PREP Reports & Publications


The New Hampshire Estuaries Project (NHEP) is part of the U.S. Environmental Protection Agency’s National Estuary Program which is a joint local/state/federal program established under Section 320 of the Clean Water Act with the goal of protecting and enhancing nationally significant estuaries. The NHEP’s Comprehensive Conservation and Management Plan for New Hampshire’s estuaries was completed in 2000 and implementation is ongoing. The Management Plan outlines key issues related to management of New Hampshire’s estuaries and proposes strategies that are expected to collectively preserve and protect the state’s estuarine resources. The coastal watershed for the NHEP drains into two major estuary systems: the Great Bay Estuary and Hampton-Seabrook Estuary (Figure 1). There is also a small portion of the coastal watershed which drains directly to the Atlantic coast near Rye Harbor. The drainage area for the NHEP coastal watershed is 2,812.47 km2 [1,085.90 mi2]. The watershed boundaries and hydrology for the Great Bay Estuary and Hampton-Seabrook Estuary are shown in Figures 2 and 3. Detailed maps (1:24,000 scale) of the watershed and tidal waters boundaries used for this study are documented in an Appendix. The purpose of this report is to summarize the available hydrologic information for the Great Bay Estuary and Hampton-Seabrook Estuary. Estuary classification documents have been produced by Short (1992) and Jones (2000). UNH researchers have developed hydrologic models for the Great Bay Estuary (Brown and Arellano, 1980; Swift and Brown, 1983; Bilgili et al., 2005). Additional information has been created for licensing and regulatory reasons (e.g., PSNH, 1977). The information in these reports has been compiled and cross-checked against geographic databases and summarized in this report to provide accessible, consistent, and credible data. The values presented in this report will be used for all NHEP reporting and should be used for any national databases for estuarine classifications.


Piscataqua Region Estuaries Partnership

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New Hampshire Estuaries Project

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