The Sustainable Water Well Initiative Business Case Report
April 2011
Appendix 2: Common water well problems
There are a number of reasons why the quality or quantity of water that a well produces may
deteriorate over time, including structural deterioration of well or pump, local contamination or
depletion of the aquifer, and microbiological growth. Table 1 lists common problems well owners
face; any of these may lead to well failure – an inability of the well to provide safe water of
sufficient quantity. A comprehensive discussion of problems with water wells can be found in
“Groundwater & Wells” (Sterrett, 2008)[1], and “Water Well Rehabilitation: A Practical Guide to
Understanding Well Problems and Solutions” (Mansuy, 1999)[2]. For specific information on the
microbiology of groundwater and bio-fouling see the “Practical Manual of Groundwater
Microbiology” (Cullimore)[3].
Table 1: Common well problems, causes and results
Problem
Bio-fouling
Contamination
Sanding / Sediment
plugging
Mineral incrustation
Structural failure
Lack of water
Potential causes
- Poor well design (e.g. sumps)
- High entrance velocity resulting from poor
well design
- Over pumping combined with large
seasonal fluctuation of the water table
- absence or poor monitoring of
bacteriological activity
- absence or poor monitoring of the specific
capacity vs time
- Improper well construction (e.g. no or
inadequate seals)
- Improper well maintenance
- Point or non-point source pollution in
recharge zone
- Naturally occurring contaminants (e.g.
arsenic in Fraser Valley)
- Improper well design / construction
- Improper well development
- Poor well design
- Over pumping
- poor monitoring
- Poor well design
- Poorly designed well development
- Improper well construction
- Withdrawals greater than recharge (over
pumping)
- Cumulative effect of withdrawals of a series
of wells
- Lack of assessment of aquifer capacity
Potential results / indicators
- Reduced well yield / plugging
- Corrosion / incrustation
- Reduced well life span
- Well failure
- Reduced well/energy efficiency
- Reduced water quality (iron
manganese)
- Negative health impacts for
humans and / or livestock
- Enhancement of bio-fouling
- Reduced well/energy efficiency
- Reduced pump efficiency
- Increased rate of equipment
deterioration
- Reduced well/energy efficiency
- Reduced well yield
- Reduced well yield
- Well failure
- Negative environmental impact
- Salt water intrusion
Many factors influence the capability of a well to continue to supply water at consistent quality and
quantity, including design, construction, maintenance, operation, and environmental factors.
Neglected groundwater and wells can quickly deteriorate, increasing daily operation costs of well
owners and eventually requiring replacement as they pass the point where rehabilitation is
possible. To maximize the lifetime and performance of a well there are important steps to be taken
at all stages in a well’s life. The design of a well has immediate implications for the potential
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Prepared by GW Solutions Inc. for the Agri-Environmental Services Branch of Agriculture and Agri-Food Canada
The Sustainable Water Well Initiative Business Case Report
April 2011
lifespan of a well, potential yield, monitoring possibilities, operating and maintenance costs and
ease of protecting groundwater supplies from contamination. Early identification of problems in
wells can allow more effective and lower cost remediation and lengthen the lifespan of a well. Once
capacity drops by more than 20% preventative maintenance will less likely be effective and
mechanical or chemical rehabilitation methods may be required. If the specific capacity of a well
drops by more than approximately 40%, even aggressive remediation is not likely to fully recover
the loss in specific capacity[3]. Monitoring water level, yield and use is valuable for forecasting
water demand of an operation, understanding the dynamics of the well and forecasting its ability to
meet demand.
1.
2.
3.
Sterrett, E.R.J., Groundwater & Wells Third Edition. 2008: Johnson Screens.
Mansuy, N., Water Well Rehabilitation: A Practical Guide to Understanding Well
Problems and Solutions 1999: Lewis Publishers.
Cullimore, R., Microbiology of Well Biofouling.
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Prepared by GW Solutions Inc. for the Agri-Environmental Services Branch of Agriculture and Agri-Food Canada