The Rules for Buying a Home with a Well

Virginia is a "buyer beware" state. Any well or groundwater problems not detected by the buyer during the sale process become the  buyer's problem upon closing the sale. There is no legal recourse back to the seller. These are the rules for buying house with a well to help you to avoid properties that are potential big problems before you close on a house.

1. The house must have 2-3 acres of land.
2. There must be a well completion report on file with the county health department that shows:
1. The well stabilized yield should be greater than or equal to 6 gallons/minute
2. The well should be drilled and more than 100 feet below grade (deep)
3. The well should be a 6 inch diameter pipe with a bolted cap sticking at least a foot out of the ground
4. Do not buy a home with a shared well
5. The well was drilled after April 1, 1992 (under the current regulations).
6. The well head must be at least 100 feet from the nearest edge of the septic drainfield and at least 50 feet from the nearest corner of the house.
7. Health Department records show regular septic pump outs at least every 5 years. Annual inspections for alternative septic systems should be on file.
8. Don’t buy a house with a well in Karst terrain.
9. Test the well water for all the primary and secondary contaminants regulated under the safe drinking water act as well as pesticides. At the very least test the well water for Total coliform, E. coli, nitrate, lead, iron, pH, hardness, and residual chlorine.
1. Don’t buy a house with a well that found E. Coli is present in the water or nitrate at more than three times background levels (of 2mg/L).
2. Don’t buy a house that found lead present in a flushed sample.
3. The well water must have a pH > 6.0
10. Draw a glass of water from the cold tap in a bathroom sink and taste it. Don't buy a house with water you don't like. 

You need to make sure that the well is constructed properly and that the groundwater that is drawn into the home is safe to drink. Though there are many treatment options to fix contaminated water, you might not want to buy problematic water and some water problems can create a cascade of issues, so I have eliminated them. If you are buying a house, you need to make sure that you will have an adequate and safe water supply. This is not the same thing as strategies to live with diminished well yield or fixing your existing water quality problems. This is your one chance to make sure the water supply to the home is acceptable before you buy the home. There is no recourse after you buy the home.

Virginia Tech recommends that buyers should engage a licensed well contractor to assess the well and any treatment. As part of the assessment, the home buyer should obtain a copy and review with the licensed well professional the "Water Well Completion Report" and the septic system (or AOSS) repair/permit history and the history of septic tank pump-outs. This information is on file at the local health department. 

If you see more equipment than a blue pressure tank in the basement you need to know what water treatment equipment is being used, why it was installed and if it is working properly. It is not always obvious what a particular piece of equipment is just by looking at it because manufacturers tend to use the same casing style for all their products. You will need to test the water before the treatment equipment and after the equipment and determine if you can or want to live with the findings. There is a limit to the life cycle of any equipment and wells themselves. How old the equipment is can determine how effective it is and how long it will continue working.

For purchase I would recommend a broad stroke water test that looks at all the primary and secondary contaminants regulated under the safe drinking water act as well as pesticides. These kinds of tests exist. An example is the WaterCheck Deluxe plus pesticides test kit from National Testing Laboratories which is an EPA certified laboratory would work. There are others. Buying a package reduces the cost though the drawback is these packages are performed at a lower sensitivity level and WaterCheck was the most economical test I found. All the packages compare their results to the  US EPA’s Safe Drinking Water Act limits for the primary and secondary contaminants. Since there are no regulation for private well water, that is a reasonable standard to compare the water test results to. Be alert to anything that should not be in groundwater. The presence of low levels of man made contaminants may be an indication of a bigger problem.

There are no national standards for construction of private water wells, thought in recent decades more and more states have developed standards at least for construction. Wells are typically managed and regulated by the State or Local Health Districts, state departments of the environment or ecology. You need to know what the regulations are in your local area and when they were implemented. In Virginia the regulations went into effect in 1992. You want a well built to the current standards, but the truth is that the well may not last more than 30-40 years. Geology matters in how a well ages. Check water level and yield in an old well yield diminishes over time.

Most states require a permit to drill a well and well drillers to be licensed. Make sure you know what that means in your location. In Virginia that is a decent standard, but in Pennsylvania anyone with $60 can get a well driller license, there are no minimum training or knowledge required there. There are still a few locations where a shallow dug well does not require a permit or license. Know these things when you go looking for a house with a well.

10 Rules for Buying a Home with a Well and Septic System

Well and septic systems are simply mechanical components to a house. What makes them different is that they are specifically excluded from home inspections, are very expensive to replace and essential. There are times and instances that a well or septic system has no good replacement location and then the home owner has a large problem on their hands that will cost tens of thousands of dollars to solve. Make sure that you do not buy someone else’s problem and make it your own.  When shopping for a home, there are some “fatal flaws” that can quickly and easily be identified. This is the list of quick observations and the reasons they might be a problem for a well and septic system to quickly eliminate properties as potential big problems, require further investigation or to factor the price of repair or replacement into an offer on a house. (For updated articles on this topic see "The House has a Well...") 

1.      The house must have 2-3 acres of land.

2.      Do not buy a home with a dug or bored well.

3.      The visible well should be a 6 inch diameter pipe with a bolted cap sticking a foot out of the ground.

4.      Water from the road, driveway, and downspouts should not drain to the well.

5.      Rainwater should flow away from not to the wellhead.

6.      If the well was drilled before 1992 don’t buy the house.

7.      The well head must be at least 100 feet from the nearest edge of the septic drainfield and any backyard chicken or poultry yards and coops. 

8.      The well head must be at least 50 feet from the nearest corner of the house.

9.      Ask to see the maintenance records for the septic system and well along with water test results (having records is an indication of proper maintenance).

10.   When you make an offer on a house a satisfactory water test and a professional septic inspection should be included in your contingencies.

This is what a drilled well looks like

The well and septic system should be easily identified and pointed out. A well should be a 6 inch diameter pipe with a bolted cap sticking a foot or more above the ground surface. What I have described is a drilled well there are also dug and bored wells. Do not buy a home with a dug or bored well. Those types of wells fail sooner, are prone to go dry during droughts and because they are shallow (less than 40 feet deep) are more subject to pollution. Drilled wells are more than 40 feet deep, typically more than 100. In Virginia well drillers are required to file a drilling log with thecounty and comply with drilling regulations since 1992. If the well was drilled before 1992 don’t buy the house unless you have factored well component replacement into the price and you should be thinking about the costs and possibilities of well replacement.  While many wells will last decades, it is reported that 20 years is the average age of well failure. Older well pumps are more likely to leak lubricating oil or fail. Well casings are subject to corrosion, pitting and perforation. Septic drainfields also have a limited life. The life of a septic drainfield is dependent on how the system is managed, the frequency of septic tank pump outs, and the number of people living in a house, but 20-30 years may be the life of those systems, too.

If a property has a well and septic system and has less than 2-3 acres, do not buy it. This is simple there will not be enough room for a replacement well and septic system when the time comes (all systems fail eventually) and the well is likely to be too close to the home’s own or the neighbor’s septic system. The most common contamination problem for a well is an adjacent septic system and research done in Duchess county New York identified density of septic systems as an easy indicator of nitrate contamination to groundwater. The Dutchess County study and another study performed in North Carolina found that overall average density of on-site waste disposal (traditional septic or alternative) should not exceed one unit per 2-3 acres for an average size house to ensure water quality and recharge in groundwater supplies. The controlling factor in minimum lot size requirements in the northeast appears to be maintaining water quality, not groundwater recharge. Adequate dilution, soil filtration and time are necessary to ensure sustainable water quality. It is often surprising how close to a private well the recharge zone is.

Failed drainfield. Picture from NC Health Department

 So, while you are walking around outside make sure that the well head is at least 100 feet from the nearest edge of the septic drainfield and 50 feet from the nearest corner of the house. It can often be difficult to identify a septic drainfield while walking in the yard. Newer systems often have plastic caps to the distribution valve, but older systems often do not- the distribution valve is buried. In Virginia (and most places) if a well is more than 100 feet deep the septic leach field need be only 50 feet away, but there are many wells like mine that have more than one water level and the shallower one is less than 100 feet deep (in my case 46 feet) making the well much more susceptible to contamination for the septic effluent leaching into the ground. If the well is too close to the drainfield, move on to the next house in your search, the well could too easily be impacted by the septic drainfield.

The final treatment for all septic systems is septic system effluent (after any intermediate treatment steps in an alternative system) is filtering of the wastewater through the soil. The method of sewage treatment with a septic system is soil organisms and soil filtration and adsorption. Whatever was flushed down the toilet or poured down the drain over the years has found its way into the drainfield and potentially to the groundwater. Not only should the well head be at least 100 feet from the nearest edge of the drainfield, the drainfield should be downhill and down gradient for the well. The land that my house sits on has a predominately southeast slope to the river at the bottom of the property. It is a fairly safe bet that the groundwater flows with the land topography towards the river.  

Two septic tank lids and filter for alternative septic system. 

Look for the septic tank. The tank should not be entirely buried and at least one port should be visible in the yard. If the tank is entirely buried- move on, do not buy the house because it is a safe bet that the tank has never been pumped and the entire septic system will have to be replaced.  The solids, scum and grease that accumulate in the septic tank need to be pumped out and disposed of every few years. If not removed, these solids will eventually overflow the septic tank, accumulate in the drain field, and clog the pores in the soil and the openings in the pipes. While some clogging of soil pores occurs slowly even in a properly functioning system, excess solids from a poorly maintained tank or a tank where enzyme additives were used instead of pumping the tank can completely close all soil pores so that no wastewater can flow into the soil. The sewage effluent will then either back up into the house, flow across the ground surface over the drain field, or find another area of release in the septic system. In some cases where the drain field has become clogged and no longer can adequately absorb the wastewater, the toilets and sinks might not drain freely. A black residue may remain at the bottom of the toilet.  If the drain field can absorb the effluent, but no longer treat it, the sewage may contaminate the groundwater or surface water with fecal coliform bacteria. On a dry day if there is a soggy area of the yard the drainfield may already be failing.

The reason a well should be more than 50 feet from a house is that in Virginia (and many other locations) building codes require that a construction site be pretreated for termites, and many homeowners spray gallons of pesticides into the ground to treat or prevent termites.  (There are other approaches to termite management, but most homeowners do not use them. Termite bates are easy to spot in the yard and indicate that chemical barriers are not used. ) http://greenrisks.blogspot.com/2011/10/low-impact-termite-management.html The most popular professionally applied conventional chemical treatments on the market are Premise (imidacloprid), Termidor (finpronil), and Phantom (chlorfenzpyr). These chemicals range from slightly toxic to very toxic and vary in their solubility and affinity for soil. They are less environmentally persistent and more rapidly biodegradable, than previous generations of chemicals. This all means that they breakdown faster and do not last as long, but also may allow their breakdown products to migrate to the shallow groundwater.

Sentricon termite bate station

Other posts:
https://greenrisks.blogspot.com/2019/06/what-to-know-when-buying-home-with-well.html
https://greenrisks.blogspot.com/2020/03/what-to-know-if-buying-house-with-well.html

Test a Well for Chemical and Bacterial Contamination Before You Buy a Home

Picture from Moen Website

If your home or a home that you are considering buying has a drinking water well that is contaminated, it could significantly impact your health and the value of the property. Never buy a home with a contaminated or failing well. Testing a well is a very important part of a real estate transaction, and only by fully testing the water can you be certain that it is not contaminated. When buying a home with private water well you need to understand at a minimum the basics about groundwater, the age of the well, the local geology, water quality, and water quantity.  Most single family homes transactions only test a well for coliform bacteria contamination, nothing more. Total coliform bacteria is always present in manure and sewage, but is also present in soil and vegetation and surface water. The presence of coliform bacteria may indicate that the well has been impacted by a nearby septic system or manure composting; it can also mean that surface water is getting into the well either directly through a failing casing or grouting or improper construction or well cap or by other means. Absence of coliform bacteria only means that water is not contaminated by septic and surface runoff, but the water might be contaminated from other sources.

In a world not subject to chemical contamination of the aquifer (from pesticides, herbicides, solvents and fuels present in stormwater runoff) or high natural concentrations of arsenic or metals, a coliform bacteria test is a fairly decent test to determine potential outside impact to a well and sound construction. If you do not test for it you will not find it. Water contains a variety of impurities beyond the simply H2O molecules. Not all of the impurities and contaminants are bad, some make water taste good.  The US EPA’s Safe Drinking Water Act does not protect private wells; however, the limits for the primary and secondary contaminants are a good standard to compare water to when testing a well.

Due to its protected location underground, most groundwater is naturally clean and free from pollution. Typically, the deeper the well the less likely is it to be contaminated from nearby industrial operations. However there are a number of threats to drinking water: improperly disposed of chemicals; animal wastes; pesticides; human wastes; wastes injected deep underground; and naturally-occurring substances can all contaminate drinking water and make it unsuitable for drinking or make the water unpleasant to drink. It is important to know the land history of a site. Homes built on former disposal sites- farm dumps, landfills or former military operations are particularly susceptible to contamination. Former agricultural properties should be tested for pesticides, fuels and solvents because farmers often have fuel tanks and repaired farm equipment with solvent that were improperly disposed of over the years.

The nightmare scenario is what happened in Sterling, Virginia as documented by Rosemary Stephen in her article “Trichloroethylene(TCE) Water Contamination.”  The short story is that for twenty or thirty years homeowners in a community in Sterling, Virginia (a community in Loudoun County) were drinking water contaminated with TCE and its degradation products. The homes had been built on and old landfill and back in 1988 the Loudoun County Department of Health and the EPA had found traces of TCE, its degradation products and pesticides in three residential wells, but because the contamination was below the regulated maximum contaminant level (MCL) no further investigation was performed. Apparently, the oddity of finding a solvent in groundwater in a residential community did not immediately prompt further investigation. The water was within safe limits and thus was fine.

However, the water in the neighborhood was not fine. In 2005, 68 more wells (in the community) were tested by the Health Department. “Forty-five wells tested positive for TCE; 17 of these wells contained concentration of TCE above the maximum contaminant level (MCL) of 5 micrograms per liter (mcg/L) while 28 wells contained TCE, but below the MCL.”  The site was declared a CERCLA (Superfund) site in 2008. Between 1988 and 2005 no testing was done on the individual homeowner wells. The water was consumed by the young and old and the homes were bought and sold. If your home had been declared within a Superfund site, it is very likely that the value of the home would be impacted.

To be prudent and smart you need to test the well for likely sources of contamination. When I was working as an Environmental Engineer, the biggest challenge was to adequately research the history of a property and then test the soil and groundwater for contamination in the areas most likely to be contaminated. Testing is very expensive, so it is virtually impossible to fully test soil and groundwater.  In buying a single family home, you do not have any of this information or resources available to you. Neighbors can be useful or just have no understanding of environmental and groundwater issues and tell you nonsense they’ve heard. If someone asked me about groundwater in my community or my opinion about any specific well, I would tell them, but they would not know my level of expertise. While there are some good historical records available for industrial and commercial properties there is very little information available for residential properties. The department of health often has some useful information about water quality in the county and septic systems, but rarely has any water analysis data available.  Chemical analysis can be very expensive, and there is no requirement that private wells be tested at all and most health departments do not have budgets for testing water quality.  

However there are screening packages available from National Testing Laboratories that could serve to screen water wells for all the primary and secondary contaminants before you purchase a home. Their WaterCheck with pesticides package is a broad stroke test, testing the water for 103 items including Bacteria (Total Coliform and E-Coli), 19 heavy metals and minerals including lead, iron, arsenic and copper (many which are naturally occurring, but can impact health); 6 other inorganic compounds including nitrates and nitrites (can indicate fertilizer residue or animal waste); 5 physical factors including pH, hardness, alkalinity; 4 Trihalomethanes (THMs) and 47 Volatile Organic Chemicals (VOCs) including Benzene, Methyl Tert-Butyl Ether (MTBE) and Trichloroethene (TCE). The pesticide option adds 20 pesticides, herbicides and PCBs.  WaterCheck with the pesticide option costs $217. You will also have to pay overnight shipping cost ($40-$70) to return the package.   

In order to complete the analysis before you are committed to purchase a home, you will need to purchase the WaterCheck package before you put an offer on a home. Have the package ready, read the instructions and include in the purchase offer a water analysis clause that specifies that the contingency period must be long enough to allow for the analysis and the water quality must be acceptable to you. At least that is what I used; I did not specify that the water quality must be within all primary MCLs and within recommended secondary contaminant levels because some of the secondary contaminants are common minerals in groundwater and are regionally high. Make sure that you test the water before any treatment equipment that the home may have, activated carbon filters and distillation units can remove some solvent and hydrocarbons from the water. If any water treatment systems exist in a home you want to test the water before treatment and after treatment so that you understand what the water is being treated for and if the treatment is effective.  

My water tested "hard," but I was fine with that. The levels of all other secondary contaminants were within recommended limits. All primary contaminants were below the MCL and all hydrocarbons and solvents were not detected at any level. There is no good explanation for the presence of volatile organic chemicals in a drinking water well. Even extremely low levels may indicate a significant problem.  Also, be aware that a common nuisance contaminant in this part of the county is iron bacteria. Iron Bacteria can cause both unpleasant odors and taste to your water as well as cause clog screens and ultimately foul a pump. There is no EPA approved analysis for these bacteria, but there are assay tests. An easy way to see if there are iron bacteria in a home is to stick your hand in the toilet tank and feel the flapper. Iron bacteria leave slime on the flapper and you can feel it with your fingers. Of course if the tank is brown or orange there is likely an iron problem or the iron bacteria has gotten completely out of hand. Once iron bacteria are in a well, it is really hard to get rid of, but fairly easy to control with annual disinfection.  When I bought a home I wanted the water to be acceptable as it was. Water systems are dynamic and do change, and over time I discovered that slime was appearing on my toilet flappers and have had to address the iron bacteria and the annoyance of the annual treatment (which causes all the manganese and iron particles that treatment freed from the well to remain in the water supply until the well fully clears).

To ensure that you will have adequate time to test water quality before releasing all contingencies, you will need to check with the laboratory for turnaround time to make sure your contingency period is long enough. Do not let a realtor pressure you to skip this test because it could take a couple of weeks. When I bought my home in 2007 I could only negotiate a 10 day contingency period and had to pay a huge premium to have the well analysis done on a rush basis. Remember the mortgage takes longer so just include the time- fight for it; this is the most money you will ever spend. While you are at it, check when the last time the septic tank was pumped and the septic system inspected.

Is the Water Well Safe? Is the Water Well Good?

When I alerted all of the homeowners of my little neighborhood of the Prince William County Virginia Cooperative Extension (VCE) Office drinking water clinic for testing well water next week, one of my neighbors told me “I don’t have to test my water until I sell the house.” I was absolutely silenced by that comment. How do you respond to that?  In fact my neighbor does not ever have to test her water in Virginia. It is only that many mortgage companies require a basic test of water potability to close a mortgage. This most basic test of potability consists of a bacterial test and is written into most purchase contracts. My neighbor has lived in their house for 8 years with no intention of moving, so in essence she told me that she does not intend to ever test her drinking water. Because she does not “have to,” my neighbor has no intention of monitoring the most basic health risk- contaminated water. In fact a malfunctioning well (either due to contamination or component failure) can be expensive to repair or replace, but the harm from contamination is only likely to impact your family’s health and Virginia lets you do as you want. As long as the well continues to pump water you can ignore it.

The most basic water test usually performed at purchase or commissioning of a well is for total coliform bacteria. Total coliform bacteria is always present in manure and sewage, but is also present in soil and vegetation and surface water and while it may indicate that the well has been impacted by a nearby septic system or manure composting, it can also mean that surface water is getting into the well either directly through a failing casing or grouting or improper construction or well cap or by other means (karst terrain). In a world not subject to chemical contamination of the aquifer (from pesticides, herbicides, solvents and fuels present in stormwater runoff) or high natural concentrations of arsenic or metals, a coliform bacteria test is a fairly decent test to determine potential outside impact to a well and sound construction. Well water that test positive for coliform is often tested for E. coli (Escherichia coli) or fecal coliform types of coliform bacteria. E. coli or fecal coliform bacteria are present only in the digestive systems of humans and animals and a positive test result indicates contamination by animal manure or sewage. If a well tests positive for E. coli or fecal coliform the water is unsafe to drink (it is “poopie” water). Such wastes may include one or more of a variety of potentially pathogenic microorganisms such as Salmonella, Shigella, enteric viruses, Giardia or Cryptosporidium that may be present in human or animal manure and can cause severe illness. People have died from drinking water contaminated with cryptosporidium.

In Virginia and most other states, regulations for private well construction and testing apply only to newly constructed wells. In addition to various construction requirements (which include setback distance requirements from certain potential pollution sources such as septic tanks and leach fields), newly-constructed wells must be tested for the presence or absence of coliform bacteria. Although some municipalities and counties in other states have private well testing programs, only New Jersey has a statewide private well testing program which requires regular testing of private well water and treatment of the water if any of the standards are exceeded. Everywhere else in the country you are on your own to ensure that you are drinking safe and clean water.

The issue of whether water is safe to drink is separate from whether the water is free of unpleasant contaminants like iron, manganese, chloride, and low levels of sulfur or if the well can deliver adequate amounts of water.  Groundwater can change over time, become contaminated or dry up from inadequate recharge or overuse and wells do not last forever.  There are three aspects to a private well- the well and well system, the water quality and the water quantity. Failure of any of these can impact your life and the value of your home. The well is essentially a hole in the ground. Shallow wells (those less than 50 foot deep) are generally dug or bored into the ground and have larger diameters (2-4 foot). Shallow wells are more prone to contamination and drought and bored wells have the shortest life. Deeper wells are called drilled wells because they are drilled into the ground to depths from 50-450 feet or more and because of the need for drilling rigs cost much more to build. The diameter of a drilled well is 6-8 inches.

Generally, drilled wells provide a safer source of drinking water, and are less often impacted by drought. In igneous and metamorphic rock systems like the Piedmont of Virginia, the fractures and fault lines formed in the rocks store and transmit groundwater. The size and number of water bearing fractures varies and there is a wide variation in well yields from under 1 gallon per minute to over 50 gallons a minute depending on location and specific site geology. Fractures can become fouled with mineral deposits or iron bacteria or simply go dry over time. The specific geology and water quality will determine the life span of a well. Aquifers can go dry unexpectedly, but all wells will fail over time. The lifespan of a drilled well is assumed to be 20-50 years, but varies tremendously based on site specific conditions. I personally know of a drilled well that lasted almost 65 years before the well stopped producing water, but if you are buying a home with a well over 20 years old you will need to budget for drilling a new well. Make sure that is considered in the price you pay and that the property has another location to drill a well.  

The well system consists of the well, the well casing, the inlet for water, and the pumping system. The casing is the structure around the well hole to prevent its collapsing. It could be a steel or plastic casing or an open hole in the bedrock. In this part of Virginia, the Piedmont, the top of the well is lined with steel for 50 feet and then the well is open in the bedrock allowing the water to flow into the well. The well casing will rust over time. The well casing should be 1-2 feet above the land surface to make sure that during storms and flooding that nothing washes down the well. There should be no holes or cracks in the visible portion of the casing and the well cap should be tightly bolted closed.

The pumping system includes the pump, piping and electrical connections to pump water from the well into the house and a pressure tank to maintain constant water pressure in the house. Shallow wells usually use centrifugal pumps and are often located in a pump house or the basement. Drilled wells have submersible pumps. The pump and pumping systems are the most likely components to fail in a well. The average life of a submersible pump is variously reported as 12-15 years, but many pumps fail in the first few years. The essential components of a modern drilled well system are: a submersible pump, a check valve (and additional valve every 100 feet), a pitless adaptor, a well cap, electrical wiring including a control box, pressure switch, and interior water delivery system. There are additional fittings and cut-off switches for system protection, but the above are the basics and each and every component must work properly for your well to function properly.

In addition, in order for a well to keep supplying water to your home the components within the basement must all continue to work. These components provide constant water pressure at the fixtures in the house and the electrical switch that turns on the pump. The pump moves water to the basement water pressure tank, inside the tank is an air bladder that becomes compressed as water is pumped into the tank. The pressure in the tank moves the water through the house pipes so that the pump does not have to run every time you open a faucet. Bladders and electrical switches will fail over time and valves and switches and impellers on the pump can break, foul or find any number of ways to fail. You have to assume that pump systems that are older than 12 years are on borrowed time. It does not mean that a pump system cannot last 25 years or more, but I would not bet on it. Also, if your pump fails consider replacing other components of the system at the same time.

If buying a home with a well you need to consider the construction, condition, age and location of the well in addition to water quality and quantity. Make sure that the well is uphill (up gradient) and at least 50 feet (preferably 100 feet) from potential pollution sources like septic tanks, septic drain fields, stormwater drainage ditches and sources of contaminated runoff. Clay loams or silty clay soils filter pollutants and protect an aquifer. If there is not a lot of top soil and overburden or the soils are sandy, make sure that the well is deep and test the well for chemical contaminants before purchase. A shallow water table and fractured bedrock may provide larger quantities of water, but the shallow fractured rock systems are easily contaminated.

When testing your water you need to consider nearby likely sources of contamination and test for those contaminants, but the contaminants that occur in nature and from human and animal waste that can impact health need to be tested for:  E. coli or fecal coliform and total coliform, nitrate, sodium, sulphate, lead, floride and copper. In addition, water taste and aesthetics are impacted by hardness (calcium carbonate), chloride, iron, manganese and pH and you should test your water for these before you buy a home or purchase a treatment system. 

Purchasing a Home with a Water Well-Caveat Emptor

In rural areas or here on the edge of nowhere private wells supply water to homes. If you are thinking about buying a home with a private water well you need to understand at a minimum the basics about groundwater, the local geology, water quality, how the well system works, how deep the well is and how old and what size pump it has. These are the factors that will impact water reliability, water quantity, and water quality.  It would be a real shame to discover after closing on home that the drinking water well does not supply enough water for you to do laundry in the summer, goes dry in a drought or that the water is contaminated or has an unpleasant taste or smell. It can be very expensive to replace a well or well components, engineer solutions to water supply problems and install and maintain a water treatment systems. A home inspection tells you nothing about the well or septic system.  

About 15% of households in the United States depend on private wells including over a million each in Virginia and Pennsylvania where I once lived. In its most basic sense a private water well is a hole in the ground that is drilled, driven, or hand dug to supply water for a household. Most wells today are drilled by a cable tool or by air-rotary drill. Hand-dug wells are usually very old but still exist; and are very susceptible to pollution from surface sources and may also present easy routes for surface contaminants to enter the aquifer. If considering purchasing a home with an old hand dug or driven well factor in the cost of replacing the well with a modern drilled well in the price and be aware that not all pieces of land have suitable aquifers to tap.

The aquifer is the groundwater. Aquifers may occur a few feet below the land surface, but useful aquifers are more commonly found at depths greater than 100 feet in Pennsylvania and 100-400 feet beneath the bedrock in Virginia. Some groundwater occurs in the pore spaces of solid rock, but most usable groundwater occurs in cracks and fractures in rock layers or between sand and gravel particles of unconsolidated layers. Except in Karst terrain which has its own special problem, groundwater normally occurs in small spaces within the geological layers and not as underground lakes or rivers.

 Geologic formations called aquitards are usually made of clay or dense solid rock. The aquidards inhibit groundwater infiltration, and restrict groundwater movement into and between aquifers. Aquitards located above and below an aquifer form a confined aquifer. If a well is drilled into a confined aquifer, artesian pressure forces the trapped water to rise in the well above the aquifer if the pressure is great enough, the water may even flow without pumping to the land surface creating an artesian well. The downside to a confined aquifer is that recharge is limited. The coastal plain in Virginia has a confined aquifer and is really only recharged at the “fall line.” A groundwater aquifer without an aquitard above it is an unconfined aquifer and more susceptible to contamination, but more easily recharged by precipitation. Without pumping, the water level in wells in unconfined aquifers is the same as the aquifer. The county department of health, the extension office, the local offices of the U.S. Geological survey are good places to find out about the local geological and groundwater conditions. You need to understand what type of aquifer you are dealing with to be aware of the factors that impact water quantity and quality. There are dry years and wet years and water availability will vary, though it is not always obvious. The groundwater aquifer tapped for water is not seen so you need to understand it to be aware of the water budget that you will have to live within before you run out of water.

In many locations private wells are not regulated or only minimally regulated. Virginia now has well drilling regulations and standards, but those only apply to wells drilled after 1992 and require a health department permit for drilling new wells and repairs of older wells.  If you buy a home with an existing well- buyer beware. It is your responsibility to make sure that you know what you are buying. The type of well, the well yield, the condition of the well and the quality of the water is your responsibility to determine before purchase. The type of well and the configuration will be determined by the age of the well and geology.  While there was a time when some wells were hand dug with a shovel or hand driven using connected pieces of pipe (as featured in Hallmark channel movies) most wells use equipment to drill, dig or drive pipe and by and large modern wells are drilled. Nonetheless, there are thousands of home supplied with water from older wells. Ask, look, investigate. Check driller’s logs filed with the health department.

The type of well is determined by geology and history. Sitting as my home does in the Culpeper groundwater basin above fractured rock and bedrock, drilled wells are predominant. When drilling a well, it is typical here and now in Prince William Virginia in the twenty-first century to drill the well through a first and second layer of groundwater. I have a second groundwater level I can drop my pump down to if need be in a drought.

Drilled wells penetrate about 100-400 feet into the bedrock. To continually supply water, a drilled well must intersect bedrock fractures containing ground water. The art of well drilling is having a feel for what a fracture looks like at the surface- knowing where the water is. A trained and experienced hydro-geologist can generally find the fractured rock zones, or the intersection of two fractured rock zones using aerial photography and the fracture trace technique. It can be expensive to hire a professional hydro geologist, but the cost is worthwhile for difficult areas.  Where I live in the Piedmont region of Virginia the local geology is a fractured rock system that is water rich with more than one groundwater layer, so using hydro geologists is not common, but I do know of a couple of instances where several wells were drilled before obtaining adequate water flow and it might have been more cost effective to locate water before the house was built or to design a different well system. The Piedmont tends to be so water rich that alternatives are not in common use. In some regions low production wells are common.

If a property has a low producing well, there are ways to deal with it. First is water conservation and the second is to increase water storage within the system. Water conservation involves changing water–use behavior such as taking shorter showers, but usually involves installing water saving devices like a front-loading washer (saves 20 gallons of water for each load),low flush toilets, flow restricting faucets and shower heads. Installing watersaving appliances can reduce household water use by up to 30%. Water conservation may solve the problem of a 5 gallon a minute well, but increasing water storage can make a reliable 1 gallon a minute well viable for a modern household. An intermediate storage system consisting of a storage tank ,reservoir or cistern that can be installed between the well and pressurized distribution system. The reservoir serves as the primary source of supply for the pressure pump supplying peak demand. Ideally, the storage tank or cistern should be able to hold at least a day’s water supply and be regulated by a float switch or water level sensor. A 1 gallon a minute well can pump 1,440 gallons per day more than adequate for a household of almost any size.  The rule of thumb is to size a storage tank or cistern at 100 gallons per person in the household. It is much cheaper to installed intermediate storage than keep drilling wells.   

Once you have determined that the water supply is adequate, the water quality should be checked. The quality of the groundwater is a characteristic of the aquifer and the ability of your local geology to protect or impact your aquifer. The most common sources of pollution to groundwater supplies come from two categories; naturally occurring ones and those caused by human activities. Naturally occurring contamination are produced from the underlying soil and rock geology. Microorganisms in the soil can travel into groundwater supplies through cracks, fissures, and other pathways. Nitrates and nitrites from the nitrogen compounds in the soil can also enter the groundwater. From the underlying rocks radionuclides and heavy metals can enter the groundwater. There are areas with natural occurring arsenic, cadmium, chromium, lead, selenium and fluoride. While many natural contaminants such as iron, sulfate, and manganese are not considered serious health hazards, they can give drinking water an unpleasant taste, odor, or color.

Human activities can also introduce contaminants into thegroundwater. Bacteria and nitrates can be caused by human and animal waste. Improperly constructed and sealed wells can allow surface contamination to enter the well. Improperly maintained septic systems containing human waste and any chemical you flush down the drain, horses, and backyard poultry can contaminate the groundwater. Leaks from underground storage tanks, surface disposal of solvents, motor oil, paint, paint thinner, termite treatment or nearby or historic landfills or industrial operations can contaminate groundwater. A confining geological layer can protect groundwater from surface contaminants more effectively than a fractured rock system, and there is extremely limited natural protection in karst terrain. Though it is cost prohibitive to test for every potential contaminant, a broad baseline analysis should be performed before purchasing a home (and every few years). A bacteria test is not enough. The cheapest way to do this is a commercial product aimed at the private homeowner. One product I have used is the WaterCheck with Pesticides. This product covers 15 heavy metals, 5 inorganic chemicals, 5 physical factors (like hardness and pH), 4 trihalo methanes, 43 volatile organic chemicals (solvents), and 20 pesticides, herbicides and PCB’s. The analysis takes two weeks and so the contingency period must allow for that or a more expensive analysis must be used. Whatever analysis you use, make sure you use an EPA certified laboratory that is also certified in the State where the property is located.

All private wells should be have as a water-tight, vermin-proof well cap and a cement or bentonite grout seal between the borehole and the well casing to prevent surface contamination and bacteria from entering the well. In coal or gas country, a well should include a vent. Well water should be tested annually to ensure a safe drinking water supply for your family. The supply of water should be adequate. In our modern world household water demand is not spread evenly over the day. There are peak usage times driven by washing machines, dish washers, showers. An adequate water system must be able to yield enough water to satisfy peak demand. Look for a minimum of 10 gallons a minute from a modern drilled well to supply a household or a system with intermediate storage (remember in some instances the well itself can provide storage). To live comfortably with your well, your water system has to be able to deliver an entire day’s worth of clear uncontaminated water within a 90 minute window.