Water Quality

NGWA Well Owners Guide

This handout provides instructions for disinfecting your water system, which includes both the well that has a submersible pump and the associated water distribution system. These instructions can be used for a single family home or businesses such as resorts and campgrounds. Disinfection can eliminate or reduce harmful bacteria, viruses, or other microorganisms that may be found in your drinking water.

What is a bladder pressure tank? It is a type of tank containing pressurized air and water separated by a membrane (bladder) and pre-charged with air at the factory. On average, a bladder pressure tank lasts 5–7 years. Please refer to Pressure Relief Valves on Pressure Tanks (331-429), a one-page illustrated tech tip. It explains design requirements, how pressure relief valves protect pressure tanks, and how to ensure pressure relief valves are approved and installed properly.

Heavy metals such as lead, copper, cadmium, arsenic, and mercury may be present in water supplies for a variety of reasons. Lead and copper most commonly leach into water supplies through corrosion of household plumbing fixtures, pipes, fittings, and solder, and cadmium contamination may occur as a result of impurities in the zinc of galvanized pipes or fittings. Water supplies that are corrosive are more likely to leach lead, copper, and possibly cadmium from pipes and fittings, if these metals are present in plumbing systems. Some factors that can indicate corrosive water include low pH, high temperature, low total dissolved solids content, and high amounts of dissolved oxygen or carbon dioxide.

Hard water contains high levels of calcium and magnesium ions. These ions, among others, are naturally dissolved into groundwater as it comes in contact with soluble limestone and other rocks and minerals. While consuming hard water does not present a health risk, it may cause aesthetic or nuisance problems such as bitter taste or mineral deposits (scale) on dishes, utensils, and plumbing fixtures. Hard water can also reduce the efficiency and life span of water heaters.

Water Treatment

Until recently, the point-of-use water treatment industry focused on improving the aesthetic quality of drinking water. The industry has lately been thrust into the forefront of treatment of contaminated drinking waters that pose a serious health hazard. The response has been a plethora of companies and products promising to render the consumer’s drinking water safe and contaminant free. The individual is left to sift through advertising claims and technical data to select the appropriate treatment method.

Water is often called the universal solvent. As water moves underground or over land, it dissolves a variety of compounds including minerals, salts, and organic compounds. The concentration of “total dissolved solids” (TDS) in a water sample is a measure of the dissolved compounds in the water small enough to pass through a 2-micrometer sieve. For comparison, one human hair is approximately 100 micrometers in diameter. A TDS test measures the amount, but does not identify the individual compounds or their sources.

Sulfate (SO4) is a naturally occurring mineral that can be dissolved into groundwater. Hydrogen sulfide (H2S) is a colorless gas that gives water a distinctive sulfur or “rotten egg” smell and taste, which may be especially noticeable in hot water. The presence of low levels of hydrogen sulfide in household water is not a health hazard, but hydrogen sulfide can make water more corrosive, which can result in leaching of metals present in the plumbing system. The offensive odor and other nuisance problems associated with hydrogen sulfide may make treatment desirable.

Knowing the amount of sodium in your drinking water is important for your health, especially if you have high blood pressure. Sodium is an essential mineral for maintaining a healthy fluid balance and is important for brain function and muscle contractions but consuming too much sodium can elevate your blood pressure.