Ground-water resources of the Lamprey River basin, southeastern New Hampshire

Abstract

Communities in the Lamprey Riuer basin are experiencing the rapid population growth common to all communities in southeastern New Hampshire. The population of 15 towns within the basin increased about 40 percent from 1970 to 1980. This growth is expected to continue. Future water demand, both municipal and private, will increase in response to this population growth. By 2020, the demand may be 3 to 9 times greater than the present 3 Mgalld (million gallons per day) pumpage. Saturated sand and gravel deposits in the Lamprey and Piscassic River valleys and the area of Newmarket Plains are the most productive or potentially productive stratified-drift aquifers in the basin. Except for the aquifer at Newmarket Plains, induced infiltration of stream water would allow higher, but still modest, sustained yields to correctly placed wells. The aquifer near Deerfleld Fairgrounds has the potential to yield at least 0.06 Mgal/d. The aquifer in northwest Raymond may yield 1.7 Mgalld. A sustained withdrawal of 1 Mgalld is probable in the west Kpping area. The aquifer in central Kpping may already be fully developed. Further exploration for a confined aquifer beneath estuarine deposits in eastern Kpping is warranted. Pumpage from the Newmarket Plains aquifer could be increased to an estimated 0.6 Mgal/d. Systematic exploration for highly fractured zones in bedrock may allow siting of wells with relatively high yields. The chemical quality of ground water is generally suitable for domestic use. Recent and anticipated improvements in surface-water quality may result in little or no degradation of ground-water quality in those aquifers where pumpage results in induced infiltration. Chemical quality of ground water reflects highway deicing policies, and may reflect other land-use practices. Judicious land-use planning could protect the few extensive sand and gravel aquifers in this basin.