Quality Water for Idaho Current Information Series No. 873

Should You Have Your Water Tested?
Whether to have your water tested is a serious question that concerns your health and that of your family. Your water should be safe to drink and acceptable for all other household uses. Contaminated water can cause illness and perhaps even death. In addition, a variety of less serious problems such as bad taste, off-color, odor and staining of clothes or fixtures are symptoms of water quality problems.

Even water that appears problem-free and crystal clear may not be safe or acceptable. Even so, not all people need to test their water. Testing for all possible contaminants is impractical and unnecessary.

When Should You Test Your Water?
Whether you have a public or private water supply, you should have your water tested if the following situations arise:

Public vs. Private Water Supplies
Many homeowners get water simply by turning on the faucet and making a monthly payment to a municipal or other local water system. They use public water supplies in which individual households are connected to the same water system. Public systems draw water from rivers, reservoirs, springs and groundwater wells.

In private systems, individuals or individual households provide their own systems. Most private drinking water comes from wells, sometimes from springs and ponds.

If your water comes from a public water system, your water is tested regularly for contaminants that are covered by federal and state standards. These contaminants include pathogens, radioactive elements and certain toxic chemicals. However, some public water supplies may have water quality problems caused by inadequate treatment facilities or distribution systems. Some rural water supply districts do not have enough money to hire trained specialists or to comply immediately with expanding government requirements. In addition, corrosive water or deteriorating household pipes may add contaminants to drinking water after it enters the house.

If your drinking water comes from your own well, you alone are responsible for ensuring its safety. Routine testing for a few of the most common contaminants is highly recommended. Even if your water supply currently is pure and safe, regular testing can be valuable because it establishes a record of water quality. This record can be helpful in solving any future problems and in establishing or assessing damages to your water supply.

Testing Private Water Supplies
Routine Tests -- The following testing frequencies are guidelines. Test more often if you suspect a problem with the quality of your water supply.

• Once each year, test for coliform bacteria, nitrate, pH and total dissolved solids (TDS). The best times to test for these contaminants are during spring or summer following a rainy period. These tests also should be conducted after repairing or replacing an old well or pipes and after installing a new pump.
• Every 3 years, test for sulfate, chloride, iron, manganese, lead, hardness and corrosion index.
• If a new baby is expected in the household, it is a good idea to test for nitrate in the early months of pregnancy, before bringing the infant home and again during the first 6 months of the baby's life.

Collecting Test Samples
Most testing laboratories or services provide their own sample containers. Use the containers and carefully follow the laboratory's instructions for collecting, preserving and handling water samples. Samples for coliform bacteria testing must be collected in sterile containers under sterile conditions. Some collection procedures call for water to run from an inside tap for several minutes before you fill the sample containers. Other instructions ask you to collect samples in the morning, after water has been confined in the pipes overnight. Samples should arrive at a laboratory within 24 hours of collection.

Laboratories may sometimes send a trained technician to collect the sample or to analyze the sample in your home. Ask if this service is available. You may obtain better samples and therefore more reliable test results.

Record all your water test results as a reference for future testing. Even slight changes in contaminant concentrations are good indicators of new water problems. By comparing recent test results with past results, you may discover you need a change in treatment or that a treatment device is working poorly.

Testing Services

• Public water supply systems are tested regularly for primary contaminants, monitored for levels of sodium and certain unregulated chemical contaminants and examined for corrosion in the water distribution system. They will provide water quality reports upon request.
• Private testing laboratories are listed in the yellow pages of the telephone book. Make sure they are certified by your state health department.
• County and state health laboratories, departments of health and local hospital laboratories often provide water testing services.
• Water treatment companies and plumbing supply stores may offer certain free tests in your home.
• Local engineering firms may test water for certain contaminants.
• The University of Idaho offers water testing services.
• Be wary of companies offering "free home water testing." Some of them may be interested only in selling you a water treatment device, whether or not you need it.

The Authors -- Ernestine Porter is Extension textiles and clothing specialist, Roy Taylor is Extension agricultural engineer and Robert L. Mahler is soil scientist and Extension water quality coordinator, all in the University of Idaho College of Agriculture, Moscow.

This publication is one of a series on water quality issues produced by the University of Idaho Cooperative Extension System for the people of Idaho. The material is based upon work supported by the U.S. Department of Agriculture, Extension Service, under special project number 90-EWQUI-1-9216.

Issued in furtherance of cooperative extension work in agriculture and home economics, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, LeRoy D. Luft, Director of Cooperative Extension System, University of Idaho, Moscow, Idaho 83844. The University of Idaho provides equal opportunity in education and employment on the basis of race, color, religion, national origin, gender, age, disability, or status as a Vietnam-era veteran, as required by state and federal laws.

8M 9-90, 5M 1-91 (reprint) Printed with special grant funds from USDA

Comments to author: karenl@uidaho.edu

All contents copyright © 1997-2002.
College of Agricultural and Life Sciences, University of Idaho.
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Revised: January 3, 2002

URL: http://www.uidaho.edu/wq/wqpubs/cis873.html