Water Resources Research Act Program

Principal Investigators: Sangchul Hwang

Abstract: Despite the fact that desalination supplies about 80% of the water used in the United States Virgin Islands (USVI), greater than 50% of the residences in the USVI still use rainwater cistern. Annual rainfall averages 40 inches in USVI and is very seasonal so that desalinated water is often transported and refills the cisterns. From that point, there is a potential for improved water supplies to get exposed to secondary contamination from pumps, pipes and the trucks. Additionally, there might be contamination of rainwater before collected to the cisterns due to urban pollution, bird and reptile waste materials and particulate matter deposited. Also, if the cisterns have not been maintained well, there is another potential of contamination in the stored cistern water. Another case of cistern water contamination can be due to aged cistern structure, thereby infiltration of contaminants from the surrounding contaminated soil and ground water to the cisterns. Therefore, this research aims to develop and evaluate point-of-entry (POE), cistern water purification units (CPU) to ensure health and safety of people who rely on cistern water. To meet this end, low-cost, simple, POE sand filtration and disinfection unit will be first developed and tested in a lab-scale and then a scaled-up POE CPU will be evaluated at field. A long-term goal of this research is two folds: 1) to develop POE CPU benefitting many communities which rely on rainwater as their drinking water source (e.g., USVI), and 2) to contribute to capacity building for USVI through implementations and technology transfers of POE CPU.