|
While changes in an aquifer can result in a well producing less water
than in the past, many people overlook the possibility of a pump or
well construction problem.
This page will help you determine which of these may be the cause of your problem.
Changes in the Aquifer
Seasonal Highs and Lows in Water Table
-
Water tables often fluctuate naturally from season to season. Find out more on how to track water levels over time at the Measuring Well Water Levels page.
-
In
general, the shallower the well, the greater the risk of water levels
falling in response to dry conditions. This is because many shallow
wells are drawing water from surface (water table) aquifers that are recharged primarily through precipitation.
-
To find out if you have a shallow well, check your well log or contact your watermaster for assistance.
Overpumping
-
The level of water in an aquifer can fall if water is being pumped at a rate that exceeds natural replenishment.
-
Pumping creates a cone of depression
in water table aquifers. This localized lowering of the water table
can be significant when pumping is excessive. In addition, if the
cones of depression for two or more wells overlap, well interference can occur.
-
In
some regions, the amount of water in the aquifer is limited due to
geology making the groundwater resource especially vulnerable to
depletion.
-
Your watermaster can provide more information about the likelihood of overpumping in your area.
Geologic Change
-
Since
wells draw water from aquifers below the earth's surface (in some
cases, many hundreds of feet below the surface!), the amount and
accessibility of this water can be altered by geologic events including
earthquakes, volcanoes, and mudslides.
-
In diagnosing limited water problems, consider the possible effects from recent geologic activity.
Pump Problems
Clogging
Malfunction
Pump Placement
-
If
the water level within the cone of depression drops below the depth of
your pump you will be temporarily unable to reach water. Decreased
water demand will allow the water level to rise again if the aquifer is
not already depleted.
-
In
some cases your pump can be lowered to increase access to aquifer
water. Consult with a well or pump contractor to determine if this is
an option.
Well Construction Issues
-
Decreased well efficiency can sometimes be associated with the following:
-
deposits in the well bore hole (this can occur naturally and over time the deposits need to be cleaned out)
-
a well that was never fully developed
-
inappropriate screening to allow for free water movement (wire wrap screens are usually preferable to slotted screens)
-
bacterial deposits (e.g. iron bacteria)
-
If
you know your well is shallow and you have had water supply problems in
the past, you might consider deepening your well. If at all possible,
contact the original contractor who constructed your well. Your local watermaster can also help determine if your well was constructed according to standards.
-
If
your well is unable to meet your domestic water needs you will need to
consider either deepening the existing well or drilling a new well.
Contact your well contractor or your local watermaster for help.
-
DO NOT attempt to deepen your well or construct a new well without the help of a licensed well contractor.
-
DO NOT pour water from another source into your well. Your well is connected to an aquifer and is not a storage device
|