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Understanding Your Water System
Did you know……
More than 3 million Pennsylvania residents rely on drilled wells, hand-dug wells, cisterns and even roadside springs for drinking water?
Pennsylvania is one of the few states in the country without statewide regulations governing private well location, testing and treatment?
Water pollutants in water that can affect health often show no signs (taste, color, odor)?
Private water systems should be tested annually for total coliform bacteria?
Independent water testing by a certified laboratory can help homeowners avoid purchasing unnecessary water treatment equipment?
Your drinking water begins as rain or snow and ends at the tap in your home. With about 20,000 new wells being drilled each year and rapidly changing land use, information on proper maintenance of private water supplies becomes a necessary part of a homeowner's education. (Water Supply Basics Introductory Video)
Water Supply
An average of 40 inches of rain falls annually in Pennsylvania. Of this, seven inches becomes surface runoff. Thirteen inches percolate down to the groundwater. The other 20 inches are used by plants and is returned to the air as water vapor. Groundwater provides water for wells but most of the water slowly returns to the surface and emerges as stream or spring flow. (Water Supply and Conservation Video)
Siting, constructing and protecting your well
Proper location of the well is a critical first step. Imagine a fence with a 100 foot radius around your well. This is the contributing area for your well. Precipitation falling inside the fence becomes your drinking water, that falling outside does not. The above ground casing pipe should extend at least eight inches above ground level so it will not be covered under flood conditions. The slope of the ground should be away from the standing pipe so water does not collect around the pipe. A properly sited well should be at least 100 feet away from and up slope from septic system absorption fields, animal activity such as dog pens or barnyards; 50 feet from sewers or septic tanks; and 25 feet from a silo. Homeowner activities within the "fenced area" such as applying lawn or garden chemicals, fueling lawn equipment, and burning barrels are also potential sources of contamination.
Determine whether the well has a standard or a sanitary well cap. A sanitary well cap is recommended because standard caps do not prevent the entry of surface water or insects. Insects can hide and even nest under the well cap causing coliform contamination. Find out if the well is grouted, most wells in Pennsylvania are not. It is recommended that a sanitary cap and grouting be part of new well construction. This is important for preventing surface water from contaminating both the well and the ground water supplying the well and possibly other wells in the area. (Water Supply Construction and Maintenance Video)
Standard Well Cap versus Sanitary Well Cap
Testing well water using a state certified laboratory is the best way to ensure the safety of your water supply. Unlike public water systems which are regulated, and must run tests at prescribed intervals, private testing is all voluntary and your responsibility. Yearly testing for coliform bacteria combined with periodic testing for other pollutants is the best way to ensure safety and monitor your well water. Total dissolved solids (TDS) and pH analyses should be done every third year. These tests are generalized and provide a yardstick to alert the well owner in case surrounding land use causes a change in the well water quality. TDS and pH should not change much from year to year, so large changes may indicate a need for further testing. (Water Supply Testing and Protection Video)
Other factors indicating the need for testing are aesthetic. Obvious stains, odors or taste in water may cause the homeowner to test the water supply for possible treatment. Many of the pollutants causing these problems, such as those associated with hardness, are naturally occurring in groundwater. However, they can also be caused by surrounding land use activities. Your local Extension office or the Master Well Owners Network can help you with selecting the tests to confirm the form and concentration of the pollutant. Water should be tested by a certified water testing laboratory. The DEP provides a list of certified laboratories on their web site and testing for private water supplies is available through Penn State Agricultural Analytical Laboratory. Testing kits are available from your local County Extension office with instructions for taking and submitting samples. (Solving Water Problems Video).
Table 1. Routine water tests and treatment options
| Test | Desired Result | Treatment Options |
|---|---|---|
| Bacteria: The water is satisfactory when coliform bacteria are absent. Some coliform bacteria live in the intestines of people and warm blooded animals. Some members of the group are found in soil. While the coliform bacteria themselves generally do not cause disease their presence indicates disease organisms could be present. | Absent | Check for drainage problems and insect entry. Shock chlorinate the well and retest a week or more later. If contamination persists, consider purchasing water for drinking and cooking; developing a different water source; or treating the present source. Ultraviolet light and chlorination are two possibilities. |
| E. coli: A coliform bacteria specific to the intestines of humans and warm blooded animals, its presence indicates human or animal waste is entering the water supply. | Absent |
Same as for bacteria above. |
| Nitrate: Present at higher levels in water supplies located near intensively managed agricultural sites or near densely spaced or poorly operating septic systems. May cause health problems in infants under 6 months at levels above 10 mg/L. | Less than 10 mg/L NO3-N | The two basic types of treatment to remove nitrates from water are ion exchange and reverse osmosis. An alternative is to buy bottled water or use water from another source for infants under six months of age. |
| pH: A pH of 7.0 is neutral (neither acid nor alkaline). Water having a pH lower than 6.5 may dissolve some of the metals (iron, copper, lead, cadmium, zinc) used in plumbing, adding metals and taste to your water. Acid water does not affect plastic plumbing. | 6.5 to 8.5 | Low pH can be corrected with a neutralizing filter or by feeding soda ash into the water line. A neutralizing filter will add some hardness to the water. Soda ash does not add hardness, however it adds some sodium to the water. |
| TDS: High total dissolved solids may cause the water to have a noticeable taste. High total dissolved solids is the result of the water being in contact with rocks in the aquifer. Large changes in TDS can signal a change in water quality due to changes in land use in the area. | Less than 500 mg/L | Treatment is seldom needed for TDS however a reverse osmosis unit will greatly reduce the amount of total dissolved solids in water. |
Well Maintenance
If you have any maintenance done on the well that would result in removing the pump or opening the interior of the well, you should use shock chlorination to disinfect the well. Disinfection is accomplished by adding enough chlorine to reach a concentration of about 100 parts per million (PPM), about the same concentration used to bleach a load of white clothes. Unscented laundry bleach is acceptable for this purpose. Mix 1.5 quarts for each 100 feet of water in the well in five gallons of water. The mixture is then poured down the well and recirculated through a garden hose until chlorine is detected in the water from the hose. Turn off the hose and draw water from each cold water faucet in the house until the chlorine odor becomes apparent. After this use don't use the water is for 6-12 hours to allow disinfection to occur. When shock chlorination is done because of a positive test for coliform bacteria, at least a full week should pass before retesting the water supply.
Record Keeping
Records of the well log supplied by the driller, well construction information, testing and treatment system maintenance should be kept in a safe place.
Is treatment the best option or would you be better off replacing the water source? Most water problems can be corrected with treatment, but depending on severity, some treatment can be costly. Examples of new sources include drilling a new well or purchasing bottled water.
Questions to consider:
Is the treatment appropriate for the problem? For example, with hard water the equipment must remove calcium.
Is the treatment cost effective? Are there other brands or processes that will also do the treatment and how do they compare in cost?
Is the equipment guaranteed?
How long has the vendor been in business? Do they have a good reputation?
Does the equipment carry the National Sanitation Foundation (NSF) seal? This seal shows that the equipment has been tested and is effective.
Before purchasing water treatment equipment, homeowners need to understand their water quality problems. Penn State recommends testing by an unbiased certified laboratory. Penn State Cooperative Extension or Master Well Owners Network members can answer questions and help you select analyses based on signs observed in your water and interpret the results of the water tests. Factsheets with tips for buying equipment and information on the problems identified are also available online from Penn State or from your local Extension office.
Penn State Water Resources Drinking Water: http://water.cas.psu.edu/drinking_water.htm
Fact sheets, Links, Videos
Penn State Drinking Water Publications: http://water.cas.psu.edu/DWpublications.htm
Drinking Water Interpretation Tool (DWIT) - Online assistance in interpreting test results: http://www.psiee.psu.edu/water/dwit.asp
EPA Drinking Water and Health: http://www.epa.gov/safewater/dwh/
EPA Drinking Water Standards: http://www.epa.gov/safewater/standards.html
Master Well Owners Network: http://mwon.cas.psu.edu/
A network of trained volunteers dedicated to promoting the proper construction and maintenance of private water systems in Pennsylvania and throughout the Mid-Atlantic Region.
PA Department of Environmental Protection List of Accredited Water Testing Laboratories: http://www.depweb.state.pa.us/labs/cwp/view.asp?a=3&Q=515609&labsNav=|
Look under "Search Environmental Laboratories"
PA Department of Environmental Protection Public Drinking Water Information
http://www.depweb.state.pa.us/watersupply/cwp/view.asp?a=1251&q=447835&watersupplyNav=|30131|
OhioLine Ohio State University: http://ohioline.osu.edu/lines/ennr.html#EWTST
Well Water and Testing Fact sheets
National Sanitation Foundation: Drinking Water: http://www.nsf.org/consumer/drinking_water/index.asp
National Groundwater Association - Find a ground water industry professional: http://www.ngwa.org/programs/gw_professionals.aspx
Well Owner page of the National Groundwater Association: http://www.wellowner.org/
Information on locating certified well drillers
York Area Certified Well Drillers PDF (extracted from wellowner.org)
For more information contact:
Diane Oleson
112 Pleasant Acres Road
York, PA 17402
Phone: (717) 840-7429
This page last updated Monday, November 23, 2009
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