Assessment of marine water quality and its suitability for recreational activities in Pasikudah beach

Abstract

Coastal waters are used for a variety of leisure and recreational activities. Water pollution can significantly reduce the demand for recreation. Assessment of recreational water quality is a useful tool in pollution control and developing mitigation measures. The present study was undertaken with the view of assessing marine water quality of Pasikudah beach to evaluate suitability for recreational activities, identify pollution sources and possible mitigation ways to solve pollution issues. The research was carried out monthly for 06 months period from June to December 2017. Marine water quality results revealed that average pH (8.03), Turbidity (9.94NTU) and temperature (30.2 0C) values were within the recommended threshold limits. Electrical Conductivity (EC) and salinity ranges were 46.46- 58.16mS/cm and 27.63- 33.52PSU respectively. Electrical conductivity and salinity had a positive correlation, and It was noted that salinity and EC values were lower on November and December than other months due to rainfall which causes dilution of salts. Also, Measured Dissolved oxygen values (6.23-8.21mg/l) were above the minimum required level (4mg/l). This study suggests that the experimental sites were not experiencing any oxygen deficiency at that time. Recorded nitrate and phosphate value ranges were 0- 2.8mg/l and 0.13- 4.51mg/l with the mean value of 0.63 and 1.36mg/l respectively and these values exceeded the standard values for the recreational site. Substances such as fertilisers and detergents carried by Pasikudah canal, sewage and stormwater runoff during the rainy season may be reasons which increase nutrients level in seawater. Total Coliform and Escherichia coli counts were ranges between 0-93 and 0- 40MPN/100ml with the mean value of 16 and 6MPN/100ml respectively and measured values were within threshold limits. So, based on overall results; Pasikudah beach is suitable for recreational activities.