Your Plumbing System

A basic understanding can be a big help.

Even if you do not maintain your plumbing system, you can save time, water, inconvenience and money by understanding key items about your plumbing system, maintenance needs, etc. Please use the links below to get more information.

Protecting pipes from freezing: To protect pipes from freezing, you can close foundation vents and close or seal other openings and cracks in unheated areas such as crawlspaces.

Town of Chapel Hill's webpage on Who is Digging in My Yard? including information on installation of fiber by Google and AT&T.

Does OWASA evaluate or endorse companies which provide plumbing installation, maintenance or repair services?

Our customers receive offers from private companies regarding repair service agreements and we receive inquiries about these offers.Some of the companies offer “insurance” programs involving repairs to privately-owned water or sewer service pipes when needed in return for payment of monthly fees. We cannot evaluate private companies, but we encourage our customers to understand the scope, benefits and costs of service arrangements just as a customer would in considering whether to buy an extended warranty or a non-utility service contract.

Water pipe maintenance: which pipes are part of the public water system maintained by OWASA, and which are privately maintained?

Private sewer service pipes or "laterals": private maintenance responsibilities and the conditions in which OWASA may repair the part of a private sewer service pipe in a public street right-of-way.

Private water and sewer service pipes and construction in street right-of-way.Some reminders about private service pipes and construction in a street right-of-way

Does your property insurance cover damage from wastewater back-ups?: We encourage you to talk with your insurance agent about whether you have coverage for property damage due to wastewater back-ups. If not, you may wish to get information from your agent on the cost, benefits and scope of such coverage.

Shut Off Valve

Emergency shut-off valve: We encourage you to know the location of and to clearly mark the shut-off valve in your plumbing system, and to install a shut-off valve if one is not in place. A shut-off valve saves water and can help prevent property damage when there is a major water leak.

Pressure reducing valve (PRV): You can reduce the potential for leaks by installing a pressure reducing valve in your plumbing system if you do not already have one. Plumbing codes require a PRV if the pressure at the OWASA water line serving your building is over 80 pounds per square inch. An adjustable PRV can be used to lower water pressure and therefore conserve water.

The "clean-out" pipe and cap for a private sewer service line. Sewer service pipes or "laterals" should have a vertical clean-out pipe with a removable cap. The cap prevents stormwater and debris from getting into the lateral and then the public sewers.

Water Heater

Thermal expansion of water: When water is heated due to operation of a water heater, the water will expand if possible or pressure will increase in the plumbing system. Increased pressure may damage the emergency pressure relief valve in a water heater and/or cause leaks in pipes and fixtures. You can install a thermal expansion tank or a toilet tank fill valve with a pressure relief valve to relieve pressure from thermal expansion of water.

P-traps: A p-trap prevents gas in plumbing drains and sewer mains from rising into a house or other building. If a p-trap is empty due to lack of use of a drain or toilet and normal evaporation, you can pour water in the drain or flush the toilet to refill the p-trap.

For the public safety and health.

Backflow prevention devices are required for swimming pools, irrigation systems and various non-residential locations to prevent water in a private system from being drawn back into and potentially contaminating the public water system. For additional information:

Proper disposal of fat, oil and grease helps prevent wastewater overflows

Residents may dispose of routine amounts of fat and grease with household refuse, and can recycle used cooking oil at Orange County's household hazardous waste program on Eubanks Road on the north side of Chapel Hill. 

Businesses that produce waste fat, oil and grease are required to install and maintain grease traps. Waste grease that accumulates in a trap must be periodically removed and recycled.

For additional information: