Environmental impact of beach nourishment: A case study of the Rio San Pedro Beach (SW Spain).

Resumen

The beaches on the left bank of Rio San Pedro (SW Spain) are in a regressive state because of the human activities of recent decades. With the objective of minimizing the effects of the erosion, the Spanish Coastal Department (Ministry of the Environment) decided that the most suitable solution was to provide sand nourishment. Previously, an environmental impact study (EIS) was carried out on these beaches, and an environmental monitoring campaign was also completed during that nourishment. A new methodology to perform this kind of studies is proposed in the present report. Moreover, a form is proposed for establishing the degree of observance of the EIS. Additionally, discrepancies in opinions on the alleged environmental impact of the sand nourishment on the Uca tangeri (European Fiddler crab), a representative but not protected species that lives in the area of research, led to the development of a complementary study. Therefore, observations, experimentations and calculations were carried out on individuals of this species of crab. It was concluded that there was no significant impact on this crab’s population. With respect to the impact of the sand nourishment project, the overall impact was negative but negligible during the nourishment phase. Once the project was finished, the total environmental impact was also negligible but positive overall.