Developing statistical downscaling to improve water quality understanding and management in the Ramganga sub-basin

Published: 18 May 2021

This project will deliver world leading statistical research supporting the development of a water quality monitoring and modelling framework for the Ramganga sub-basin of the Ganges river basin.

Empowering social inclusion through 'improving access to clean water and sanitation' for all requires a
robust understanding of water-related ecosystems and the benefits that they can provide to society.
However, 'the global data currently collected through the SDG process do not reflect the general state or trends known about freshwater ecosystems'. Novel mathematical sciences research is essential to enable fusion of Earth observation and on-the-ground data sources to fill the knowledge gaps, provide improved understanding of water quality and address the water management challenges faced by developing countries. This proposal will deliver world leading statistical research supporting the development of a water quality monitoring and modelling framework for the Ramganga sub-basin of the Ganges river basin.

Traditional water sampling is based on a small number of sites, and is very labour intensive and expensive, and our proposal brings together data from new in-situ sensors, delivering data at high temporal frequency, coupled with intensive coupling high-end in-situ above and below water characterisation of the biogeo-optical properties of the Ramganga with measurements from calibrated miniaturised hyperspectral imaging radiometers deployed from drones, and data from new satellite missions (Sentinel 2). Together, these provide an efficient and unprecedented means of collecting significant data across a range of environments and pollution discharge scenarios of optical water types in the Ramganga basin. Coupling these data with conventional measures of WQ will provide the much desired framework for extrapolating WQ data at hitherto unachievable spatial and temporal resolutions.

Covering 26% of India's total landmass, water quality and water resources in the Ganges basin are vital
for the wellbeing of one of the largest and densest global populations (43% of India's population).
However, they are being compromised due to activities such as rapid industrialization and
urbanization, and mitigation efforts are hampered by lack of historical and contemporary discharge and quality data. This project will develop and implement new statistical methodology specifically for the Ramganga sub-basin to integrate the new and existing water quality data with remote sensing satellite data (both historical data from multiple sensors and new retrievals from recent Sentinel missions).

To address the water quality challenges in the Ramganga sub-basin and to fully utilise the new data streams, novel statistical downscaling and data fusion methodologies through a varying coefficient, hierarchical Bayesian modelling framework will be developed to incorporate river network structure and model quantiles of flow. These approaches support integration of disparate data sources to enable prediction of water resource condition and associated uncertainties to inform risk-based modelling under a range of socio-economic and climate change scenarios, and provide tools to inform future monitoring design. The output of catchment-wide WQ estimates will be made available to policy makers and future researchers to guide policy and design future sampling sites and temporal frequency.

Planned Impact

The key beneficiaries and direct users of programme outputs are: (1) the research community; (2) government ministries and departments; (3) implementing agencies, such as local government and NGOs; (4) urban and rural communities within the Ganga river basin who will be the ultimate beneficiaries.

Research community: The project will deliver a step-change in data availability and fill a key gap in research capacity in the Ganga river basin bringing together world-leading Earth observation datasets, with previously un-connected in-situ research and data in their social and economic context. This will deliver new, powerful and transformational inter-disciplinary knowledge, relating to freshwater quality, and institutional operations surrounding our freshwater resources. New understandings developed will be disseminated through high impact journals and international fora. Open access to the datasets, to ensure future comparative and longitudinal interdisciplinary research, will be ensured.

Policy community: This project's strategic importance from a UK perspective arises from the 'reach' and 'significance' of the project which if properly realised can make a globally significant contribution to the quality of life and ultimately the economic prosperity of millions of city and rural in the Ramganga river catchment. Impact will come from the contribution our work will make to the National Mission for Clean Ganga (NMCG) which agreed the requirement for Urban River Management Plans (URMPs) for all Class I and II 'towns', effectively all urban centres with over 50,000 inhabitants, in the Ganga River Basin. Our research and findings concerning river water quality and its dynamics will allow improved management at a national level.

Basin Authorities and national institutes: A major outcome from this research is to understand better sources, pathways and fate of water pollution in the context of rapidly growing and frequently unplanned urban centres in India. We will engage with multiple national, regional and local basin authorities including CCanga and at the local level through Central and State Pollution Control Boards etc. The new high-quality data sets will be used to develop an informed strategy for future long-term monitoring and the development of a decision support tool to formulate an informed, economical and effective plan.

NGOs: we will work with several international and local NGOs such as WWF-India, Aquawatch and Mahasheer foundation to help local communities to understand the impact of water quality on their livelihood, agricultural products and human health. We will also aim to spread the findings of this project into the local communities to increase their awareness and to support the Clean Ganga drive of the Government of India.

Urban and rural inhabitants: The livelihoods and wellbeing of local communities are directly impacted by clean water. We will undertake targeted stakeholder engagement and detailed mapping of pollution sources and transmission pathways in several locations. Whilst we will create a powerful new high-quality evidence base of water quality, we are fully cognizant that it is only through endeavours in public education, capacity building, socio-economic policy adjustments and legislation in other fields of environmental protection that successful local management of the urban centres can be achieved. We anticipate that the new statistical approaches developed in this project will contribute to improved environmental outcomes and lead to significant health benefits, particularly to more vulnerable communities.

First published: 18 May 2021