Beach Erosion in San Benito Chiapas, Mexico: Assessment and Possible Solution

The study area is on the Gulf of Tehuantepec, where a harbour was built at San Benito, near Tapachula, Chiapas, in 1972. Two breakwaters, of 630 m and 800 m, respectively, were constructed to provide protection to the harbour channel. Erosion problems were detected near the harbour even before it was opened to trade. The original design had many flaws as no wave climate analysis had been done and littoral drift had not been taken into account. In 1975, 17 groins were built with the aim of reducing the erosion on the adjacent beach. These were unsuccessful and, in 1980, a rock armour apron was built at the most seriously eroded section in a further attempt to minimize the problem and to protect the population. However, the erosion continues at a rate of around 25 m per year in some sections. Commercial and navigation activities at the harbour are important for the population of San Benito and its surroundings, so coastal management policies must facilitate harmonic coexistence between human activities and the coastal system. This study analyses the problem and offers alternative solutions for minimizing the beach erosion using hard and/or soft solutions.