Lead in Drinking Water
Basic Lead Information
Lead is a common, natural metal that is found throughout the environment; however it rarely occurs naturally in surface water supplies such as lakes and rivers. Lead enters drinking water primarily as a result of corrosion of materials containing lead used in household plumbing. This is particularly the case with older homes. Piping containing lead is likely to be found only in homes built before 1930. Copper piping took the place of lead piping, but lead based solder was still used until banned by North Carolina in 1985. Brass materials, containing less than 8% lead, are now used in almost 100% of all residential, commercial, and municipal water distribution systems. This action has significantly reduced the incidence of lead in drinking water.
The city has taken additional steps to reduce the leaching of lead into tap water by adding a corrosion inhibitor to drinking water. This effective corrosion control program has been in place since the 1970s.
Lead may dissolve into tap water when it stands for periods of several hours in the plumbing of some older homes. These are homes that have copper pipes with lead solder, lead pipes, or lead service lines. The EPA has determined that houses built between 1982 and 1987 meeting the above conditions may have an elevated risk of lead in drinking water. Please note that lead service lines have not been used for decades; occasionally when they are discovered, they are replaced by City Water and Sewer Maintenance staff.
The City of Durham is required to test for lead and copper every 3 years. Durham maintains a sampling pool of more than 200 homes throughout Durham which were constructed between 1983 and 1985 for triennial tests. During a testing year, samples are collected from the volunteer pool and analyzed to ensure on-going compliance with established levels. In these sampling events, a first draw sample is collected after the water has stood unused in the plumbing for at least 6 hours - usually overnight.
In order to meet EPA standards, sample results are ranked from lowest (in milligrams per liter) to highest. The concentration of the sample at the 90th percentile must be below the EPA Action Level - 0.015 mg/l for lead and 1.3 mg/l for copper. Durham strives to manage the water system so that all samples are below the detection levels. Durham implements the EPA’s updated sample collection protocol.
In most cases, customers can reduce or eliminate the chance of lead exposure in tap water by following these guidelines:
- Run cold water from your tap for about 1 to 2 minutes before using it for drinking or cooking any time the water in the faucet has gone unused for more than 6 hours.
- Flush each faucet individually. To conserve water, use the flushed water for non-consumption purposes such as watering plants or washing dishes. Fill a few bottles of water after the tap has been flushed to avoid having to flush the taps daily.
- Never cook with or drink water from the hot water tap. Hot water dissolves lead more quickly than cold water. Never use hot tap water to make baby formula or cereal; draw cold water from the tap and heat it on the stove or in the microwave.
- Periodically remove loose debris from the plumbing materials by removing the faucet strainers from all taps and running the water for 3 to 5 minutes.
Having Your Tap Water Tested
If you are a City of Durham water customer, your home was built before 1986, and you are concerned there may be lead in your home's plumbing, you can request to have your water tested for lead. To request a free sample kit, contact Durham One Call at 919-560-1200.
questions about lead exposure
The Durham County Department of Public Health manages the Lead Education and Assessment Program (LEAP), which offers services to increase lead education and awareness. LEAP's website has helpful information about ways you can protect your family from possible lead exposure. Visit their website, email their staff, or call 919-560-4842 for further information and assistance.