Coastal flood assessment due to extreme events at Ensenada, Baja California, Mexico.

Abstract This paper examines the risk of coastal flooding in Ensenada and surroundings. Using topo-bathymetric surveys, wave and wind data, tidal time series and numerical modelling, a set of flooding maps were obtained to show the effects of sea level variability related to extreme events for different return periods. Results show that flooding in the north of the study area is low, since cliffs of up to 6 m height dominate the geomorphology, so no considerable threat to human assets is envisaged. The south of the area is different; flooding levels could reach human settlements and affect the Punta Banda Lagoon. The flood levels that affect the study area are those associated to return periods of 50 years, while those of return periods 2, 5, 10 and 25 years do not suggest considerable flooding. Thus, as long as there are no substantial modifications of anthropic origin in the coastal zone of Ensenada, the risk of flooding due to extreme events is low, although it is important to consider the erosion that these phenomena could be cause. Highlights • For the first time full flooding maps have been developed for Todos Santos Bay, Mexico. • Topobathymetric and hidrometeorological data and numerical modelling were used to estimate flooding maps for return periods. • Flood levels significantly affecting the study area are those related to 50 years return period. • Risk of flooding due to extreme hydro-meteorological phenomena is low at the north, and moderate at the south of the Bay. • Is important to consider that even low flooding can produce beach erosion. [ABSTRACT FROM AUTHOR]