Coupled Human And Natural Systems Environment (CHANSE) for water management under uncertainty in the Indo-Gangetic Plain

Managing water resources in the Indo-Gangetic Plain (IGP) is a tremendous challenge because of the basin's uniqueness in scale, biophysical complexity and the dynamics of its institutional and socio-economic characteristics. Agricultural intensification for food security, combined with unmanaged and inefficient water abstraction for irrigation, and poorly controlled waste management practices, has led to degradation of water resources both in terms of quantity and quality, endangering ecosystem services and human health. Extensive water use is directly linked to the energy sector, and contributes significantly to total carbon emissions. The hydrology of the basin is additionally affected by intensive urbanisation that reduces infiltration and recharge to groundwater. Ultimately, water management in the IGP is challenged by the imbalance between water demand and seasonal availability related to the monsoon cycle, and difficulties in coordinated planning of surface water and groundwater use strategies. Land use and land cover changes, which can modify evapotranspiration, may feed back to large-scale hydro-climatic processes and additionally, disturb the fragile human-natural system of the basin. Management of water resources in the IGP faces additional difficulties because of the local regulations and governance. Lack of cross-sectorial cooperation leads to competition for scarce water resources, while significant governmental subsidies for irrigation water and electricity potentially lead to significant wastage of resources. Finally, the basin's groundwater resources that are, to a large extent, a primary source for irrigation and rural and urban water supply, are independently managed by multiple agencies.

Considering expected population growth and impacts of climate change, it is clear that achieving water security in India and especially, the IGP, is a growing challenge that requires interdisciplinary collaboration across sectors, local communities, institutions and academia. This project brings together researchers from leading UK (Imperial College London, University of Exeter and British Geological Survey) and Indian (IISc Bangalore, IIT Bombay, IITM Pune, and ATREE Bangalore) institutions, in partnership with international (UNESCO) and local (CEEW) non-governmental organisations, to support water management in the IGP.

The overarching aim of the research is to improve mapping and quantification of dominant interactions and feedbacks between human activities and the hydro-meteorological system of the IGP. This project will provide information for improved decision-making on water allocation for agriculture, drinking water, ecosystems and other needs. The project builds on recent joint UK/India-funded research involving the partners, which has developed a series of highly relevant datasets, tools and models. Specifically, we will: (i) estimate surface and groundwater availability under current and future short-term weather predictions and anthropogenic activities within the IGP using a fully coupled, land surface-groundwater modelling setup; (ii) investigate the propagation, in space and time, of interactions of water uses and needs within the natural system by integrating novel consumer and ecological flow demand modules; (iii) provide regional predictions of decadal, seasonal and sub-seasonal monsoon rainfall and flood forecasting for the IGP, using the Weather Research and Forecasting model coupled with the Community Land Model version 4.0 to inform development of alternative water management strategies; (iv) translate the improved understanding of Human And Natural Systems into IGP's water management planning for water, food and ecological security. The project will use the River Gandak sub-basin, which has been impacted by these issues, as a case-study catchment for process-understanding. Water management strategies and feedbacks of water allocation to local climate will be analysed at the IGP basin level.

The overarching goal of the project is to develop new science to support improved decision-making on water allocation to secure food, water and ecosystem services. We will do this by investigating the interactions and feedbacks between people and their environment - how do people impact natural hydrological systems, and how do these impacts constrain their activity? The new scientific decade of the International Association of Hydrological Sciences focuses on the urgent need to develop the new science that considers this dynamic interface between environment and society. This project directly addresses this crucial scientific challenge but importantly will also have significant benefits for people, and the quality of their lives. Specifically the project will benefit the following non-academic users:

Local communities: Through public engagement we will improve: 1) public understanding of the major drivers of water scarcity, and 2) people's capability to assess their impacts on water resources. Providing this information is crucial to empower citizens to make water-related choices that improve their quality of life. Our main target audience are the farmers along the Gandak floodplain, which will benefit through improved agricultural planning ensuring food security. Information on predicted inflows and desirable ecological flow regimes in different seasons can inform irrigation practices, such as adaptive water release from dams and barrages managed by the Forest Department. Other local actors include conservationists (e.g. WWF, Earthwatch), fresh-water ecologists, and the fishing community.

The private sector: Two key end-user groups have been identified, who are involved in the process of water management in the Gandak and Ganga basins: (i) the public water utility and (ii) the agricultural sector. The information generated will be transferred to two water and agricultural management institutes: the Tata Institute of Social Science (TISS) and the Water and Land Management Institute (WALMI) at Bihar. TISS is involved in on-site water and agricultural management and the products generated from the project will be of direct use to them. WALMI, an autonomous body under the Water Resources Department of the Government of Bihar targets existing irrigation systems affected by water-related problems. In addition, our wider end-user group includes the relevant energy sector authorities (Council of Energy, Environment and Water). The CHANSE framework will provide stakeholders with information that will lead to improving their decision-making on conjunctive use of surface and ground water and water allocation.

Non-profit international and local organisations: UNESCO IHP and CEEW will gain a stronger foothold within the case study area and especially, an insight into the problems affecting the local community regarding water usage, as well as opportunities for relatively small interventions that may achieve large improvements in local outcomes.

Government departments: Governmental departments, both the Central and State governmental offices, have given water management in India under climate and demographic pressures a high priority. The CHANSE framework will provide policy-makers with improved integrated regional assessments of both water demand and availability enabling better planning for water security at governmental level. Targeted government departments who may be benefit from the proposed work are:
- Water Resources Department, Govt. of Bihar: Issues related to utilization of water resources, irrigation, and flood control.
- National Water Development Agency: Involved in augmentation of water availability in the existing Gandak Canal System.
- Public Health & Engineering Department, Govt. of Bihar: Provides improved portable water supply and sanitation facilities, towards improvement in public health.
- Department of Environment & Forest, Govt. of Bihar: Involved in conservation of aquatic wildlife in the Gandak.