By Victor Tine
Staff writer
September 19, 2008 03:50 am PLUM ISLAND — Sand is migrating along Plum Island to the site that needs it the most, according to an independent study by a local resident. Michael Morris of Harvard Way spent five months earlier this year studying the flow of sand on Plum Island over the last 300 years, using aerial and satellite photos, maps, charts and scientific data from several sources. Among his conclusions was that two separate streams of sand are migrating toward Plum Island Center, which has sustained serious beach erosion in recent months. Erosion at the Center has been so severe that part of building deck had to be removed in May because the dune on which it stood had been washed away. Morris' study, called "Unlocking the Mystery to Beach Erosion at Plum Island," will be presented next Wednesday from 6 to 8 p.m. in the Newbury Elementary School auditorium. In his study, Morris said he has found that one stream of sand is moving south from the mouth of the Merrimack River along a submerged offshore sand bar, while another quantity of sand is flowing north from the Parker River National Wildlife Refuge's dune system. The southward flow, he said, is made up of sand that has accumulated since the Merrimack River channel was last dredged in 1999. "Due to a nine-year hiatus in dredging, there is now a healthy stream of sand migrating out from the river to the delta bar and back toward Plum Island," Morris said in a written statement. "Concurrently, a large ribbon of sand that was released during the April 2007 storm from the Parker River Wildlife Refuge barrier dune system is now flowing north toward Plum Island Center. "The two sand streams have not yet reached the center, which, as we know, has a deficit of sand; however, there does appear to be sand on the way," he wrote. Although not a professional scientist, Morris is a lifelong resident of the area who has spent many years on the water. He has studied physics, oceanography and meteorology. For the study, he consulted recent photos that were analyzed in light of historical documents. He also used state shoreline data, 15 years of recent satellite photos, Army Corps of Engineers dredging statistics and 7,000 hours of weather buoy data from the National Oceanic and Atmospheric Administration. He has reached the conclusion that the net migration of sand along Plum Island's shoreline is in a northerly direction, a departure from the conventional wisdom that it flows southward. Wednesday's presentation will be divided into two segments with a 15-minute break in between. Refreshments will be served.
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