Technical and economic impact of water reuse as an integrated water resource management measure in rural water supply systems

Water reuse becomes an alternative in the conventional water supply systems, especially in regions where nonpotable use of drinking water, as for garden and grass irrigation, is predominant. This study evaluates the footprint of reuse on small water supply systems in rural areas, where raw water quality does not meet the drinking water standards, and complicated treatment is needed. Individual facilities for the reuse of potential rainwater, light gray, gray, and domestic wastewater in the households could lead to a decrease in nonpotable tap water use up to 60% and a decrease in households' annual expenses for water supply up to 93 €/household. The installation of individual facilities for common reuse of rainwater and gray wastewater requires the highest investment costs, but the optioǹs operational costs are between 15 and 20% lower than all other options considered. The drinking water treatment plant capacity reduction due to measures’ implementation enables from 48 up to 58% saving in the total operational costs for drinking water supply in the settlement. The shortest payback period and best economic impact of reuse for small-scale water supply systems are observed if rainwater and gray wastewater are reused together.