This report details the results of the 1989 Pre-Existing Conditions Topographic and Bathymetric Survey at Terrapin Nature Park and the follow-up 2004 Topographic and Bathymetric Survey after the Chesapeake Bay had suffered sever impact of Hurricane Isabel in September 2003 which damaged significant areas with high winds, extremely high tides and storm surges.
The results of our 2004 resurvey of the Beach Prisms installation at Terrapin Nature area found that:
- The Beach Prisms installation had exhibited minimum movement from the original placement in 1989 even after suffering numerous Nor'easters and sustaining the full impact of Hurricane Isabel.
- Sand accumulation of the site has been impressive with 117,410 square feet of new beach created. Some 4,978 cubic yards of sand stabilizing a previously highly eroding beach where only water existed prior to the placement of the Beach Prisms. The mean high watermark has migrated westward over 40 feet and 7,465 tons of sand has accreted landward of the Beach Prisms. The 7,465 tons of sand accumulated on Terrapin Nature Area is equivalent to 310 dump truck loads of sand.
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Download "The Summary & Findings of
Using Beach Prisms For Shoreline Erosion
Control & Beach Replenishment" Report |
- The shoreline erosion existing in 1989 has been halted. The beach has extended over 40 feet westward and the tidal pond is no longer in danger from severe erosion or breaching its banks to the Chesapeake Bay.
These results of the Beach Prisms installation at Terrapin Nature Area proves conclusively that Beach Prisms work effectively against shoreline erosion and can accrete and capture significant amounts of sand to restore beaches. We believe that Beach Prisms are an extremely cost effective, economically viable and environmentally friendly method for shoreline protection. The slot design of the Beach Prisms allows the natural flow of water through the Beach Prisms which in addition to the parabolic curve of the Beach Prisms face dissipates the energy of the waves that crack against the Beach Prisms. Beach Prisms become artificial reefs in the water and provide sanctuary for marine life and help rebuild beaches through sand accretion and accumulation.
Sincerely yours,
Thomas D. Lane, PLS
President
Lane Engineering, LLC
View the Beach Prisms Study Report |
