Dr. Paul Pavelic1, Mr. Mohammad Faiz Alam1, Dr. Alok Sikka1, V.K. Mishra2, Dr. C.L. Verma2, S.K. Jha2, Dr. Reddy V. Ratna3, Dr. Mini Govindan4
1. International Water Management Institute (IWMI)
2 .Central Soil Salinity Research Institute (CSSRI)
3. Livelihoods and Natural Resource Management Institute (LNRMI)
4. The Energy and Resources Institute (TERI)
Technological innovations are needed to help rural communities in developing countries better deal with floods and droughts, particularly given that climate change is exacerbating the impacts of extreme water variability on agrarian communities. Managed aquifer recharge (MAR) can help overcome the spatio-temporal mismatch in water availability through targeted recharge of excess seasonal flows into depleted aquifers, thus reducing local/downstream flooding and drought risks by boosting groundwater reserves. This presentation would give an overview of the novel yet pragmatic MAR approach developed and details the outcomes and learnings derived from its implementation on the Upper Gangetic Plain in India. In the Indian context, MAR has traditionally been applied in arid and semi-arid areas and not in flood-prone areas where groundwater levels have more recently started declining.
The proof of concept for MAR involves a multi-disciplinary approach combined with incremental staging from concept to scaling-up to ensure that major risks are identified early and addressed. Specific activities include suitability assessments, community mobilization and capacity building, pilot testing and demonstration, hydro-economic modelling, and institutional analysis.
With regional mapping showing that much of the Upper Gangetic Plain is potentially well-suited to MAR, a pilot site was established in western Uttar Pradesh and operated for several years. Monsoonal flows recharge the shallow aquifer via infiltration wells drilled into the base of a formerly abandoned community pond. Results showed that significant quantities of water (30-60 ML) could be stored underground each year without unduly compromising groundwater quality.
Acceptance of MAR by the local community was made challenging due to the dampened groundwater level response to recharge in the alluvial aquifer targeted. Accordingly, the institutional arrangements put in place had to be fine-tuned over time. Integrated hydro-economic modelling suggests that scaling-up MAR across the 17,000 km2 Ramganga basin would generate significant social and economic benefits by reducing floods, restoring groundwater levels and dry season baseflows, and boosting agricultural production. Calculated returns on investment through flood mitigation and enhanced agricultural production appear favorable.
Prospective potential entry points for inclusion of MAR in policies and programs associated with groundwater, irrigation, flood, rural development, disaster management, CSR and others are being analyzed. The MAR approach has been included in district level development plans and efforts are underway to implement next-level scaling-up. Although current experience is firmly grounded in the Gangetic Plain, there are clear opportunities to apply this form of MAR in other regions globally.