As there is no reservoir or Town water supply, Cornish is crucially dependent upon groundwater. Early farms and homes were sited near natural springs along Route 12A, Cornish Mills, and East Road, ensuring a plentiful and clean water supply.
Protecting groundwater is vital to maintaining a healthy ecosystem. According to the UNH Natural Resources Inventory guide, “At the global, national, regional and local levels, groundwater is the largest distributed store of freshwater and plays a central part in sustaining ecosystems and enabling human adaptation to climate variability and change. The strategic importance of groundwater for water and food security will probably intensify under climate change as more frequent and intense climate extremes (droughts and floods) increase variability in precipitation, soil moisture, and surface water. Protection of locally important aquifers by protecting the lands that overlie them is an important priority for maintaining adequate drinking water supplies into the future.” (Source: UNH Extension NRI)
Aquifers consist of saturated rock materials (e.g. gravel) that are permeable enough so that the water can move through them by gravity and be withdrawn from them by wells. An aquifer recharge area occurs where water is purified by losing its pollutants on the way through these materials. Large quantities of these water resources move slowly underground toward areas where they reappear in the form of ponds, wetlands, or springs. Aquifers and groundwater reservoirs are often used interchangeably.
There appear to be five major areas in Cornish that act as aquifers, holding and perhaps purifying groundwater. Each of these areas contain stratified drift (sand and silt) consisting of glacial outwash and recent stream deposits. (1) Along the Connecticut River from the Claremont line to Mill Brook at the base of Wellman’s Hill. (2) Along the Connecticut River in northwest Cornish to slightly east of Blow-Me-Down Brook and along the base of Dingleton Hill. (3) South Cornish after the junction of Whitewater and Redwater Brooks, where the brook swings north into Cornish again, crosses Route 120 and back into Claremont. (4) South Cornish, between Route 120 and East Pond is another area of large deposits. (5) Cornish Flat area north to the Plainfield line.
Only a small portion of these aquifers are within protected land — the most protected being around Blow-Me-Down Brook and St. Gaudens. Private land conservation is just one of the ways that we can help protect the aquifers against future development and sustain a source of freshwater for future generations.