New EPA Rule Targets Utilities That Provide Drinking Water From Underground Sources

On Oct. 12, EPA issued a new rule to provide for increased protection against microbial pathogens in public water systems that use groundwater sources.

According to EPA, the Ground Water Rule (GWR) will protect more than 100 million Americans by requiring identification of deficiencies in water systems that could lead to contamination and corrective actions to reduce risk from any identified deficiencies. The GWR will apply to public water systems that serve groundwater. The rule also applies to any system that mixes surface water and groundwater if the groundwater is added directly to the distribution system and provided to consumers without treatment.

"The Bush administration's Ground Water Rule boosts drinking water purity and public health security," said Benjamin H. Grumbles, assistant administrator for Water. "These first-ever standards will help communities prevent, detect and correct tainted groundwater problems so citizens continue to have clean and affordable drinking water."

The risk-targeting strategy incorporated in the rule provides for:

  • Regular sanitary surveys of public water systems to look for significant deficiencies in key operational areas.
  • Triggered source-water monitoring when a system that does not sufficiently disinfect drinking water identifies a positive sample during its regular monitoring to comply with existing rules.
  • Implementation of corrective actions by groundwater systems with a significant deficiency or evidence of source-water fecal contamination.
  • Compliance monitoring for systems that are sufficiently treating drinking water to ensure effective removal of pathogens.

A ground water system is subject to triggered source-water monitoring if its treatment methods don't already remove 99.99 percent of viruses. Systems must begin to comply with the new requirements by Dec. 1, 2009.

Contaminants in question are pathogenic viruses -- such as rotavirus, echoviruses and noroviruses -- and pathogenic bacteria, including E. coli, salmonella, and shigella. Utilities will be required to look for and correct deficiencies in their operations to prevent contamination from these pathogens.

Microbial contaminants can cause gastroenteritis or, in rare cases, serious illnesses such as meningitis, hepatitis or myocarditis. The symptoms can range from mild to moderate cases lasting only a few days to more severe infections that can last several weeks and may result in death for those with weakened immune systems. The new groundwater rule will reduce the risk of these illnesses, EPA officials said.

Fecal contamination can reach groundwater sources, including drinking water wells, from failed septic systems, leaking sewer lines, and by passing through the soil and large cracks in the ground. Fecal contamination from the surface may also get into a drinking-water well along its casing or through cracks if the well is not properly constructed, protected or maintained.

The U.S. Centers for Disease Control and Prevention reports that, between 1991 and 2000, groundwater systems were associated with 68 outbreaks that caused 10,926 illnesses. Contaminated source water was the cause of 79 percent of the outbreaks in ground water systems.

More information about the Ground Water Rule can be found at http://www.epa.gov/safewater/disinfection/gwr.