Publication Date
4-9-2007
Abstract
Covering nearly 200 square miles and storing an estimated 500 billion gallons of water, the Plymouth-Carver Aquifer (PCA) in southeastern Massachusetts is one of the largest aquifers in New England. It provides abundant drinking water, supports cranberry cultivation, feeds hundreds of ponds, and maintains flow to streams. The numerous coastal plain ponds support a variety of globally rare species. In recognition of the importance of the PCA to the coastal plain ponds, the Town of Plymouth partnered with The Nature Conservancy (TNC) and hired the Horsley Witten Group to identify potential water supply locations that minimize potential ecological impacts to critical water resources while providing quality water supply capacity into the distant future. The project was a planning-level analysis that included a GIS evaluation to identify potential land use conflicts, hydrogeologic modeling to identify potential impacts to nearby water resources, and a water supply development plan. Twenty-one potential well sites were identified with favorable geology, maximum separation from sensitive water resources, and minimally developed upgradient contributing areas. Those sites were prioritized based upon proximity to existing water system infrastructure and areas of projected water system expansion. Those sites closest to sensitive water resources were further evaluated using a groundwater model to delineate the contributing areas to subject wells and ponds, and to identify potential drawdown impacts to water resources from the operation of those wells. The Town is currently conducting detailed field-based investigations of some of the more promising sites from the study. By working cooperatively with TNC from the project inception, and by taking a comprehensive approach to water supply development, the Town is likely to enjoy a simplified permitting process as selected individual sites are developed. In addition, the identification of numerous potential water supply locations will help the Town protect these valuable resources for future needs.