ET-3D (2/17/05)
Environmental Targets And Priorities Overview: "As Is" Drinking Water Quality Situation

Ohio surface and ground water resources supply both public and private drinking water systems. The 1996 amendments to the Safe Drinking Water Act established the Source Water Assessment and Protection (SWAP) Program to address both surface and ground water sources of public drinking water. Private water systems (such as individual residential wells) also need protection from NPS impacts. Consequently, the NPS Plan 2005-2010 places greater emphasis on existing NPS impacts to drinking water quality and planning to eliminate future threats and problems.

Potential drinking water contamination is of particular concern in shallow sand and gravel aquifers, areas of karst limestone, and near surface fractured bedrock aquifers with thin to absent soils. For example, the 2004 drinking water contamination incident at South Bass Island (located in a sensitive fractured limestone aquifer) has been linked to improper wastewater management and disposal practices.

The following resources are currently available to characterize the "as is" situation for Ohio drinking water quality. By 2006, the Ohio EPA Integrated Water Quality Monitoring and Assessment Report will include data about surface drinking water source impairment.

Surface Water

  • Map of Surface Drinking Water Source Protection Areas;
  • Map showing priority areas where surface drinking water sources are impacted or threatened by nitrates and/or pesticides;
  • Case study about controlling NPS sources of pesticide contamination to a surface drinking water supply.

Ground Water

  • Ground Water Quality;
  • Map of priority ground water Drinking Water Source Protection Areas (public water systems with a high susceptibility to contamination and associated adverse water quality impacts);
  • Map showing ground water sources of drinking water that are impacted or threatened by nitrates;
  • Map showing sensitive aquifers that are vulnerable to NPS contamination (critical to protect for both public and private water supplies);
  • Case study about controlling sources of nitrate contamination to a ground water source of drinking water.