Sea level variations in El-Burullus new harbour, Egypt

Abstract

El-Burullus new harbour is one of the newly established harbours in the Nile Delta region along the Egyptian Mediterranean coast. It has been mainly developed to serve the fishermen community in El-Burullus region. The Harbour lies within the territory of Lake Burullus in the Nile Delta, which is one of the well-known low-elevated coastal zones in the Mediterranean basin. The present work provides a comprehensive sea level analysis including different terms and useful information, which can be used for the mitigation plans and protection measures in the vicinity of the Harbour, and contribute in our understanding of the nature of the sea level variations in front of the Nile Delta. The study is based on hourly data of sea level over 6 years from January 2003 to December 2008. The results revealed that tides in El-Burullus new harbour region are of semidiurnal type, the sea level variations are of seasonal behaviour, and the mean annual level is of increasing trend. The impact of the meteorological factors on the observed sea level in the Harbour is almost twice that of the astronomical factors. No extreme sea level year appeared at El-Burullus new harbour during the study period. The return periods and the design lifetime risk were calculated; in order to reasonably mitigate and secure coastal structures in the territory of the Harbour. Over the study period, the highest probabilities of occurrence were concentrated in the levels between 0.40 and 0.85 m, while the lowest were above the level of 0.90 m. While the return periods for the 0.45 m and 0.50 m were ~ 64 and 20 years, respectively, they were 11, 29 and ~ 78 years for the 0.80 m, 0.85 m and 0.90 m levels, respectively.