Monitoring urban storm water: facing climate changes in a Mediterranean coastal city

Abstract

In the actual global climate change scenario, Mediterranean cities are particularly vulnerable to floods and droughts, destabilizing the urban water cycle. During the intense precipitation events, more than in normal rainfall scenarios, the resulting diffuse pollution can be a major threat to the natural ecosystems and human health. Therefore, the characterization of the urban storm water runoff is considered of the utmost importance to the region, and was the main objective of this work. With this purpose, a monitoring plan for urban storm water of Faro (Portugal) was developed. Representative sampling locations, frequency of sampling and analytical parameters were defined. A major storm of the 2014–2015 wet season was monitored. The analytical parameters were TSS, BOD, COD, pH, Conductivity, TN, TP, Ni, Cd, Pb, Total Hydrocarbons and E. coli. Results showed that, mainly during the first 45 min of the precipitation event, some levels of pollutants (e.g. Pb), can be high enough to cause serial disturbances in the Ria Formosa ecosystem and thus in human health.