SCIENCE AND TECHNOLOGY: WELL DONE
ACTIVITY DESCRIPTION:
Using a model this activity shows how easily a
well can become contaminated and then
spread the contamination to different wells and
to the water that would be extracted for human
consumption. This activity teaches students
that aquifers are connected underground and
therefore if one well becomes contaminated, it
MATERIALS
Hand pump
Two plexiglass tubes connected by
flexible tubing, half filled with rocks
Bucket/jug to hold drainage water
Make sure you have all items
before the students arrive!
is easy to contaminate the entire aquifer and
the water that sources other wells.
York Children’s Water Festival: Activity Descriptions
Before you start make sure the aquifer model is set up properly according to the
picture. Make sure both aquifers are full with water to the top of the rocks.
Does everybody know where the water that they use in their homes, to drink, cook
and clean with, comes from? The water supply in York Region depends on where you
live. Georgina receives its water from Lake Simcoe and municipal wells. East
Gwillimbury and King get their water from groundwater sources and municipal wells.
Newmarket, Aurora, Whitchurch-Stouffville, and Vaughan receive their water from
Lake Ontario, groundwater sources, and wells. Richmond Hill and Markham receive
their water from Lake Ontario and wells.
How do people get water from the ground? They use a well. A well is an opening that is
drilled into an aquifer. An aquifer is a layer of sand, gravel, or bedrock through which
groundwater flows. If you would like to get more specific, the well will drill into the
saturated zone of the aquifer. An easy way to think of an aquifer and the saturation zone is
to picture a piece of Swiss cheese laying flat. Does anyone know what Swiss cheese looks
like? Wait for Answers. The actual cheese is the aquifer. However, instead of being made
of cheese it is made of sand, gravel and bedrock. Now pretend the holes in the Swiss
cheese are filled with water. These water filled holes are the saturation zone. Now if there
were no holes in an aquifer, then water would not be able to get through. Therefore it is
important that the aquifer is made up of permeable materials so that the water can pass
through.
The tricky thing to remember about aquifers is that they are all connected. They don’t stop
and start. An aquifer is a horizontal layer that goes on forever underneath the earth’s
surface. The only thing that changes about an aquifer are the materials that makes it up.
Some aquifers might have a lot of gravel while another aquifer may be composed mainly of
sand. Since aquifers are all connected underground, if we pollute the water in one well or
one area, it will easily spread underground to contaminate all the water within that aquifer.
When a well is drilled into the aquifer it creates a way for the water to reach the surface.
The water reaches the surface by the pump creating suction. Think of when you are
drinking a cup of water with a straw. You create suction by sucking on the straw, water
travels up the straw and you get a refreshing drink. A well works the same way.
York Children’s Water Festival: Activity Descriptions
SCIENCE AND TECHNOLOGY: WELL DONE
BEGIN THE ACTIVITY
represent two different wells that have been drilled in the same aquifer. The tube on your
left represents a drinking water well that has been drilled above a farmer’s field and
supplies drinking water for all of Bruce’s Mill. The tube on your right is another well that is
drilled from the same aquifer.
What is a contaminant? Contaminants are things that cause pollution, or make the water
dirty and unsafe for us to drink or use. What are some examples of contaminants? Oil,
petroleum/gas, toxics such as heavy metals, or hazardous wastes (even those from the
home) that are poured on the ground outside. Also, things like bacterial contamination from
human waste and sewage, like from a septic system that is not working properly.
Let’s go back to our scenario. What happens if the farmer, who lives on the field where the
first well is drilled, wants to put chemicals, also called pesticides, on his crops to kill all the
weeds? Raise your hand if you think those chemicals will reach our drinking water and
affect the water in the other well? Raise your hand if you think our drinking water and the
water in the other well will stay nice and clean?
Use the hand pump in the left well to pump the water into a drainage bucket. Pay
attention to the water level in the right well as water is extracted from the left well. Explain
how when the water is pumped out of the left well, the water level also changes in
the right well because the wells are connected, just like they would be in an
aquifer. Therefore, if water is extracted in one well, it can easily affect water
levels in another well within the same aquifer. If water levels can be affected in
different wells just by pumping some water out of one well, then if we pollute one well, the
water in a different well can easily be contaminated also.
It is very easy for chemicals to contaminate our drinking water, especially since aquifers are
connected underground. That is why it is so important to be careful with what we are
putting into the ground. Do you think the same thing could have happened with dog poop?
Garbage juices? Oil? Absolutely! We have to remember that everything we put in the
ground has a very good chance of contaminating our water. We are lucky in Canada. We
have a lot of processes that will clean the water that comes from the well before we drink it.
However it cannot clean everything and it uses harsh chemicals to do the cleaning.
York Children’s Water Festival: Activity Descriptions
SCIENCE AND TECHNOLOGY: WELL DONE
The model display in front of you shows two points on the aquifer. These two tubes
1. Don’t use pesticides on lawns
2. Plant trees and shrubs in our neighbourhood to fight runoff
3. Conserve water so less has to be treated and less is dumped into our natural waterways
4. Now that you know, talk to your friends and family about what they can do, too!
If students would like to experience pumping a well, line them up beside the two
life size real wells and students can take turns one by one using the pump on one
of the life size well.
WHAT HAVE WE LEARNED?
Do not contaminate the water! Do not take water for granted!
Updated March 29, 2012
York Children’s Water Festival: Activity Descriptions
SCIENCE AND TECHNOLOGY: WELL DONE
What can we do?