Water-Testing Laboratories Key Terms

Understand the procedures of water-testing laboratories by knowing the key terms

By Kathryn Keep

Water-testing laboratories help keep our drinking water safe from bacteria and other pollutants. The Safe Drinking Water Act regulates the testing of public water supplies. Private well owners should also do routine testing. Here are a few of the most common tests that water-testing laboratories run:

1. The most general routine check done by a laboratory is for Coliform bacteria.

2. The pH of a water sample is a good measure, particularly for the lakes and rivers that are the original sources of drinking water.

3. It is also important to know the nitrate levels of your water supply.

Safe Drinking Water Act

The Safe Drinking Water Act (SDWA), created in 1974, protects public water supplies and their sources, such as lakes, rivers and reservoirs.
Try: The Environmental Protection Agency is your best source for specific information on the SDWA.

pH

The pH of a liquid is a measure of hydrogen ions represented by a number between zero and 14. A high pH means that a liquid is alkaline, and a low pH means it is acidic. Water should be near seven, which is neutral.
Try: Water on the Web offers more information and a scale comparing the pH of various liquids.

Coliform bacteria

Tests often find Coliform bacteria, which are generally harmless, in the environment, but their presence in a water supply can mean that something has compromised the water's safety. E. coli is a well-publicized strain of Coliform bacteria that can sometimes be dangerous.
Try: Washington State Department of Health provides more detailed information on what it can mean when tests find the bacteria in a water supply.

Nitrates

Unsafe levels of nitrates can occur from natural or man-made causes. Infants are particularly susceptible to the dangerous effects of nitrates.
Try: Illinois Department of Public Health discusses nitrates and their health effects.

Dissolved solids

Water-testing laboratories measure the total dissolved solids as more of an aesthetic than risk factor. Dissolved solids are not a health hazard, but they can cause unpleasant taste and a buildup in water heaters.
Try: Wilkes University Center for Environmental Quality offers information on measuring dissolved solids.

Private wells

Many people, especially those in rural areas, depend on private wells for their water supply. Private wells are not subject to the same regulations as public water supplies. While most wells are safe and clean, regular testing ensures the water is uncontaminated.
Try: The Centers for Disease Control and Prevention (CDC) offers extensive information on private wells and ensuring their safety.