The Environmental Protection Agency developed the Ground Water Rule (40 CFR Parts 9, 141 and 142) to provide for increased protection against microbial pathogens in public water systems that use ground water sources. This final rule is in accordance with the Safe Drinking Water Act. The final rule became effective on January 8, 2007. The compliance date for public water systems, unless otherwise noted, for rule requirements is December 1, 2009.

The Ground Water Rule establishes a risk-targeted approach for ground water systems that are susceptible to fecal contamination, instead of requiring disinfection for all ground water systems. The occurrence of fecal indicators in a drinking water supply is an indication of the potential presence of microbial pathogens that may pose a threat to public health. This rule requires ground water systems that are at risk of fecal contamination to take corrective action to reduce potential cases of illness and death from exposure to waterborne microbial pathogens.

Groundwater public water supply systems that are currently considering upgrades or improvements to their sources of supply, storage facilities, or treatment systems should pay particular attention to the requirements of the GWR and assess the Rule’s potential impact on the design and configuration of any proposed upgrades. Please also note that the GWR requires that all groundwater systems have the capability of sampling the raw water at each of their groundwater sources before any treatment as of December 1, 2009.


Public water systems that have a department-approved Source Water Fecal Indicator Monitoring Plan under RCSA §19-13-B102(e)(12)(I) are not subject to the assessment source water monitoring requirements of RCSA §19-13-B102(e)(12)(D)(iii). A Source Water Fecal Indicator Monitoring Plan identifies the ground water source or sources that the water system will sample for E. coli analysis, the frequency of sampling and the sampling location. Complete the public water system Fecal Indicator Assessment Monitoring Plan and submit the completed form to the Department for review.