Sustainable application of edible solute to control reservoir evaporation loss

Recently, water preservation globally, particularly in Indian cities, has been prominently featured in newspaper headlines, underscoring its importance. This research explores the innovative use of edible solutes to tackle the challenges of evaporation in reservoirs, including water loss, increased salinity, and ecological disruptions. Traditional methods for controlling evaporation often have environmental drawbacks and high operational costs. By evaluating the environmental impact, cost-effectiveness, and feasibility of edible solutes such as mustard oil, neem oil, til oil, castor oil, cetyl alcohol, and stearyl alcohol, this study investigated their sustainable application in eight reservoirs across Andhra Pradesh and Telangana states in India. Through break-even analysis, the economic viability of edible solutes is compared to that of conventional methods over the lifespan of a reservoir. These findings suggest that edible solutes offer a promising and environmentally friendly alternative, reducing evaporation rates while minimizing the adverse effects on water quality and ecosystems. Despite the initial investment costs, the long-term savings and environmental benefits surpass those of the conventional approaches. This study estimated evaporation rates for eight reservoirs across Andhra Pradesh and Telangana in India (3049 mcm of water/year), showing a significant reduction when cetyl alcohol was used as a solute. Cetyl and stearyl alcohols are highlighted as practical and cost-effective evaporation retardants. Considering the cost of water at one paise per five litres of saved water, the break-even point (BEP) analysis for the adopted scenarios reveals that BEP is achieved for 30%, 10%, and 5% reduction in evaporation within one, two, and three months, respectively. Similarly, for scenario II (one paisa per one litre of saved water), the BEP was achieved at the beginning, 1.5 months, and 2.5 months, considering evaporation reduction by 30%, 10%, and 5%, respectively. Future research should validate the efficacy of microfilms in mitigating evaporation using time-resolved interferometry techniques. This study advocates sustainable water management practices and provides valuable insights for policymakers, water resource managers, and stakeholders seeking efficient solutions for evaporation control in reservoirs.