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Researchers Test Beach-Nourishment Protocol 10 The Crest Researchers Test Beach-Nourishment Protocol An interdisciplinary team of VIMS isms and fish, and the possible researchers is wrapping up a multi- physical impacts to the off- year study in Virginia Beach designed shore dredge zone, the surf to help government agencies more zone, and the nourished beach. effectively monitor the environmental Study results included com- impacts of beach nourishment. puter models that MMS and Beach nourishment involves mining ACOE use to evaluate and sand from offshore or land-based implement beach-nourishment deposits and transporting it to beach projects. areas to make them wider and more The VIMS‘ studies were stable. instrumental in guiding MMS Geologists Woody Hobbs, Scott officials during their review of Hardaway, and Jesse McNinch have Virginia Beach‘s (successful) joined forces in the project with request for permits to exploit biologist Bob Diaz and computer the sand resources off its modeler Jerome Maa. Their goal is to shoreline. In fact, the MMS test the Mineral Management Service‘s was so satisfied with VIMS‘ (MMS) protocol for monitoring the efforts that the agency encour- effects of sand mining on the living and aged other institutes to use the physical resources of U.S. shorelines. studies as a template when The MMS is the federal agency submitting proposals for charged with issuing permits for sand- shoreline-impact studies in mining from federally managed off- other states along the Atlantic shore areas. seaboard. Sandbridge, Virginia (just south of Virginia Beach) before (L) and after (R) beach nourishment. Beach nourishment is a some- —Ultimately, though,“ says The beach is much wider in the after-nourishment photo, even though that photo was taken after times-controversial practice with costs Hobbs, —MMS realized that Hurricane Isabel. and benefits to both the economy and their studies were about the the environment. The Army Corps of potential impacts, and that follow- last longer and have fewer detrimental beach erosion. Hardaway is investigat- Engineers (ACOE) spends about $80 through to see what really happened environmental effects.“ ing the best ways to monitor a nour- million a year to maintain the nation‘s would be of great benefit. So they set The current VIMS study is de- ished beach to ensure that it lasts as coastline against erosion and rising sea about to create a protocol for monitor- signed to review and enhance a trial long as possible. Diaz is exploring how level, with local governments chipping ing offshore sand-mining areas.“ protocol that was developed by a best to conduct long-term studies of in another $40 million. In addition to —Monitoring would allow us to consultant using information obtained impacts to bottom-dwelling organisms supporting a healthy tourism economy assess the accuracy of the predictions during a December 2000 meeting of in the dredge zone. Maa is testing a that generates billions of dollars that were used in the design and scientists, engineers, and resource low-cost radar system for monitoring annually, healthy beaches can play a consideration of the dredging process,“ managers at VIMS. wave height shoreward of the dredge major role in protecting the shore from notes Hobbs. —That would help im- The VIMS study is multifaceted. area (see sidebar). storms and erosion. Critics contend prove the predictive models so that McNinch is studying how subsurface The team expects to deliver its that some beach-nourishment projects subsequent nourishment projects will geology in the surf zone helps controls final report to the MMS in early 2006. actually hasten coastal erosion, and that the practice is ultimately unsustain- Maa Rises to the Occasion able. The Mineral Management Conference Center in Virginia Beach. potentially saving the agency about Virginia Beach, the Common- Service‘s initial protocol for monitor- —They were very kind to provide this $50,000 dollars at each radar-moni- wealth‘s most popular seaside destina- ing beach-nourishment projects called high ground,“ says Maa. —You need a tored sand-mining site. tion, has spent about $110 million on its for use of a buoy to monitor waves at certain height to use radar for better Preliminary results suggest that 30-year beach-stabilization project, and project sites, but VIMS researcher wave images. The ideal height is 30 the radar holds promise for long-term earns about $40 million in taxes from Jerome Maa and others were con- meters or more.“ monitoring of beach-nourishment the $500 million in tourist revenue that cerned that a single buoy would not Unlike traditional wave gauges, efforts. —Radar is not a perfect the beach generates each year. provide broad enough spatial cover- which measure actual vertical displace- technique, but it is reasonable,“ says The current study builds on VIMS‘ age for meaningful results. Maa is ment, radar images provide only a Maa. Land-based radar units are long history of collaboration with MMS, thus testing the effectiveness of using relative measure of wave height. cheaper to maintain and operate than ACOE, and other coastal-management a low-cost radar system to monitor Maa‘s most recent research effort was traditional marine gauges, and provide agencies. —We‘ve had a series of one- wave height along the beach. The thus to place a pressure gauge within much wider coverage. to-two year projects going back over a current radar unit provides coverage the radar‘s field of view in order to Due to budget cuts, the Army dozen years with MMS, looking at over a radius of about 2.5 kilometers. calibrate or —ground truth“ the radar Corps of Engineers no longer oper- various aspects of beach nourishment —The long-term goal is to use data. The gauge was deployed this past ates a wave gauge for Virginia in Virginia Beach,“ says project leader easily available X-band radar to spring by marine technicians Bob Beach. —But there is a need to know Hobbs. monitor the wave height and current Gammisch, Tim Gass, and Wayne wave conditions and to use that as The initial studies defined the field,“ says Maa, —That‘s important Reisner, and graduate student Ho input to better simulate shoreline available reserves of sand offshore of because wave conditions affect Kyung Ha. response,“ says Maa, —so I think that Virginia Beach. A more recent study sediment transport, the beach profile, Maa has also been working to with local support, we will go back. focused on the potential environmental and erosion along the beach.“ develop the software needed to Everyone is interested in maintaining impacts of offshore mining. VIMS Maa stationed his radar unit atop interpret and analyze the radar images, a stable beach.“ scientists assessed the possible biologi- the 12-story Clarion Resort and cal impacts to bottom-dwelling organ-.
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