Little Drip
•GROUNDWATER
1)
As you watch this power point, look for the vocabulary in gold. Write the words
and definitions in your science notebook.
2)
There are questions asked by Big Earth, and these are in green and numbered
Be sure to look carefully at these questions and try to answer them.
3)
Have fun and learn a lot!
This slide presentation has two parts:
Part One: Explain how water exists below the Earth’s surface and how it is
replenished. (Benchmark 3).
Slides 1-25
Part Two: Describe the origins of pollution in the hydrosphere.
Slides 26-39.
(Benchmark 4)
“Hey Big Earth, I’ve been thinking. I’m on my
way down to this big body of water but what
are my choices. Do I have any other places I
could go?”
“Sure Little Drip, you have lots of choices. Some of
them, like this ocean, are salt water. Other salt water
bodies include some bays, seas and of course all the
oceans.”
“What if I don’t like salt water. Do I
have any other options?.”
“Well there is always freshwater such as most lakes (a
large body of water surrounded by land), rivers (a
natural stream of water of considerable volume), and
groundwater. These are called freshwater because
they don’t have the salt content like the oceans.”
“Here is a list of percentages of where the water is
actually located in what is called our hydrosphere.
The hydrosphere is ALL the Earth’s liquid water.
Freshwater is what human’s need to live you know.
They need it to drink and for many other of their
everyday activities”.
EARTH'S WATER SUPPLY
(1) Can you tell me,
Little Drip, which of
these forms of water
is usable by humans?
Oceans
Ice
Groundwater
Soil Moisture
Atmosphere
Inland Lakes
Rivers
97.3%
2.19%
0.5%
0.005%
0.001%
0.018%
0.000096%
“Hmm, let me see. Wow! It looks only like a very
small percent.”
“You are
right. Most
of the
water,
99.7% is
unusable by
humans.
Less than 1% is for
human use. That is
why it is so
important for
everyone to take
good care of our
water.
“After looking at that graph, I see most of the
freshwater is called groundwater. What is the
difference between freshwater ( lakes, rivers,
streams) and groundwater? Or are they the same as
groundwater?”
“Surface water is like the water we are over. It is exactly
how it sounds: water found on the surface like lakes, rivers
and streams.
Groundwater is the water in the ground. Here, let’s watch
this video to learn a little bit about groundwater. Just click
on the picture below, and Little Drip, be patient. A four
minute video will start that will give you some more
information just about groundwater and how important it is.
We can then talk about it some more once you understand the
basics.”
http://www.leapingmedia.com/groundwater.html
“Wow, that
was way cool!
But I need to
go slower so I
can really
understand all
the details.
Can you walk
me through it
step by step?”
“Sure, first you
saw that
groundwater is
just that,
water under the
ground. But
how does it get
there?”
“Hmm, it must come from
clouds just like I do.”
“Well, that’s part of the story.
Groundwater comes from rain or snow seeping into
the ground. Seep is a slow movement of water
through the cracks and pores in the soil.
Groundwater also comes from water deep within the ground.
Lakes and rivers feed groundwater.
But groundwater also feeds lakes and rivers.”
“Look at this picture.
Here you can see that the rock and gravel beneath the soil
is very porous. If is full of holes in or between the rocks
that can hold air or water just like a sponge. “
“If the sponge was totally filled with water so that
water would start to drip out, we would say that the
sponge was saturated. So if the rocks in the ground
are totally filled with water, then we say they are
saturated.”
“You can see in this picture the saturated soil. Here,
Little Drip, let me ask you a few questions about this
picture to see if you really understand it. Answer
them and then we will check your answers.
2)
What color is the part of the ground that is saturated
with water?
“The ground saturated with water is purple. That means
everything purple has water in all the pores or fractures.”
3) What is the very top of the saturated soil called?
“The very top of the saturated zone is called the water table.
Below this, the ground is totally filled with water or saturated.
Hey, just like a table is the top.”
4) What do you notice about the water table and the surface
water?”
“Now for the last question. That’s a toughie. It looks like
the surface water is as high as the water table.”
“Once
again, excellent Little Drip.
But let me explain surface water and the water table a bit
more.
When you see surface water you are seeing the top of the
water table. Like when you are at the beach very near the
water and you dig a hole in the sand. It doesn’t take long to
see water below because you are digging to the water table
and, below that the sand is saturated with water.”
“Yeah, but you said that the water
moves in the pores of the rocks.
How come sometimes I can’t get down
between the pores?”
“Let’s see, how can I explain
this one. O.K. There are two
different concepts here that
we need to discuss: one is
porosity and the other
permeability. Later, we will go
to the lab and do some
activities with these concepts.
But for now read on.”
“O.K. Lets see. From what I read, rocks that are
more porous have more spaces and so they can hold
more water.
Clay is made of very small pieces.
Each piece is surrounded by pore
space. Therefore, clay has a lot
of pore spaces, and clay can hold
a lot of water.
Gravel is made of bigger pieces.
Although the pore space looks
like a lot, there is a lot less of
it compared to the spaces
around the clay. It holds less
water than the clay.
“Very good Little Drip. But how about permeability?”
“O.K., now let me think a minute. Permeability is how
the pores are connected - sort of like a maze. Some
mazes are easy to find your way through while others
are more difficult because of all the obstacles.
Gravel
Fine Sand
Clay
5. Look at the water that has seeped through the gravel,
sand and clay. Which one has more water passing through?
Gravel
Fine Sand
Clay
Wow you are right on top of things. Yes, the gravel did let more
water pass through. Its pores are connected in such a way that
water moves through easily. We say gravel is permeable.
The clay made it difficult for the water to pass through. Clay has
a lot of pore space but it is much smaller spaces. Like squeezing
through a small tight hallway. We call it impermeable.
“One last thing Little Drip. Before you can be an
expert on groundwater, you need to know four
more words.”
“My brain hurts but bring them on!”
“Here we go with number one:
spring… “
“I know, something that is bouncy – hehehe!”
“No silly, a spring is when the
groundwater flows naturally
out from the ground. Once
this water reaches the
surface it looks like a small
stream flowing out of the
Earth.”
“Sometimes it looks like a pool or small lake like this one
in Michigan.”
Kitch-iti-kipi,
Upper Penninsula,
Michigan
“Here’s word number two:
aquifer.
An aquifer is an underground
formation of permeable rock or
soil.
Remember, permeable rock lets
water flow through it quite easily.
So aquifers not only hold water
but they can transmit the water
to streams, springs or even wells.
This one in Michigan is made of
sandstone.
http://capp.water.usgs.gov/aquiferBasics/images/map_marshall.gif
Have you ever had Perrier – Nestles –
or Ice Mountain bottled water?
Well, they pump 105 million gallons of
water from this aquifer every year.
#6 Little Drip, look back at the last
slide. Is this aquifer located below
Macomb County?”
No, it is Northwest of
Macomb County.
“Wow, what are the last two words?”
“Here’s a picture of an
artesian well in the
Upper Peninsula of
Michigan. The water is
coming from an aquifer
that is underground.
The water isn’t being
pumped out. It is coming
out because of the
pressure of the
underground rocks (clay
or shale).
And last, but not least: aquitard.
“An aquitard is also
underground. It is
impermeable rock that
is saturated with
water.
However, it does not
provide much water to
a well or spring.
•Here is a great website to help you learn more about these
topics. Visit this site at home to help you understand
water.
http://ga.water.usgs.gov/edu/mearth.html
Thanks so much Big Earth. I have learned so much
about water. You were a great teacher. I hope
everyone does their part to keep me clean!
“Hmm, Big Earth, I have been thinking about all this
groundwater. In the short video that I watched it said
that, ‘Waste and Pollution keep me from my task’. What
did they mean by “waste and pollution”?
“Oh Little Drip, that is such a big question. Remember it
said not to abuse groundwater. Well, you are polluted
everyday, some intentionally and some unintentionally.”
“Look at this picture of how you can look when a river or
stream is polluted.”
“Yuck, that is disgusting. Who would do
that?”
“Little Drip, it isn’t always intentionally but
sometimes it is. Think about how some families
pollute you. #7 Make a list of at least 10 things
that you think humans do everyday that get into
your groundwater system and cause pollution.”
“How did you do on your list?”
“Wow, I came up with quite a few.”
“Well, there are many sources of pollution. By sources of
pollution we mean where the pollution initially or first enters
the hydrosphere. Here are a few that we can talk about.
1. Household dumping
2. Agricultural run-off
3. Industrial waste”
“Most pollution on my list came from what businesses do,
not those people who live in houses. What kind of
pollution do they cause?”
“The number one threat to clean water today comes from
non-point source pollution. That's when rain carries
pollutants into the water. The same water where we drink,
swim or fish.
Where do these contaminants come from?
From cleaners people use around the
house, paint in old paint cans, fertilizers
they use on the lawn, litter they drop in
the street, batteries thrown in the
garbage, even detergents they use to
wash their cars. All that is known as
household dumping.”
“Some of this is put into the street sewers and called
sewage. Sewage is any liquid or solid waste carried off
in sewers or drains.”
This makes me so sad! Why would people do something
like this?
“Then Little Drip, there is agricultural run-off. Run-off is
precipitation that has fallen and is running over the ground
into our streams and rivers.
Pesticides used to control insects, fertilizers from crop fields,
as well as animal wastes from feedlots are often carried in
run-off. These are all causes of pollution.”
“Can you see how animal and crop farms add to the pollution
problem?”
“And the third major source of pollution is from industry.
Any product that people own or anything that makes their life
easier is made from what we call industry.
But the production of all these things has a downfall too.”
“Let me guess. When
factories produce all these
items, there are waste
products from them that
pollute the water. These
are called industrial waste
pollutants.
Gee, I can see that from
the picture.”
“Here are some of the most common things in each area
that cause water pollution:”
-deicing salts
-landfill trash
-house and garden chemicals
-battery acids
-car oil and gasoline
-boat oil and gasoline
-animal wastes
-fertilizer
-pesticides
-herbicides
-sewage
Industry
-underground storage tanks
-chemical spills/dumps
-thermal, heat, pollution
-pipelines
-transfer and transport spills
“This is scary. What can people do to continue to use me but
keep me clean so I can be used for drinking water and other
things?”
“Well first of all. Nature does try to clean some of its water by
natural processes. This is known as filtration. Anytime water
passes through sand, the sand acts as a filter and removes some
of the larger sewage items.
Humans even made “Waste Water Treatment Plants” to
help them try to keep you clean. However, people need
to do their part so the water doesn’t get polluted.
# 8 What do you think people
can do? Maybe we should
making a list of 10 things
that you can do to help
prevent water pollution.”
“If you need help, here’s a source
that might help you Little Drip.”
http://www.westchestergov.com/w
aterquality/checklist1.htm
Detroit’s Waste Water Treatment Plant
Well, I remember the video. The song said:
“
Protect Groundwater
Be Aware of Groundwater
Show You Care About Groundwater
People could begin with their own families by being aware of what they do
and educating their family members. Yeah, that’s a good one. If
everyone did something in their own home to stop pollution, that would
have to make a difference. If they even talked to their parents about
the problem, maybe my water would stay cleaner.
It’s a start!”
Drinking Water and Ground Water, Kids Stuff
http://www.epa.gov/safewater/kids/kids_4-8.html