US EPA Notes Successes in Reducing Perchlorate in Drinking Water

EPA Notes Successes in Reducing Perchlorate in Drinking Water

Contact Information:

EPA Press Office ([email protected])


WASHINGTON (May 14, 2020) — Today, the U.S. Environmental Protection Agency (EPA) is releasing information on reductions of perchlorate in drinking water due to actions that its partners and the agency have taken to mitigate this contaminant and protect public health. The agency is also providing information for drinking water utilities on perchlorate.

“Because of steps that EPA, states and public water systems have taken to identify, monitor and mitigate perchlorate, the levels have decreased in drinking water” said EPA Administrator Andrew Wheeler. “This success demonstrates that EPA and states are working together to lead the world in providing safe drinking water to all Americans.”

Since EPA made a determination to regulate perchlorate in drinking water in 2011, meaningful reductions have occurred due to actions taken by EPA, states and public water systems. The main factors contributing to the decrease in perchlorate levels include:

  • Improved procedures for storage and handling of hypochlorite solutions used as drinking water disinfectants.
  • Remediation activities at 60 Superfund sites to address perchlorate.
  • Drinking water regulations for perchlorate in Massachusetts and California.
  • Federal and state remediation activities at perchlorate contaminated sites, particularly the ongoing remediation efforts in the state of Nevada to address perchlorate contamination in groundwater adjacent to the lower Colorado River upstream of Lake Mead.

EPA remains committed to continuing to work with states and public water systems and is providing information to water systems on addressing perchlorate in drinking water. For more information on the declining levels of perchlorate in drinking water and information for drinking water utilities:


On June 26, 2019, EPA published the notice of proposed rulemaking seeking public comment on a range of options regarding the regulation of perchlorate in public drinking water systems. EPA is developing a final action that reflects comments received on the agency’s proposal and will be issued this June. For more information about EPA’s proposal, see

Perchlorate is commonly used in solid rocket propellants, munitions, fireworks, airbag initiators for vehicles, matches, and signal flares. Perchlorate may occur naturally, particularly in arid regions such as the southwestern U.S., and can be found as a byproduct in hypochlorite solutions used for treating drinking water and nitrate salts used to produce fertilizers, explosives, and other products.