Evaluating a Large-Scale Batch Chlorination Method for Household Cistern Water Treatment in the US Virgin Islands

• Published in: Journal of environmental engineering (New York, N.Y.) N.Y.), 2022-10, Vol.148 (10)
• Main Authors: Voth-Gaeddert, Lee E., Lemley, Mandy, Willford, Ignacio, Brathwaite, Kela, Momberg, Douglas, Schranck, Andrew, Libbey, Stephen
• Format: Article
• Language: English
• Subjects: Chlorination; Chlorine; Cisterns; Contamination; Costs; Decay; Decay rate; Domestic water; Dosage; Evaluation; Households; Islands; Microbial contamination; Microorganisms; Rain water; Rainwater recovery systems; Roofs; Technical Papers; Variability; Water harvesting; Water pollution; Water quality; Water treatment
• ISSN: 0733-9372; 1943-7870
• DOI: 10.1061/(ASCE)EE.1943-7870.0002059

AbstractIn the US Virgin Islands (USVI), roof-harvested rainwater is a primary source of domestic water and is collected in large cisterns and pumped throughout the household premise plumbing system. However, previous literature suggests that roof-harvest rainwater is prone to microbial contamination. A common local water treatment practice is direct batch chlorination of this water (>20,000 L). Provided this local habit, Love City Strong (LCS) established a pilot program to evaluate if direct batch chlorination of water in cisterns was effective and economically feasible to produce consistently adequate levels of free chlorine residual (FCR) at the kitchen tap. A trained field team utilized nine actively used cisterns to conduct a series of chlorine dosing trials where the cistern water was dosed, and, subsequently, monitored every three days. Water quality data were collected throughout, and new trials were initiated once FCR values reached ≤0.05  ppm. Evaluation criteria included: (1) the variability in duration between a dosing event and an FCR measurement