An Investigation of Littoral Transport Between Virginia Beach and Sandbridge, Virginia

A method for calculating littoral transport, direct determination of the sediment flux, has been proposed and evaluated. Three sampling stations, located between Virginia Beach and Sandbridge, Virginia, were occupied for a period of thirteen months (September, 1972 to September, 1973). Measurements include velocity of the littoral current, cross-sectional area of the surf zone, and in situ samples of suspended and bottom sediment load. Observations of sea and atmospheric conditions were obtained. Two ways of calculating littoral transport were derived from the same basic method, thus two sets of transport values were generated. Two annual littoral transport values were calculated by use of these figures and regional wave data. The numbers were 1.2 x 1012 and 9.6 x 1011 grams per year or 355,000 and 294,000 cubic yards per year. Tidal effects on the rate of littoral transport were examined. Transport was greatly affected by changes in cross-sectional area and subsequently in the shape of the zone of littoral transport due to the tidal fluctuations. In addition, beach cusps in conjunction with tidal rise and fall were found to affect the littoral current; cusps were found to retard littoral current at high tide, but were ineffectual at low tide. It is felt that more work needs to be done in both evaluation of the method and investigation of problems that were encountered.