Solar Distillation for Potable Water in Coastal Areas and Groundwater Quality Augmentation through Rainwater Harvesting Supported by World Bank India Country Level Development Marketplace 2004.
"Water, water everywhere, but not a drop of water to drink" – the background for this activity is to emerge sustainable process towards addressing water issues prevailing in the coastal areas.
Objective: To provide pure drinking water for households located in the coastal region through solar distillation, and simultaneously augment the ground water quality through rain water harvesting thus enabling groundwater exchange by utilizing traditional water bodies specific to the selected environment through local community participation.
Rationale: Fresh water availability in the coastal belts is rapidly declining and the shallow fresh water aquifers are replaced by saline and brackish water. There are incremental cases reported in water borne diseases, increased drudgery for women in fetching potable water from long distance. Many fresh water open wells and traditional ponds are gradually turning saline and discarded questioning sustainability of water supply interventions.
Solar distillation process utilizes any poor quality water available in the area, which is evaporated and condensed, thus making it safe and cater to household demand for drinking and cooking purpose (@3-4 lpcd). The water distilled leaves behind all the harmful salts, bacteria and other matters, giving out 100% safe potable water. The proposed system is to be assembled out of easily available materials and local human skills. The unit which can be installed at household or community level (3-10 households cluster) needs very low investment cost, zero operation costs and replicable. During rainy season, it can be altered for rainwater collection too.
Rainwater harvesting for groundwater exchange is for the qualitative improvement of shallow aquifer in the selected regions. Runoff rainwater from household premises is to be channelised into water bodies (existing unused wells and ponds) after minor filtration process. This process is to enable speedier entry of rainwater into the shallow aquifer, and thus displace/dilute salt water. Percolation of rainwater in sufficient quantities (especially post monsoon showers) would result in arresting the saline water intrusion.