County Summaries of Pennsylvania Groundwater Well and Spring Data

There are over one million rural homes and farms that use a private water well or spring in Pennsylvania but there are no statewide regulations requiring testing of these drinking water supplies. Testing is the voluntary responsibility of the homeowner. Penn State Extension has created resources to help answer questions about how, where, and when to test drinking water from private water supplies. But one of the most common questions is WHAT to test for? Online data available from Penn State can help to answer this question.

Each year, thousands of water well and spring owners across Pennsylvania submit samples of their drinking water for analysis at the Penn State Agricultural Analytical Services Laboratory (AASL). The laboratory can test for dozens of water quality parameters and offers numerous water test packages for well and spring owners.

The laboratory keeps an updated summary of water samples received from each county on their Drinking Water Test Summaries by County website. The summary for each county includes the number of samples along with the minimum, maximum and average concentration for each water quality parameter. Most importantly, the percentage of samples that fail drinking water standards are also provided for each parameter. Each summary includes data for total coliform bacteria, E. coli bacteria, pH, total dissolved solids, corrosivity index, hardness, nitrate-nitrogen, chloride, sulfate, aluminum, arsenic, barium, cadmium, calcium, chromium, copper, lead (first-draw and running water), magnesium, manganese, mercury, nickel, sodium and zinc.

The statewide and county summaries, which are updated each year, provide a valuable tool for private water well and spring owners who are trying to determine which water pollutants are most common in their area and, thus, most important for testing in their drinking water supply.