The United States Environmental Protection Agency (EPA) recognized the danger that lead poses in the drinking water and in 1991 issued the Lead & Copper Rule which mandated that water systems adjust their water chemistry to control corrosion, and therefore limit lead leaching into the water.

As required, we treat our drinking water specifically to minimize the amount of lead that may leach into the drinking water and undergo a testing program to ensure that the treatment is effective. Monitoring has shown that the program is effective in minimizing lead levels in home tap water.

Specifically, the lead corrosion control treatment consists of:

  • Adding lime and sodium hydroxide to the water to increase the water’s pH levels so that the water is minimally corrosive to lead
  • The chlorine disinfectant added provides protection
  • These two water chemistry adjustments work together to form a protective film covering surfaces containing lead
  • This film then minimizes lead that can enter the water
  • We then monitor the effectiveness of this strategy as per the regulation

The vast majority of water systems in the US have installed corrosion control systems. However, the EPA has seen that sources of lead still exist in water systems. As long as these sources exist, there is a risk from lead and these sources can be a potential risk; therefore, removing the sources (lead service lines) from service is the most effective way to permanently reduce the risk of lead exposure.

The EPA has a guide (PDF - 568KB) for water customers about lead in drinking water and how consumers can reduce their risk of lead exposure as well as a web page about the Lead and Copper Rule.

Last Edited: November 20, 2019