Bantayan Island water resources study

The increasing pressure for development in Bantayan Island led into the study of the water resources status. Two parameters were considered vital in the study, these are the quantity of useful groundwater reserve and the water quality. Well surveys were conducted in two separate occasions to determine the groundwater level. The first survey was done in 1988-1989, and the second survey was conducted in 1995. In the second survey, assessment of the groundwater quality was also undertaken. Results of the study showed that despite sufficient annual potential recharge in the island there is still an observable decrease in-the groundwater table. Salinity concentration increases on water sources near the coasts which indicates movement of saline wedge towards the inland. Wells near the coasts have recorded chloride concentration of 250 ppm and above. This value exceeded the maximum limit set by the World Health Standard for drinking water. It was recommended that monitoring of groundwater level and quality of water be conducted. A design of water recovery system will be made to optimise the withdrawal of water without any detrimental impact to the groundwater reserve.