The house has a well, should I buy it?

Private wells are not regulated in most states. Here in Virginia only the construction of a well is regulated, and that only went into effect in April 1992. Virginia is a "buyer beware" state. Any problem with a well, the groundwater or septic problems not detected by the buyer during the sale inspection process becomes the home buyer's problem. There is no legal recourse back to the seller. Well inspections are not part of the home inspections and testing for the presence or absence of coliform bacteria as required by mortgage lenders is not enough to know what you are buying.

Well owners are responsible for managing their water supply and may have little understanding of the quality and sustainability of their water supply.  Without testing a well might seem completely fine when in reality it is going dry and contaminated. Some contaminants are colorless, odorless and tasteless, while others effect taste and/or smell. They can all have health impacts.  Private wells can be safe and great tasting, or problematic and only research and testing before you buy a home with a well will enable you to tell the difference.

Start in the house. Look in the basement. If you see more equipment than a blue pressure tank 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.

my pressure tank

Home treatment is typically either Point of Use (POU) or Point of Entry (POE). POE treatment is at the point where water enters the home and provides whole home treatment. This type of treatment is generally more expensive because you are treating more water. It’s necessary, however, if you are treating for a contaminant that impacts health or renders the water aesthetically unusable (E. coli, hydrogen sulfate, radon come to mind). POU units are typically used to treat water for drinking and cooking at a specific tap or faucet. These systems are used to treat a contaminant that is a health risk if ingested, or that might cause taste issues. They only treat a portion of the water coming into your home. Look under the kitchen sink and attached to the faucet for POU systems. Household water treatment equipment has improved and changed over the years, but it does not fix water, it treats water and must be maintained and occasionally replaced. Often treating water for one problem creates other issues that must be ameliorated with additional equipment. Wells get old and sometimes need to be replaced, too. The life of a well is dependent on the geology and design. Rule of thumb is 30-50 years.

What you can live with in terms of water treatment equipment is really a personal decision once you understand the condition of the aquifer and the effectiveness of the treatment. When we bought our home I tested the heck out of the well, spending a lot of money. Still, I didn’t test for everything. I wanted to make sure that the well was drawing from a groundwater aquifer that was not contaminated. In addition, I wanted a well that was fine without any need for water treatment to address naturally occurring contaminants. I ended up testing for all the contaminants in the Safe Drinking Water Act and for a group of common pesticides because the home was on the site of a former farm.  There was no treatment equipment in the house, so I was able to do only one set of water tests. There are packages available from National Testing Laboratory and others to test your water.   If you are buying a home, you should test the raw, untreated water for all the primary and secondary contaminants in the Safe Drinking Water Act as well as nuisance substances like iron bacteria and tannins in certain geologies the water should be tested for both dissolved and total iron. The treated water should be checked for the same contaminants.

Water chemistry is a tough category to give rules of thumb. However, do not buy any home where E. Coli is present in the raw water. If there is E. coli, there is a failed septic system nearby (probably the home’s own) and it needs to be repaired and potentially the well replaced. That should all be taken care of before you purchase the home. You do not want to buy someone else’s problem.  Water with nitrate significantly above the background level (around 2 mg/L in northern Virginia) is also problematic and tends to be related to septic performance. 

The Safe Drinking Water Act maximum contaminant level (MCL) for nitrate in public drinking water supplies in the United States is 10 mg/L as nitrate-nitrogen (NO3-N). This concentration is slightly below the World Health Organization (WHO) guideline of 11.3 mg/L NO3-N. The regulatory limit for nitrate in public drinking water supplies was set to protect against infant methemoglobinemia, but other health effects were not considered. In 2018 Dr. Mary Ward was lead author on a review of more than 30 epidemiologic studies on drinking water nitrate and health outcomes. According to their study, the strongest evidence for a relationship between drinking water with elevated nitrate concentrations and adverse health outcomes (besides methemoglobinemia) is for colorectal cancer, thyroid disease, and neural tube defects. “Many of the studies observed increased health risks with ingestion of water nitrate levels that were below regulatory limits.” So, having nitrate concentrations below 10 mg/L is no protection against increased cancer risk or birth defects.

 The most common contamination problem for a well is an adjacent septic system. Most septic systems do not remove nitrate and studies performed in New York and North Carolina found that overall average density of traditional septic or alternative septic systems should not exceed one unit per 2-3 acres for an average size house to ensure water quality and recharge in groundwater supplies. Adequate dilution, soil filtration and time are necessary to ensure sustainable water quality. Note that nitrate was used as the tracer of contaminants, many traces of household cleaners, soaps, pharmaceuticals, and other contaminants present in septic waste water. You need to make sure that these issues have been corrected and the water quality issues resolved by the homeowner since total costs to address these problems can be tens of thousands of dollars.

You do not want to buy a home with very corrosive water because of the possibility of lead exposure from the well components ahead of any neutralizer you can install.   During periods of stagnation, in water that is corrosive (with a pH less than 6) a chemical redox reaction occurs that dissolves and leaches lead into the water. Lead present in well and plumbing components is leached into the water. This lead comes from brass fittings and galvanized pipe (which has a lead- zinc coating), and plumbing components produced before 2014 when "lead-free" fixtures could have up to 8% lead. In Virginia, the Blue Ridge, Piedmont and shallow wells in the Coastal Plain have a high risk for corrosive water and lead contamination in their water. U.S. Environmental Protection Agency Lead and Copper Rule action level for lead of 15 μg/L. However, there is no safe level of lead exposure, as even low water lead levels-those less than 5 μg/L- can increase a child's blood lead level. Most of the eastern seaboard states has areas at high risk for corrosive water.

In Virginia these are the rules for buying house with a well (and septic system).  These rules should 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
3. The well stabilized yield should be greater than or equal to 6 gallons/minute
4. The well should be drilled and more than 100 feet below grade (deep)
5. The well should be a 6 inch diameter pipe with a bolted cap sticking at least a foot out of the ground
6. Do not buy a home with a shared well
7. The well was drilled after April 1, 1992 (under the current regulations).
8. 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.
9. Health Department records show regular septic pump outs at least every 5 years. Annual inspections for alternative septic systems should be on file.
10. Don’t buy a house with a well in Karst terrain.
11. 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).
12. Don’t buy a house that found lead present in a flushed sample.
13. The well water must have a pH > 6.0
14. Draw a glass of water from the cold tap in a bathroom sink and taste it.