMENT DIAGRAM
Secondary
Tertiary
Step in Wastewater
Treatment
Primary
Secondary
Tertiary/ Advanced
Explanation
Wastewater goes through screens to remove coarse debris and grit chambers.
Wastewater is then funneled into large sedimentation tanks and left undisturbed
to allow heavy particles to settle out. This sludge moves onto sludge treatment
while the remaining wastewater moves onto secondary treatment.
In an aeration tank, oxygen is added to encourage the growth of
microorganisms that consume the organic matter. Water then flows into
another sedimentation tank, where sludge settles out and moves onto sludge
treatment. The remaining wastewater goes through disinfection or chlorination
before moving onto tertiary treatment.
Many salts, pesticides, phosphates, and other pollutants remain after secondary
treatment. Tertiary treatment removes these materials and releases a treated
effluent that is theoretically “potable.”
14.Circle the best answer.
Correct answers are bolded, underlined, and italicized

Which law regulates what is discharged from a wastewater treatment plant?
(Clean Water Act, Safe Drinking Water Act)

Which law makes water potable?
(Clean Water Act, Safe Drinking Water Act)

What classification of pollution comes from a wastewater treatment plant?
(nonpoint pollution, point pollution)

What type(s) of pollution results from the process of wastewater treatment?
(acid rain, eutrophication, thermal pollution)
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Aquatics Teacher Packet
15.Use the graphic to complete both charts.
Pollution source
Point or Nonpoint
Farm
Nonpoint
Houses
Point
Factory
Point or Nonpoint
depending upon the situation
Point
Factory’s parking lot
Nonpoint
Type of pollution produced
Pollution source
Boat
Factory releases SO2 and NO
Boat releases NO
Runoff from the farm and fertilizer
on lawns
Factory pulls in water as a coolant
and releases warmer water
Acid rain
Eutrophication
Thermal pollution
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Aquatics Teacher Packet
16.Fill in the blanks.

___Nitrates__ and __phosphates__ are the two nutrients that cause eutrophication. Because of the
excess nutrients ___algae___ grows rapidly. Decomposers then move in and break down all
organic matter. This results in low levels of oxygen which can create __dead__ ___zones___.

Thermal pollution increases the ___temperature___ of the water. This change results in lower
levels of __dissolved oxygen_ in the water.

Acid rain ___lowers____ the pH of a body of water. It is primarily caused by sulfur dioxide and
nitrogen dioxide created by the burning of fossil fuels.
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Aquatics Teacher Packet
17.Below is an energy pyramid illustrating biomagnification.

Why are there more dots in the higher trophic levels?
The concentration of pollutants increases as it moves up the food chain.

Why are heavy metals such as mercury harmful?
They have high mobility, are fat soluble, and are biologically active.

In what part of an organism does the pollutant accumulate?
Fats

The organism at the highest trophic level is not killed by this pollutant; instead it can have
damaging effects on its offspring. Explain.
Biomagnification of the pollutant interferes with the reproductive system of the organism. For
example, biomagnification of DDT resulted in bald eagles laying eggs with shells that were too thin.
18.Check all that apply to each aquatic environment.
Aquatic
environment
Estuary
Wetland
Salt
water
√
Fresh
water
√
Tidal
√
Nesting
ground
√
√
√
√
√
√
Streams
Ocean
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√
Light penetrates
almost to bottom
√
√
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