A well should be a 6 inch diameter pipe with a bolted cap sticking about a foot or more above the ground surface. What I have described is a drilled well there is also dug and bored wells. Those types of wells fail sooner, are prone to go dry during droughts and because they are shallow (less than 40 feet deep) are far more subject to pollution in our modern world. Drilled wells are more than 40 feet deep, typically more than 100. In Prince William County most drilled wells are between 150 and 450 feet below ground surface. Since 1979 in Prince William County and 1992 in Virginia as a whole well drillers are required to file a drilling log with the county and comply with drilling regulations.
Both wells and the mechanical components of a well have a limited life. Someday the well components and well its self will have to be replaced- plan and budget for it because you cannot live without a water supply. While many wells will last decades, it is reported by the groundwater association 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. Also, over time the amount of water a well yields can decrease. That can be caused by the water table falling due to extended drought, increased use or building in the recharge area. Mineral encrustation and reducing bacteria buildup can cause plugging of holes in the well casing, well screen or the filling of openings in the geologic formation itself.
To keep the water flowing to your home you need to maintain your well and the equipment and occasionally replace components. This starts with regular well inspections. Start by walking out and looking at your well. The well should have a sanitary, sealed well cap, firmly seated and bolted to prevent contamination from insects from entering the well. Next make sure the soil is packed so that it slopes away from your well to prevent surface water from pooling around the casing, which can allow storm water to seep into your well. Sooner or later all well grouting fails and sloping the soil slows this down and helps to keep the surface water away from the well casing. Look to see if your well casing is rusted through, if you have an old steel casing, it will happen someday.
Test your well once a year for at least total coliform bacteria. While coliform bacteria are not a health threat itself, it is used to indicate other bacteria that may be present and identify that a well is not properly sealed from surface bacteria. The Virginia Rural Household Water Quality Program recommends that ever three years you test your well for at least coliform bacteria, E coli, pH, total dissolved solids (TDS), nitrate, and other contaminants of local concern. For me every one of the contaminants of concern is reducing bacteria. Usually called iron bacteria, it will also reduce manganese and sulfate creating a biofilm in the well, slime on the flappers in the toilet tanks and throw off my alternative septic system.
Elevated levels of iron, manganese and sulfate in groundwater are an ideal media for iron bacteria to grow. Iron bacteria are present in soils and surface water in this area of Virginia and in many parts of the country. Iron bacteria can be introduced into a well during drilling, repair, or service if tools, equipment, or devices used during well drilling or pump servicing were not properly disinfected. It is believed that the bacteria must be introduced into the aquifer and cannot infect the water without human help. There are tests that can look for micro-biologicals. National Testing Laboratories sells a mail in test for $40. You may want to take a look at all their products.
Some health departments in parts of the country that are also iron rich recommend chlorinating the well once a year or anytime it has been opened or serviced as a method of prevention and control of the bacteria. Elimination of iron bacteria once a well is heavily infested can be extremely difficult. Normal treatment for a problem such as this would be to chlorine “shock,” but iron bacteria can be particularly persistent and chlorine treatment of the well may be only partly effective. I chlorinate my well every couple years to address the iron bacteria and noticed that I like the quality of the water. I am essentially flushing the water system to remove residue and buildup from the system.
A new program that the Virginia Rural Household Water Quality Program is trying to launch is a professional well maintenance checkup. I have not tried a checkup from a participating Well Driller, yet, but a well maintenance check-up should include four components:
- A flow test to determine system well output and water level before and during pumping. (This is made possible by sounders and flow meters.)
- Check amp load, grounding, and line voltage on the pump. Check the pressure tank and pressure switch contact.
- The well equipment should be inspect to assure that it is sanitary and meets local code requirements.
- The water should be tested for safety and quality- iron, manganese, nitrate, lead, arsenic, fluoride, sulfate, pH, total dissolved solids, hardness, sodium, copper, total coliform bacteria and E. coli bacteria, and anything else of local concern.
You need to have a clear understanding of how your well and water system work to ensure that you system is properly maintained and operated. Do not ever buy water treatment equipment until you have determined by testing that it is necessary and you understand potential impacts and other treatment options. So far, I have no water treatment equipment on my system. As this posts I am really outside flushing my well from yesterday’s adventure in disinfection. I will write about that later, and in a few weeks or months I will know if I need to install a water disinfection system or if shock chlorination has solved my problem.