Updating a Method to Estimate Probable High Groundwater Levels in Massachusetts

Science Center Objects

Periodic high groundwater levels are a major cause of septic system-failures, wet basements, and other problems for suburban and rural residents in Massachusetts. High groundwater-level estimates for installation of on-site septic systems are mandated by State regulations.

A method for estimation of probable high groundwater levels at unmonitored sites of interest (commonly referred to as the “Frimpter” method) was developed by USGS to meet this need (Frimpter, 1981). The water-level records used by the method have not been updated in several decades, and likely do not reflect current hydrologic conditions.  Therefore, the main purpose of the project is to update the water-level data used by the method. The specific objectives are to:

  • Update the groundwater-level statistics required by the method to the present (2018), including data from the current, expanded well network.
  • Analyze potential differences in calculated groundwater-level ranges from monthly and continuously recording wells.
  • Analyze the transferability of groundwater-level estimates among well sites, to promote the improved selection of index wells required by the method.
  • Analyze potential trends in annual water-level ranges over the newly extended period of record.