Water Quality Testing

Of course, we all want to drink clean uncontaminated water. If your home is served by a public water utility, they should treat and provide clean drinkable water to our homes. For those homes served by a private well, however, the home owner needs to be responsible to ensure that the water supply is safe. There are many potential contaminants that can get into water and make the water bad tasting or smelling and even unsafe to drink.

Bacteria, also known as total coliform, can make you sick if you drink bacteria contaminated water. Bacteria can enter water in several places, such as in the well itself, in a treatment system (like a contaminated water softener), or at a faucet. Bacteria is a living organism, so to properly treat it means killing the organism. The most common methods are one or more chlorine shock treatments and an Ultra-Violet (UV) system. A chlorine shock is a relatively simple process where chlorine is introduced down the well at specific amounts. The general rule of thumb is 2 quarts of chlorine per 100 feet of well depth. The proper dosage is important to addressing the bacteria issue and allowing time for the chlorine to do its function as well as leaving time to retest after the shock procedure is complete. When a total coliform sample is analyzed by a certified lab, they use a microscope to determine if coliform is present in the sample. Any result other than zero (0) indicates non-potable water that needs to be addressed before it can be safely consumed.

After the chlorine is added to the well, then all water spigots in the home (including the exterior spigots) should be turned on and water flowed through each fixture. Once the smell of chlorine is detected at each fixture, then the water supply system should stand unused for at least 12 hours to allow the chlorine to do its job. Then, run water at each fixture again until the smell of chlorine is completely gone at each fixture. Approximately a week later, a retest should be drawn to be lab analyzed. I’ve seen home owners pour gallons and gallons of bleach down their well only to have to wait 3 or 4 weeks to be able to drawn a retest sample. Most labs will not even accept water samples for coliform or e.coli analysis if a chlorine odor is present in the sample. Of course, time is of the essence during a real estate transfer, so abiding by the proper chlorine shock procedure is key to helping to keep the settlement timetable on schedule. The retest is needed to ensure that the bacteria issue has not returned. In some cases, a chlorine shock is only temporary and multiple shocks may be needed.

Another treatment method for coliform is the installation of an ultra-violet (UV) system. This is a system installed where the water service enters the home and uses UV energy to kill bacteria as the water supply passes through the system. Of course, humans cannot see ultra-violet light with the naked eye, however a small LED is normally located on the unit to tell the homeowner that the unit is powered. Simply seeing this LED turned on doesn’t indicate that the UV system is properly functioning and treating water, but only that the UV system is powered. The unit’s UV bulb needs to be replaced approximately every 12 months. From my discussions with homeowners with UV systems, most have no idea that the UV bulb needs to be replaced annually. Either the installer did not disclose the maintenance requirements with the home owner or it’s simply a case of lack of maintenance.

Another common group of contaminants in well water are nitrates and nitrites. Nitrates and nitrites are naturally occurring, but high levels of either in well water often indicates that runoff from a nearby farm or other fertilizer source has entered the water supply. A septic system located too close to a well or farmland adjacent to the well are both common sources of nitrates and nitrites. Nitrates and nitrites are both forms of nitrogen. The maximum level permitted in well water, per EPA standards, is 10.0 mg/L for nitrates. EPA regulations call for nitrite levels to be less than 1.0 mg/L as nitrites can be even more dangerous than nitrates.

Boiling water with high nitrate or nitrite may raise the concentration and increase the potential risks. High nitrate and nitrite concentrations pose an immediate threat to infants and have been linked to 'Blue Baby' syndrome which can be fatal without immediate medical attention. High nitrate and nitrite concentrations can also be hazardous to elderly people. A reverse osmosis system is the most common method of correcting a high nitrate or nitrite issues. Most licensed plumbers can install this type of system.

Other common contaminants in well water can include lead and iron. These metals can be introduced into the well system within the ground or within the plumbing in the home. Until the 1980s, lead-based solder was common when a plumber installed copper plumbing. Over time, the lead in the solder can leach into the water and, thus, contaminate it. High lead levels can cause kidney failure, damage to the nervous system, and can impede mental and physical development. Tested water with a lead concentration under 0.015 mg/L or iron concentration under 0.3 mg/L is considered acceptable according to the EPA. According to the EPA, "A first draw sample is a one-liter sample of tap water that has stood motionless in the plumbing pipes for at least six hours and is collected without flushing the tap (40 CFR 141.2). All tap water samples for lead must be first draw samples collected in accordance with 40 CFR 141.86(b)(2)".

Just because your home was built within the past few years doesn't mean you may not have high lead levels in your water. Some brass pipe fittings (sometimes present in new plumbing fixtures) have been found to leach lead into your water. I have inspected relatively new homes that had high lead levels in its well water and I suspect the cause was from one or more newer plumbing fixtures.

You can only find what you test for in water. You can’t test only for total coliform and nitrates and then ask the lab or the inspector what the lead concentration was for the sample. The basic water test performed during most home transactions with a well system are total coliform and nitrates. FHA and VA water analysis is also possible, and each consists of additional contaminants and is also, therefore, higher in cost. An FHA analysis consists of total coliform, e. Coli, nitrates, nitrites, and lead. A VA analysis consists of total coliform, nitrates, lead, iron, total solids, surfactants, and pH.

To help ensure uncontaminated water samples and accurate lab results, special care and procedures are needed when drawing water samples for analysis. A competent home inspector should be very familiar with the sampling procedures as prescribed by the lab that the inspector uses for analysis. A minor deviation in the sampling procedure can possibly contaminate the sample and may provide for a false positive in the lab report.

I’ve also seen some lenders require raw water samples to be taken. In other words, even if the home has a UV system or Reverse Osmosis system installed, some lenders will require these systems be bypassed or turned off before the sample is taken in order to obtain raw untreated water directly from the well. Before ordering a water quality analysis, it is wise to inquire with the lender to determine if they have any special requirements. Doing so may save some time and effort later when the inspector asks you about any lender special requirements. Some lenders may will accept the water quality lab report if it specifically states that the samples were drawn untreated (if the lender requires untreated samples).

Besides doing well water quality analysis at the time of the home transaction, I also recommend annual retesting of well water to help ensure a new contamination source doesn’t appear in the future.

Water Quality Testing

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