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Module 5 — Monitoring and Maintenance of Your Water Well
See Module 7 "Troubleshooting Water
Well Problems" for more information
on well problems.
Even when the pumping water level
remains relatively steady, you need to do
regular annual maintenance, including
shock chlorination, to control bacteria
buildup. If you allow a well to deteriorate
for too long, it may not be possible to restore
its original capacity.
If the well yield declines, yet the non-
pumping water level remains constant, the
well may need to be serviced by a licensed
water well contractor. If your well is capable
of producing more water than you require,
you may not notice a decrease in well yield
unless you are routinely monitoring your
water levels.
A good time to take a pumping water level reading is during the day when the pump is
pumping, for example, at noon. By then there has been significant water use. Taking the
reading at the same time of day will give you comparable water levels, unless water use
varies considerably between seasons.
Now let’s look at the significance of some pumping water level measurements.
Example 3
In the table below, six readings were taken after the pump was on for 2 hours.
Month
Time
Water Level
Pumping Non-pumping
February 2, 2012
March 1, 2012
May 1, 2012
June 1, 2012
September 2, 2012
December 2, 2012
11:30
am
11:15
am
11:35
am
11:20
am
11:25
am
11:15
am
6.67
m
5.23
m
6.34
m
5.35
m
6.29
m
7.02
m
Interpretation: Since the levels are relatively constant, there does not seem to be a
problem with the efficiency of the well and no action is required.
Example 4
You look back over your records and find that, although the original non-pumping
water level has remained constant, the pumping water level has declined.
Month
Time
Water Level
Pumping Non-pumping
February 1, 2011
April 2, 2011
June 1, 2011
August 3, 2011
October 1, 2011
December 2, 2011
February 1, 2012
11:30
am
11:20
am
11:35
am
11:45
am
11:30
am
11:40
am
11:50
am
20.15
m
21.56
m
26.26
m
28.37
m
33.45
m
37.20
m
40.16
m
Interpretation: The screen (or slotted casing) may be plugged with sand, bacterial growth
or mineral incrustation. When this happens, the efficiency of the well is diminished and the
production rate (yield) drops.
To correct the problem, hire a licensed water well contractor to determine exactly
what is causing the reduced efficiency of the well. The screen (or slotted casing) may need
to be surged to remove sediment or in some cases may need to be replaced. You may need
to shock chlorinate the well to reduce bacteria or acidize it to remove incrustation on the
casing or screen.