SCI 207 UAGC Groundwater and Surface Water Interactions Lab Report

Groundwater and Surface
Water Interactions
Table of Contents
Time Requirements
Activity 1
10 Activity 2
11 Activity 3
13 Submission
13 Disposal and Cleanup
14 Lab Worksheet
Clean drinking water is vital for all human life. In this lab, students
will learn how freshwater sources interact through the natural
processes of the hydrosphere (all the water on the planet)
and what happens to drinking water supplies when our planet
becomes altered by human activities. Students will design models
of different scenarios that affect the earth’s surface water and
groundwater. The models will demonstrate overconsumption and
drought situations, along with water conditions influenced by
point and non-point source pollution, to examine human-induced
effects on the earth’s water cycle.
• Describe the importance of freshwater availability to the health of
human populations.
• Construct multiple groundwater and surface water models and
analyze different ways the water can become contaminated.
• Distinguish between point and non-point pollution sources and
explain the impact of each.
• Recognize the interconnectedness of groundwater and surface
water in the environment.
Time Requirements
Preparation …………………………………………………………… 15 minutes
Activity 1: High Withdrawal and Recharge ………………… 45 minutes
Activity 2: Point Source Pollution …………………………….. 15 minutes
Activity 3: Non-Point Source Pollution ……………………… 45 minutes
Personal protective
goggles gloves apron
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link to
photograph stopwatch
results and
warning corrosion flammable toxic environment health hazard
The hydrosphere encompasses all the water
on the planet. It includes freshwater and
saltwater; liquid, solid, and vapor; and water
that is both above ground and underground. All
of these different sources of water interact and
transform into one another through processes
within the biogeochemical cycle known as the
hydrological or water cycle (see Figure 1).
Water falls to the earth as precipitation and runs
off the land’s surface, infiltrates the ground, or
evaporates from surface waters such as oceans,
lakes, and rivers. The evaporated water vapor
condenses in the clouds and falls to the earth
over time as precipitation. Then the process
begins again. The water that has infiltrated the
ground, known as groundwater, is located
in and below the water table, which is the
top layer of the soil in which groundwater fills
most of the pores. In the water table, water is
able to enter the ground through unsaturated
surface soil voids, filling the soil below this
level due to natural gravitational pull. With this
natural movement of water, the hydrosphere
continuously cycles all phases of water to all
parts of the earth.
While water encompasses approximately 70%
of Earth’s surface, freshwater, which accounts
for only 3% of Earth’s water, is the only type
of water that is readily accessible for human
consumption. However, of that 3%, just under
1% is readily accessible, with the remaining
water being held in Earth’s icy regions, which
include glaciers and polar ice caps. This is
known as the cryosphere, or the frozen portion
of the hydrosphere (see Figure 2).
Figure 1.
continued on next page
Background continued
Figure 2.
67% Saltwater
30% Land
2% Frozen Water
1% Groundwater/Surface Water/
Freshwater available for human use is made
up of surface water and groundwater. When
precipitation falls from the atmosphere to the
earth, it becomes part of the environment by
either washing across the land and into bodies
of water or by percolating through the surface
of the soil. Here, it can be taken up by plants or
filtered deep into the ground. In the latter case,
this surface water enters the ground through
areas known as recharge zones. Water enters
these unsaturated zones on the surface of the
land by the natural pull of gravity. The porosity
of a material is a measure of the void spaces
in the rocks and soil, and the ability of water
to pass through those void spaces is known
as permeability. This water now enters the
groundwater system and saturates the ground
beneath. People rely on these zones to recharge
aquifers. Through the use of wells, people can
supply water to their homes.
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Deeper into the ground, multiple layers of
unsaturated and saturated soil of many different
pore sizes and material types exist. Some of
these layers are permeable, whereas others are
impermeable, which means that water cannot
easily pass through them. Many types of ground
consist of permeable materials, like rocky
sediment, fine sand, or soil. Others are made
of less permeable materials that impede the
percolation of water, such as claylike dirt, thicker
sand, or man-made structures such as paved
streets and sidewalks. The types of material that
make up the consistency of the ground impacts
the ability to access the groundwater.
Groundwater can sometimes be accessed by
pumping wells placed in aquifers. Aquifers are
underground basins from which water can be
removed at a reasonable rate, with the most
ideal aquifers containing many pore spaces
for water storage. However, the size, depth,
and amount of water within an aquifer can
vary greatly, making the process of extracting
groundwater from an aquifer variable as well.
While most of Earth’s accessible freshwater is
held in the ground, much of it is too deep for
humans to access.
Surface Water
The small amount of remaining freshwater
accessible for human use is made up of all the
surface water from lakes, rivers, and ponds
as well as the water vapor in the atmosphere
(see Figure 2). There are many regions that
don’t have access to groundwater sources
and must rely on reservoirs, such as natural
and man-made lakes, as a source of drinking
water. With surface water making up a small
continued on next page
percentage of freshwater worldwide, events
such as droughts or excessive withdrawal from
reservoirs within these areas can cause rapid
depletion of vital water for highly populated,
metropolitan areas that rely on these sources
of drinking water. Also, many human-induced
factors can lead to inaccessible freshwater.
Impervious surfaces such as roads, parking
lots, and buildings can limit the quality of
accessible water by creating a surface for the
runoff of pollutants into nearby bodies of water.
Additionally, most water that is withdrawn
from a waterway or aquifer is returned to the
environment, but some is taken up by plants and
animals or lost to evaporation, adding another
source of inaccessible freshwater for humans.
To understand how surface water and
groundwater affect each other, let’s investigate
some of these same scenarios but from a
different perspective. For instance, impervious
surfaces not only negatively affect the quality of
surface water, but they can also block access
to and pollute groundwater sources. Also,
when excessive water is withdrawn from a
groundwater well that is pumping water stored
in the water table, surface water levels can
be reduced greatly and can ruin the quality
of the water. Similarly, pumping water from a
freshwater reservoir can lower groundwater
levels and possibly cause contamination.
On the positive side, if there is sufficient rainfall
in an environment, the water could overflow
the land, feeding into marshes, rivers, or
lakes. In contrast, if surface water receives
excess rainfall, it could run onto and infiltrate
the land to become groundwater. All in all, to
truly understand the availability of water in a
region, recognizing the interconnectedness
of groundwater and surface water is of vital
Human-Induced Actions that Affect the
Water Cycle
There are many ways to limit or contaminate the
freshwater available to humans. The overload of
substances that are harmful to the environment,
known as pollution, is a major issue affecting
today’s freshwater supply. It is easier to
determine the origin of certain pollutants than
others; in turn, it is easier to prevent certain
pollutants from occurring in the future than
others. Point source pollution is pollution that
can be tracked to one specific source. This
source of pollution is identifiable and able to
be limited if proper action is taken to control
the pollutant source. A pipe from a wastewater
treatment plant discharging waste into a water
source (see Figure 3) and a person dumping
gasoline into a water supply (such as a lake)
Figure 3.
continued on next page
Background continued
are examples of point source pollution. Many
restrictions have been put in place to control
waste from industries and wastewater treatment
plants, but enforcing them is not an easy task.
If the origin of a pollutant is unknown, it may
be difficult to determine how it entered the
freshwater supply. Non-point source pollution
usually occurs from the movement of pollutants
through a system to a different area, making its
origins much harder to discover. When water
moves toxic chemicals—such as fertilizers and
pesticides, oil, and gasolines—over the ground
or through an aquatic system such as a river or
stream, the pollutants can travel large distances.
Figure 4 shows an example of this movement
of polluted water over an impermeable surface
(road) into the sewer system. All these types
of pollutants can start in one region and end
up many miles
Figure 4.
away, making this
type of pollution
very difficult to
prevent. Non-point
source pollution
is also the most
prevalent type in
the environment,
making it extremely
important to
While pollution is
a big part of what
limits our available
resources, there
are also issues with
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and overconsumption from aquifers and
reservoirs. With very few limits set on water
usage in most developed countries, people
worldwide use water at a rate that is faster than
it is able to be replenished in the environment.
Although water is recycled through precipitation,
evaporation, and runoff in the water cycle, there
is a need for limits on water usage to ensure
that sufficient water supplies are accessible. In a
model known as the water budget, the inputs,
outputs, and storage of water in the environment
are calculated and balanced to ensure equal
However, with droughts and excessive
withdrawals occurring in many areas around
the world, water usage must be monitored and
lowered to keep the budget balanced. In the
United States, each person uses an average
of 150 gallons of water per day; in multiple
developing countries, the average person uses
fewer than 10 gallons of water per day. Of
the large amount of water that is used by the
United States, only 13% is used by households.
The other 87% is used by industry and for
agriculture. Even though there is only a small
percentage of freshwater readily available
for human consumption around the world, it
is still being used at a rate that can lead to
dangerously low levels in the near future.
Through the following activities, you will create
groundwater and surface water models to
demonstrate the impact of several important
factors on drinking water.
Needed from the equipment kit:
Needed from the materials kit:
Clay, ¼-pound
blue bar
Sand, 4 cups
Gravel, 2 cups
Plastic cup
Permanent marker
Needed but not supplied:
• Water
• Stopwatch (or a cell
• Tape
phone with a timer)
• Plastic bowl/container • Camera (or cell phone
• Scissors
capable of taking
• Paper towels
container, 64
drink mix
2 Pieces
2 Plastic tubes
3 Straws
Syringe, 10 mL
Important: Items will be reused. Do not
throw anything away between activities.
You will rinse items such as sand and gravel
over a plastic bowl/container placed in the
sink to separate the materials from each
other; the bowl will prevent any excess
materials from clogging the sink. You will
rinse the syringe and aquarium tubing
between activities and reuse them. You will
also use the clay and Kool-Aid® drink mix for
multiple activities, so be sure to save these
Reorder Information: Replacement supplies
for the Groundwater and Surface Water
Interactions investigation can be ordered
from Carolina Biological Supply Company,
item number 580817.
Foam cup
Call: 800.334.5551 to order.
Wear your safety
goggles, gloves, and
lab apron for the duration of this investigation.
Read all instructions for these laboratory activities before beginning. Follow the instructions
closely, and observe established laboratory
safety practices, including the use of appropriate
personal protective equipment (PPE).
1. Read through the activities.
2. Obtain all materials.
3. Find a large, open table to serve as the work
area. Clean the work area.
4. Have a trash can and an accessible sink
Do not eat, drink, or chew gum while performing
these activities. Wash your hands with soap and
water before and after performing each activity.
Clean the work area with soap and water after
completing the investigation. Keep pets and
children away from lab materials and equipment.
The clay may stain your clothing and hands,
so be sure to use care and wash your hands
thoroughly after handling this item, in particular. Make sure to wear your gloves and
your lab apron when handling the clay.
continued on next page
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A High Withdrawal and Recharge
In the following activity, you will learn the
importance of the water cycle and how
withdrawal and recharge are two processes
that continuously affect the environment
but are not always in a balanced state. You
will create a model where a drinking water
reservoir and a layer of land with groundwater wells within it will be separated from
each other by an impermeable layer. To help
better understand the interconnectedness
of the two water systems, you will determine
different rates of withdrawal and recharge.
How do you think the removal of water from
the well will affect the water in the reservoir?
Propose a hypothesis stating whether you think
the water level in the reservoir will rise, drop, or
remain the same, and describe your reasoning.
Complete this information in the “Hypotheses”
section of the Lab Worksheet.
Figure 5.
1. Place a block of clay in
the plastic container so
it is one-third of the total
distance away from one
side of the container. This
piece of clay will act as
an impermeable retaining
rock, so make sure to
mold the clay so that it
fits tightly on the sides
and on the bottom of the
container. If you find the
block of clay difficult to mold, heat it in a
microwave on high power for 7 seconds, and
it will become much more pliable.
2. The smaller section will represent the
reservoir and the larger section will be the
aquifer, as seen in Figure 5.
3. Take one of the clear plastic tubes (not to
be confused with the aquarium tubing), and
cut it in half with a pair of scissors. These
two cylinders will model wells drilled into the
ground to reach the aquifer.
4. Add just enough sand to cover the bottom of
the aquifer section, spreading the sand with
your hands to level it out.
5. Place the two cut plastic tube pieces (wells)
upright in the sand near the edge of the
container in the aquifer farthest from the clay
bar at random areas (see Figure 5). Ensure
that each well is seated firmly against the
bottom of the container.
6. Add another layer of sand, making sure to
have the sand slightly higher up on one well
than the other.
7. Form the next layer of the aquifer by adding
enough gravel to cover the sand while creating a slight
Figure 6a.
incline. Form
the top of the
incline around
the wells. The
gravel hill should
slope downward toward
the retaining
Figure 6b.
wall (clay) and
should be even
with the top of
the clay (see
Figure 6a and
continued on next page
ACTIVITY 1 continued
8. To represent precipitation, poke
approximately 10 holes in the bottom of
the foam cup and fill it with water (over the
model), allowing the water to sprinkle onto
the top of the slope, near the edge of the
container behind the wells. Some water may
leak into the reservoir.
9. Fill the smaller section (the reservoir) with
water until the water level rises a few
centimeters over the clay retaining wall.
10. The top of the water table is represented by
the height of the water in each of the wells.
11. Insert a straw into one of the wells until it
touches the bottom. Hold your forefinger
tightly over the open end of the straw to
create a seal, and then remove the straw
from the well. Use the permanent marker to
draw a line to mark the top of the water level
in the straw. This line represents the top of
the water level in the aquifer.
12. Using a disposable pipet, drain this well by
squeezing the round bulb of the pipet before
putting it into the water, putting the pipet
tip down into the water, and releasing the
bulb to suck up the water. This water can be
placed in a cup for disposal. Use the pipet to
empty all the water in this well. (There may
be a mixture of sand and water removed.)
13. As soon as you have removed all the water
in the well, place the straw back into the
bottom of the well and remove a water
sample as you did in Step 11. Mark the
top of the water column with a permanent
marker as before. This represents the level
of water in the well after a period of high
withdrawal. Record your observations
in the “Observations” section of the Lab
Wait 2 minutes and observe
what happens to the drained
well. Measure the water level again using
the straw and the permanent marker, and
note if the height of the water table has
changed in the “Observations” section of
the Lab Worksheet. Has the height of the
water table decreased or increased? Take
a photograph, zooming in on the markings
on your straw to show how much this
water level has changed. Include in your
photograph a strip of paper with your name
and the date clearly written on it. You will be
uploading this photograph to your lab report.
15. If needed, refill the reservoir with water until
the water level rises a few centimeters over
the retaining wall (as in Step 9).
16. Repeat Steps 11–14 using the other well.
A Point Source Pollution
For this activity, you will create a model of
point source pollution: a large industrial plant
is disposing of its waste materials through
a discharge pipe into a drinking water
reservoir. You will see how these pollutants
play a role within the water cycle and if an
impermeable layer has an effect in blocking
contamination of the groundwater.
Do you think that the polluted water from the
reservoir will enter the groundwater supply?
Propose a hypothesis stating what you think will
continued on next page
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happen, and describe your reasoning. Complete
this information in the “Hypotheses” section of
the Lab Worksheet.
1. If the water from the reservoir in Activity 1
has a large amount of sand in it, pour it into a
bowl and remove any excess sand from the
reservoir. Do your best to let only water drain
from the aquifer section, keeping all other
materials (clay, sand, gravel, and tubes) in
tubing (discharge pipe) you created (see
Figure 7).
8. Observe and record what happens to the
water in the reservoir as you pump the waste
into the discharge pipe in the “Observations”
section of the Lab Worksheet.
2. Take one of the thinner, flexible aquarium
tubes and cut it in half. This will act as a
discharge pipe from an industrial plant.
9. Next, insert a straw into one of the wells until
it touches the bottom. Hold your forefinger
tightly over the open end of the straw to
create a seal, and then remove the straw from
the well (as in Activity 1) to see if the polluted
water has made its way into the groundwater
3. Tape the aquarium tube half to the inside of
the plastic container in the reservoir, making
sure the opening is not touching the bottom
of the container.
To verify, wait 1 minute and repeat
Step 9; then wait another minute and
repeat the step again.
Take a photograph of your model with
your straw in the picture to show
if there is any pollution occurring in the
groundwater supply. Include in your
photograph a strip of paper with your name
and the date clearly written on it. You will be
uploading this photograph to your lab report.
4. Fill the reservoir with clean water until it is just
above the top of the clay.
5. Take a cupful of water and pour a small
amount of Kool-Aid® drink mix into it (just
enough for the water to change color). Mix
well. This will represent the waste (pollutant).
6. Use the 10-mL syringe to suck up the waste.
7. Attach the end of the syringe to the aquarium
tube, and inject the waste into the aquarium
Figure 7.
12. After you have completed this activity,
obtain a medium- to large-size plastic
bowl/container. Take a handful of the gravel
and sand mixture. Rinse water through it,
separating the gravel (in your hand) from
the sand and water mixture (now in the
bowl). Place the gravel on a paper towel to
the side; let the excess water drain into the
bowl, either in the sink or outside on the
ground, being careful to retain as much sand
as possible in the bowl. Reuse the sand and
gravel for Activity 3. If weather permits, this
step can be done outside for easier cleanup.
A Non-Point Source Pollution
In this activity, you will see the effects on
drinking water in two locations:
• a house on a hill, where drinking water
comes from a well confined under an
impermeable layer
• a house located downhill by a pond,
where drinking water comes from a well
in a permeable layer
All the land between the two houses is
fertilized each year, and both homeowners
want to know the effects that this potential
pollutant (fertilizer) has on their water source
in the event of runoff from a rain event.
Hypothesize how adding fertilizer to this new
model will affect the other components of
the model. Describe your reasoning. In your
hypothesis, you should consider the following:
1) the groundwater, 2) the pond water, and
Figure 8.
Figure 9.
3) the drinking water reservoir. Complete this
information in the “Hypotheses” section of the
Lab Worksheet.
1. Take the bar of clay from the previous activity,
and flatten it out as much as possible, making
an approximate 6 × 6 cm square.
2. Cut the remaining aquarium tube in half,
taping one piece to the inside (on a short side)
of the plastic container, midway down. Tape
the other half of the aquarium tube opposite
the previous one and at the same depth in the
plastic container. These tubes represent wells
(see Figure 8).
3. Choose one side of the container, and fill it
with sand to a depth slightly higher than the
bottom of the well, as shown in Figure 9.
4. On the other side, make a slope of sand a few
centimeters higher as you continue placing
sand throughout the container. Supplement
this layer with a layer of gravel on top,
continuing the sloped approach (see
Figure 10.
continued on next page
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Figure 11.
Figure 12.
5. Place the flattened piece of clay on top of the
uphill side, and mold the clay so that it fits
tightly around the well (see Figure 11). This
will act as an impermeable layer.
6. Top the model with a thin layer of sand,
continuing with the sloped approach.
7. In the sand/gravel mixture at the bottom
of the hill, dig a small circular hole. Using
a plastic cup from the equipment set, pour
water into the hole to represent a pond (see
Figure 12).
8. Take the opened Kool-Aid® drink mix packet
and sprinkle the remaining contents along the
surface of the sloped land. This will act as
fertilizer on the landscape.
9. Put water (without Kool-Aid® drink mix) in
the foam cup, and shake the cup along the
land to simulate rain. Observe what happens
to the fertilizer and how it affects both the
groundwater and pond water (by tracking
the now-colored water), and record your
observations in the “Observations” section of
the Lab Worksheet.
Wait 30 seconds, and then
use the 10-mL syringe to
pump water out of the well that is not
surrounded by the impermeable clay layer.
Observe the color of the water that came
out of the well along with
the pond water color. (Some
sediment may be sucked into
the syringe during this step.)
Record your observations in
the “Observations” section
of the Lab Worksheet. Take
a photograph of your model
with the syringe in the picture
to show the color of the water.
Include in your photograph a
strip of paper with your name and the date
clearly written on it. You will be uploading
this photograph to your lab report.
11. Now use the syringe to draw water from
the uphill well that is confined by an
impermeable layer. Observe the color of
the water that came from this well. (Some
sediment may be sucked into the syringe
during this step). Record your observations
in the “Observations” section of the Lab
Using the Lab Report Template provided,
submit your completed report to Waypoint for
grading. It is not necessary to turn in the Lab
Disposal and Cleanup
1. Rinse and dry the lab equipment from the
equipment kit, and return the materials to
your equipment kit.
2. Dispose of any materials from the materials
kit in the household trash. The plastic
container may be recyclable.
3. Sanitize the work space, and wash your
hands thoroughly.
Lab Worksheet
Activity 1.
Activity 2.
Activity 3.
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Activity 1.
Activity 2.
Activity 3.
Groundwater and Surface Water Interactions
Investigation Manual
Carolina Biological Supply Company • 800.334.5551
©2019 Carolina Biological Supply Company
CB781621908 ASH_V2.2
Name of Lab
Your Name
SCI 207: Our Dependence Upon the Environment
Instructor’s Name
*Use this template to write your lab report each week. Complete the sections below, pasting in
all completed data tables, graphs, and photographs where indicated. Before you submit your
report, run it through Turnitin using the student folder to safeguard against accidental plagiarism.
Please delete this text along with all other template instructions before submitting your report.
Title of Lab Goes Here
Explain the lab topic background (not the lab itself), including the most important terms and
concepts that are covered in it. Why is the subject of this lab important? Use at least one credible
source other than the lab manual or textbook to write this section; cite the source(s) using APA
format. Your background paragraph should be at least 5-7 sentences, not including any quoted
In a separate paragraph, state your hypotheses one at a time, in the order of the activities in the
lab. Provide at least one hypothesis for each lab activity. For each hypothesis, explain your
reasoning behind what you thought would happen. You should have written your hypotheses
before you conducted your experiments. Do not provide any results from the lab here – the
results go later in your report (see below).
Data Tables and Observations
Copy and paste completed data tables here, in order. Make sure that each table is clearly labeled.
There should be data tables for all lab reports except Weeks Three and Four. For Week Three,
provide your observations from the lab here. For Week Four, there this section will be blank.
Graphs and Photographs
Paste your graphs here (Weeks One and Four only). Paste your photographs here (Weeks Two,
Three, and Five only), in the order they were taken during the lab. Provide captions for each
graph or photograph. Remember that all photos for the labs in Weeks Two, Three, and Five must
include a strip of paper with your name and the date clearly written on it. Lab reports without
photos will be returned ungraded. For the virtual labs (Weeks One and Four only), at least one
graph must be included in this section for the lab report to be evaluated.
Based upon the results of each lab activity, explain whether you accepted or rejected each of
your hypotheses, and why.
In one or more well-written paragraphs: 1) Restate your original hypothesis for the lab activity;
2) Communicate the results of the lab, referring back to specific results from your data tables,
photos, graphs, or observations; 3) Compare your hypothesis to your results and decide either to
accept your hypothesis or to reject it; 4) State whether you accept your hypothesis or reject it and
explain with evidence; 5) Move on to the next hypothesis and repeat these steps.
Reminder: this section should be written in paragraph form, not as bulleted or numbered lists.
In your own words, how do the results of this lab relate to the scientific literature and/or to realworld applications? Using a source other than the lab manual or textbook, provide supporting
facts or concepts that help you make meaning of the lab results. Cite the source using APA
format. Your answer should be at least 5-7 substantive sentences in length, not including any
quoted material.
In a separate paragraph, what challenges and/or possible mistakes did you experience when
completing this lab? Identify at least one. How might those challenges and/or. mistakes have
impacted the accuracy of your results?
List the references that you cited in your report, in APA format and alphabetically by author’s
last name. If you did not cite the source somewhere in your paper, do not include it.
Lab Worksheet
Activity 1.
Activity 2.
Activity 3.
Activity 1.
Activity 2.
Activity 3.

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