THE NEW HAMPSHIRE GROUND-WATER MONITORING NETWORK: LIMITATIONS OF MONITORING BY PROXY

The state of New Hampshire currently measures water levels in 25 wells located throughout the state on a monthly basis. Water-level data is shared with the USGS District office, which posts statistical summaries on their web site. These wells comprise the state’s ground water monitoring network, although the network is not statutorily established, and no funds are appropriated to support its operation and maintenance. The network was created by enlisting wells that were orphaned after the completion of a USGS/State cooperative project to map stratified drift aquifers. Thus, their depth, design, and placement is inherently biased for evaluating shallow surficial aquifers. The wells were drilled to obtain subsurface control, and for conducting tests to determine hydraulic parameters of the sand and gravel deposits. While access to the wells after the project provided a compound use of the existing well infrastructure, their functionality is limited for use as a water management tool, and for developing policy perspectives. For example, while approximately 14 percent of New Hampshire’s land area is covered by stratified drift, only 4 percent of new private water wells are drilled into surficial aquifers. Contrarily, 96 percent of all wells are drilled into the fractured bedrock aquifer, but only one of the state’s 25 monitoring wells monitors this zone. Moreover, the average depth of all bedrock wells in the state is 337.9 feet (n=78,319) whereas their depth of the state’s lone bedrock monitoring well is 102.7 feet. Clearly, the state is using a lone apple tree to interpret what is occurring in an orange grove. Although inadequate, the sheer existence of a monitoring network gives many policy officials and the public a false sense of security. The New Hampshire Geological Survey is currently leading efforts to obtain a legislative appropriation for a capital infrastructure improvement to drill 24 bedrock wells to complement the existing surficial wells. The additional wells, as well as the use of real-time measuring and recording instrumentation, will aid in the creation of a more representative statewide network. However, this effort will be hampered by policy maker’s lack of scientific understanding regarding the shortcomings of the current network, and statewide fiscal constraints.