Quantification of sediment loss from semi-sheltered beaches: a case study of Valgerand Beach, Pärnu Bay, the Baltic Sea

K. Kartau¹, T. Soomere¹ and H. Tõnisson².

¹ Institute of Cybernetics at Tallinn University of Technology

² Institute of Ecology at Tallinn University

A systematic estimate of the sediment budget is presented for the northern coast of Pärnu Bay, the Baltic Sea, where the littoral drift of sand from Valgerand, an eroding sandy beach, is directed to the east and finally blocked by the jetties in the Pärnu River mouth. The estimate is based on an application of the theory of the equilibrium beach profile and a comparison of a map produced at the turn of the 19th and 20th century with contemporary maps. The eroding section is relatively short, about 1 km in length, and loses about 1000 m³ of sand annually. Most of the northern coast of Pärnu Bay shows features of longshore sand transport. The major accumulation area is located to the north of the Pärnu River mouth where up to 4000 m³ of sediment accumulates annually.