Oceanographic Parameter Characterization For Punta Bandera, Baja California, Based on a Short-Term Sampling Period and Nearby Data
Fernando G. Marván and Luis F. Navarro Olache
An oceanographic study of waves, currents and water quality measurements is presented to analyze the potential effect of health related issues to bathers. The study site is located on the Pacific coast of Mexico approximately 20 Km south from the border with USA. A set of data were taken from July to September 2007 and from December 2007 to February 2008 which represent summer and winter conditions. Water quality and surface current data from the San Diego Coastal Ocean Observing System (SDCOOS) and the Coastal Data Information Program (CDIP) were compared to the sampled data and relationships were established. In general it was found that the relationship between both water quality datasets is weak except for the rainy season. Wave data from three CDIP stations showed good agreement with the site data. The currents distribution revealed that the alongshore flow is characterized by stronger southward currents 75% of the time and weaker northward currents about 25% of the time. The main flow regime is around 0.2 m/s, with some exceptions as shown on February 22, 2008, when values of up to 0.4 m/s were observed. Water temperature oscillated between 10 and 15 degrees Celsius. Water quality shows the highest levels of coliform bacteria occurred during winter, associated with the rainy season and runoff. Urban contamination bacteria levels, during the summer months were below the thresholds established by international regulation, for fecal coliforms and enterococci. The levels during winter were higher than the established thresholds on two occasions for total coliforms and on one occasion for fecal coliforms which correspond to 16% and 8% respectively from the total number of samples taken. In general, the study site samples show a similar behavior than those near the USA water treatment plant discharge.
Keywords: Water quality, coastal currents, ocean waves, coastal pollution, Mexico-USA border