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Water Information Q/A
Groundwater is an essential and vital resource
for about a quarter of all Canadians. It is their sole source of water
for drinking and washing, for farming and manufacturing, indeed, for
all their daily water needs. Yet for the majority of Canadians- those
who do not depend on it - groundwater is a hidden resource whose value
is not well understood or appreciated.
Our image of Canada is of a land of sparkling lakes rivers and
glaciers. Groundwater, which exists everywhere under the surface of the
land, is not part of this picture. Not surprisingly, therefore,
concerns of Canadians about water quality focus primarily on surface
waters- our lakes and rivers. The less visible but equally important,
groundwater resources have received less public attention, except in
regions of Canada where people depend on them.
What is groundwater?
It is sometimes thought that water flows through underground rivers or
that it collects in underground lakes. Groundwater is not confined to
only a few channels or depressions in the same way the surface water is
concentrated in streams and lakes. Rather, it exists almost everywhere
underground. It is found underground in the spaces between particles of
rock and soil, or in crevices and cracks in rock. The water filling
these opening is usually within 100 meters of the surface. Much of the
earth's fresh water is found in these spaces. At greater depths,
because of the weight of overlying rock, these openings are much
smaller, and therefore hold considerably smaller quantities of water.
Groundwater flows slowly through water-bearing formations (aquifer) at
different rates. In some places, where groundwater has dissolved
limestone to form caverns and large openings, its rate of flow can be
relatively fast but this is exceptional.
What is an aquifer?
Although groundwater exists everywhere under the ground, some parts of
the saturated zone contain more water than others. An aquifer is an
underground formation of permeable rock or loose material which can
produce useful quantities of water when trapped by a well. Aquifers
come in all sizes. They may be small, only a few hectares in area, or
very large, underlying thousands of square kilometers of the earth's
surface. They may be only a few meters thick, or they may measure
hundreds of meters from top to bottom.
How do I choose a location for my well?
The area must be relatively easy to access and should be reasonably
flat. Higher elevations are preferred to decrease the potential for
contamination that is often associated with drainage. It is also
important when selecting a location to consider repair and maintenance
of the well as it must be accessible over time.
There are also provincially defined restrictions that must be followed,
stating minimum distances that must be maintained from certain objects.
50 ft from any septic tank or filter bed
5 ft from any property boundaries
20 ft from any road or public highway boundaries
6 ft from any building extensions
* Remember, well heads will be a minimum of one foot above finished
grade, therefore they should be in a location away from snow plowing
and not interfere with future plans for swimming pools, garages, etc.
Can you tell how deep the well will be and how much it will produce?
Unfortunately there is no way to guarantee with absolute certainty how
deep the well will be and how much water it will yield. Our extensive
experience and knowledge of the local geology does allow us to make
reasonable predictions though. Based on other wells in the area, we
will be able to give a reasonable prediction and a free written
estimate as to what is to be expected and what will be necessary to
adequately satisfy your needs.
How much water is enough?
Water demands vary for all customers, but Nova Scotia Environment and
Labour states that that the average adult uses approximately 50 to 75
gallons per day. Therefore a family of 4 would require a well to
provide 200 to 300 gallons daily.
Typically a well that produces 6 gallons per minute will adequately
satisfy an average sized home. When this yield is unavailable, drilling
a well to a greater depth will compensate flow by providing a greater
reservoir. The higher the static water level inside the well, the
greater the storage. Therefore wells with flows of ½ gallon per
minute or less can meet the demands required if enough reservoir is
provided.
How do I select a pump?
The pump should have adequate capacity for present and future uses.
Generally, pump capacity is equal to or slightly less than the safe
yield of the well so it will make use of the well's potential but not
overpump it. A pump with a capacity greater than the safe yield will
draw the water level down in the well too far, causing the system to
pump air or lose its prime. Continued lowering of the water level by
pumping may cause other difficulties in the well itself (decrease in
yield cloudy water, sand in water). The pump should also provide
adequate pressure for the present and future use, considering the
possibility of a lower water level in the well. We will suggest a
recommended pump size based upon your needs and circumstances.
Do I need to test my water, and if so how do I do it?
For most residential wells testing is not mandatory but it is highly
recommended. Nova Scotia Environment and Labour recommend testing for
bacteria every 6 months. Chemical quality should also be checked every
1 or 2 years. Frequent testing is beneficial not only for peace of
mind, but it will also warn you if any corrective measures need to be
taken to protect the integrity of your well, and also warns about any
activities that may be impacting your supply. We do not conduct
bacterial or chemistry tests, but instructions and sealed sampling
bottles can be obtained from any local laboratories.
For more information visit:
Nova Scotia Environment and Labour's clean water watch site
Canadian Ground Water Association.
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