Monitoring Barnegat Inlet, New Jersey, South Jetty Realignment: Fid-Bau Portal

Monitoring Barnegat Inlet, New Jersey, South Jetty Realignment

W. C. Seabergh / M. A. Cialone / J. W. McCormick / K. D. Watson / M. A. Chasten

The objective of this monitoring at Barnegat Inlet was to determine the response of the inlet system to a new south jetty completed in 1991 that essentially parallels the existing north jetty. Barnegat Inlet is accessed by a large number of commercial, sport fishing, and recreational vessels each year. An unstable navigation channel and numerous accidents and deaths at Barnegat Inlet led to the construction of the new south jetty. The response of the new south jetty and inlet system was determined by data collection and monitoring and compared with design predictions. This new knowledge will contribute to improved jetty and inlet system design guidance, enhance construction of rubble- mound jetties, and develop better maintenance techniques for tidal inlets. The monitoring plan evaluated four fundamental hypotheses of the project design objectives: (a) the new south jetty and new channel alignment will not adversely affect tidal hydraulic response or high tide level in the inlet by system (i.e., no flooding problem), and prototype hydraulic response will be as predicted by a previous physical model evaluation; (b)the new south jetty realignment will improve navigation safety by stabilizing the navigation channel and depth between the jetties and over the outer bar (ebb tidal shoal), and will eliminate dredging in these regions; (c) the new south jetty will be structurally stable; and (d) the jetty system realignment will not adversely affect up coast or down coast beaches.