Drinking water treatment and regulation

Who sets the standards for the quality and safety of drinking water?

Both Federal and State agencies set the standards. In accordance with the Federal Safe Drinking Water Act (SDWA), the U.S. Environmental Protection Agency (EPA) issues national standards for the quality of drinking water and how it is tested. For more information, please visit EPA’s water quality website. The State of North Carolina sets some additional drinking water standards related to water quality testing procedures and regulatory limits.  State regulations can only be more stringent that then Federal regulations.

Who tests the quality of OWASA’s water? How?

The staff at our Jones Ferry Road Water Treatment Plant Laboratory, which is approved or “certified” by the State, monitors our drinking water quality by doing about 50,000 tests each year.

Using state-of-the-art equipment and instruments, our laboratory staff tests for more than 100 substances in drinking water, a small number of which are present at detectable levels. The results of these analyses are published in our annual Water Quality Report Card, which is distributed throughout the OWASA service area in Chapel Hill-Carrboro each spring.

Our Laboratory staff does most of the water testing required by State and Federal regulations. Private laboratories approved by the State do some specialized testing for OWASA.

In addition to testing our drinking water, we monitor the water quality in our reservoirs, as water goes through the treatment process, and as water moves through our “distribution system” of more than 390 miles of public water pipes in the Carrboro-Chapel Hill community. 

Is a home filter needed for OWASA drinking water?

OWASA does not recommend removing disinfectants, except for special uses including dialysis and in fish/amphibian tanks, because disinfectants kill bacteria.  Maintaining a disinfectant residual in our water mains and your home plumbing helps prevent bacterial regrowth such as the formation of bio-films.  Please visit our webpage on drinking water treatment and water disinfection for more information.

A home filter may be necessary if you have a weak immune system, other special medical conditions (such as a need to do home dialysis), allergies, or sensitivities that you can address with additional filteringFor home dialysis or other specialized medical uses, please follow the advice of health care providers and medical equipment manufacturers regarding water filtration or treatment.

Otherwise, OWASA customers do not need to treat their drinking water at home to make it safe. Certain home water treatment units can improve water's taste, or provide an extra margin of safety for people with severely compromised immune systems or other people who may have special needs.  For more information about water filters see the EPA Filtration Facts brochure, NSF International’s guide to drinking water treatment unit standards, and NSF International’s searchable database of certified drinking water treatment units and water filters.

If you own or plan to buy home water treatment unit, we recommend carefully researching the product so that you will understand its capabilities, limitations, benefits and ongoing costs for filter replacement, maintenance, etc. Please follow the manufacturer's instructions for operation and maintenance, and especially those for changing the filter on a regular basis.

Please note: if a filter is not changed regularly, it may stop working as intended and could become a source of bacterial growth or other contamination.

What should I do if I want OWASA to test the OWASA drinking water in my home or business?

Please contact the OWASA Laboratory Staff at (919) 537-4228 or send an e-mail to WTPLaboratory@owasa.org to schedule an appointment with a Laboratory Analyst who will come to your home or business to get a water sample. Typically, we schedule water sampling at customers’ homes or businesses on Mondays through Thursdays between 10 AM and 12 PM.  We test the pH, chlorine, turbidity (or clarity) of our water, and for bacteriological indicators.

We also provide lead and copper testing of our water for our customers.  To request a lead and copper sample kit please contact the Laboratory Staff at (919) 537-4228 or send an email to WTPLaboratory@owasa.org

There are no fees for these services.

Who tests water from private wells?

If you live in Orange County and wish to have your well water tested, please contact the Wells Division of the Orange County Health Department at 919-245-2360, call 967-9251 and ask for the Wells Division, or visit their website for more information.