Rapid assessment of coastal water quality for recreational purposes: Methodological proposal

Coastal waters and beaches are the main tourist attraction in the Caribbean, reporting an estimated income of US $ 25 billion dollars a year. However, sewage discharge, solid waste leachates, and oil spills threaten these resources, requiring management strategies to control water quality, which sometimes is difficult given the lack of adequate technical tools. The present article proposes a quick methodology to determine the quality of coastal waters for recreational purposes, using San Andrés Island, Colombian Caribbean, as a study case. The proposal includes seven variables indicative of water quality, in three scenarios: normative, permissive and restrictive. The methodology initially uses a univariate weighting that qualifies the water quality at each sampling station by parameter, then a multivariate weighting to determine the quality with the set of indicator variables and its comparison with a general pollution scale. The application is presented with a dataset of 15 sampling stations between 2001 and 2016 from the systematic coastal monitoring network implemented by CORALINA. The results lead us to conclude that the proposed methodology is a useful tool for a rapid assessment of coastal water quality in areas destined to recreation by primary and secondary contact. It is also an input for the elaboration of management plans in coastal zones.