Ask The Experts

The presence of Coliform bacteria in your well water indicates that some contamination of the well has occurred. This does not necessarily mean that the water is likely to cause illness, however, if follow-up testing indicates the presence of E. Coli bacteria, you should discontinue use of the well until it is cleaned up.

The first thing you should do is check on the condition of your well head to make sure that ongoing contamination is unlikely. Look for a loose or broken cap, ponding around the well head that might draw water around the well casing, or any other signs of a breach in the seal. A well head that is located in a pit, or is located in or very near the house is much more vulnerable to contamination. If you don’t know where your well head is located, it might be buried. We recommend that you have it extended above the ground for ease of access and to monitor the seal.

The basic decontamination procedure, sometimes referred to as shocking the well, consists of pouring between one half gallon and 2 gallons of over-the-counter diluted chlorine (Clorox) down the well casing. Remove the cap, pour the chlorine down the well, scouring the casing as you do so. Then draw water at an exterior tap until you smell the chlorine. Bypass any water treatment system, and plan on replacing any filters, remove any faucet strainers, and run water at interior cold water taps until you smell the chlorine at each, then allow the chlorine to sit in the system for 8 hours. You will then need to run the water until the chlorine odor is gone. This may take several hours. If your well has limited delivery capacity, take it easy as you do this.

Allow a week or two if possible after chlorinating before sampling your water to verify that the well isn’t susceptible to re-contamination. If the well fails again, call in a professional well company to determine why, and make any necessary repairs.

You are wise to want to test your water in advance of the drilling process. If your well water changes as a result of drilling activities you will need proof of its original condition. You can sample your water yourself and take the samples to a local certified laboratory, but your claims will have more credibility in a court of law if the samples are taken by a professional. Most home inspectors are familiar with water sampling and routinely provide the service to their clients.

There are numerous tests that can be performed but the costs can become prohibitive. We recommend a minimum regimen suggested by Penn State which consists of the following analytes: pH, Chloride, Total Dissolved Solids, Barium, and Coliform. If you do the sampling yourself, contact the lab first to get the proper sampling bottles, and to learn the proper testing conditions and holding times. There is no set time period before the drilling starts to take the samples, but the shorter the lapsed time the better, with a month or two being best.

Water quality can be adversely affected by gas well drilling operations, but so can well capacity. If you hire a home inspection company to do your sampling, we recommend that you have the technician perform a well flow test at the same time to verify that the water supply had sufficient capacity for your normal usage before the gas drilling gets started.

The water pressure varies on a rapid cycle as you describe because the expansion tank on your well system is waterlogged. The expansion tank, which is usually found near the location where the water pipe from the well enters the house, provides a cushion of air to absorb the changes in pressure that occur as the pump turns on and off. Since water can’t really be compressed and your expansion tank is waterlogged, the pump is turning on and off rapidly to try to deliver water at the flow rate dictated by the degree to which you open a faucet. Inspect the tank and the pressure regulator while the water is running. You will probably hear the pressure regulator clicking on and off. The proper cycle can vary, but should last at least 30 seconds between on and off. If the expansion tank is full of air as it should be, the pump will compress the air as water enters the system, allowing for a much longer on-off cycle. Rapid cycling of the pump is very stressful on the motor, so correcting the problem is important for pump life. While it may be possible to refill the tank with air, it is probably not worth the trouble since leakage within the tank will just result in the air being lost again. New expansion tanks are not very expensive, and the savings in pump life will be well worth it.

The discoloration of the water can be more problematic. Most wells deliver water with some amount of various minerals and fine particles, most of which are basically harmless. These can build up as deposits on the walls of your pipes, which then become scoured by the water flow when you open a valve more than usual, resulting in visible discoloration. Heavy water use can also result in discoloration of the water as lowered static water levels inside the well casing allow minerals deposited on the well casing to break loose and enter the water. These circumstances are quite benign, although water testing is recommended just to be safe. If the discoloration occurs during heavy rains, it may indicate surface water contamination. In this case further professional evaluation and testing is a must for your health and safety.

Authorities recommend that all private wells be tested for coliform bacteria once a year. Coliform is a type of bacteria that is most commonly associated with animal activity, and is a good indicator of the possibility that a water supply is contaminated. You should very definitely have your water tested, preferably when it is cloudy. The most likely scenario in your case is that surface water is entering the well during heavy rains, probably directly from the top of the well. Drilled wells into the ground are somewhat analogous to hypodermic needles through the skin. We use drilled wells to extract clean water from deep inside the layers of earth and rock, but they are also a shortcut for contaminates to enter the aquifer. Clean wells are just as important as clean needles. The well head should be above the ground where it can be inspected and guaranteed to be well sealed. The ground should slope away from the well to ensure that surface water won’t follow the well casing into the water source. The well should be located away from the perimeter drains around your house as well as your septic system. The well should be sufficiently deep to ensure that surface water cannot readily enter the water supply, meaning at least 50 feet below the surface. The sealed well cap should have a screened vent to allow air to enter the well as you draw down water, preventing a vacuum that will suck contaminates into any defect in the casing or cap. If these conditions are all satisfactory, it may be necessary to do some digging to assess the condition of the pitless adapter, which is the fitting that allows the water pipe to leave the casing four feet or more below grade to prevent freezing on its way to the house.

Wells with evidence of any contamination should not be ignored. The fact that no one has become sick should not be reassuring, because the type of contaminating bacteria could easily change at any time to one that is much more harmful, such as various strains of E. Coli. Ultimately you could need a new well or a purification system. Attend to this sooner rather than later, and we would recommend against drinking the water until corrections are made.

Yes, but it is not a simple process. Increasing the size of your tank alone will not do the trick. The tank is mostly full of air. It is called a pressure tank. Its purpose is to even out the flow of water as the pump turns on and off. Without the tank of compressed air, the pressure would fluctuate rapidly, and cause the pump to wear out prematurely. Increasing the size of the pressure tank would only increase the amount of air without much effect on the amount of water. However, a separate tank could be installed for water storage purposes. This tank would be fed by the pump in the well, using a float valve to maintain the water level in the tank, and a separate pump inside the house to pressurize the water for the rest of the house. A three hundred gallon tank would probably be sufficient for normal household use. You should consult with a well driller to determine if this type of system would work for you. The well will still need to have a minimum recovery rate, and the prospect that this rate can be sustained. You didn’t indicate whether the amount of available water has decreased over the years. In many areas of our community, increasing development and added wells have put added stress on the available water supplies and have lowered the aquifers to below the depth of older wells. If this is the case a new or extended well will be necessary.

You mentioned that the water gets cloudy when it rains. This is very troubling, because it means that potentially contaminated surface water is mixing in with the ground water. There are many possible reasons for this, but it usually happens because surface water is ponding around the top of the well and either seeping through a poorly sealed well head or seeping down along the outside of the well casing. The head of the well should be well sealed and high and dry. Have this further investigated, and have the water sampled when it is cloudy and tested for coliform bacteria at a local lab. In the meantime bottled water might be appropriate.