A study by IIT Kharagpur researchers has connected the dots between the impact of economic growth reducing fecal coliform (FC) pathogens in groundwater which is a key factor causing water-borne diseases in the densely populated Indo-Ganges-Brahmaputra river basin.
About 100,000 children in India are dying every year from waterborne enteric diseases like diarrhea. While the study reported the excess of fecal coliform concentration in potable groundwater in rural regions in the said area, it also made first-time observations on a significant reduction of fecal pathogen concentration in the spatially variable groundwater from 2002 to 2017.
“Looking beyond the country globally, more than 2 billion people, mostly living in economically stressed areas of Africa and South Asia still do not have access to basic sanitation, and more than 1 billion still opt for open defecation. The resulting unsafe disposal of faecal waste to nearby drinking water sources poses an extremely serious environmental crisis and public health concern,” says Prof. Abhijit Mukherjee, faculty at the School of Environmental Science and Engineering and Dept. of Geology and Geophysics at IIT Kharagpur who led the research project.
The researchers studied data for the densely populated Indo-Ganges-Brahmaputra river basin, across 234 districts in Rajasthan, Haryana, Uttar Pradesh, Bihar, Jharkhand, Chhattisgarh, West Bengal, Assam and also Delhi and NCR and a population of ~ 400 million. The study data collected from National Rural Drinking Water Programme, Ministry of Drinking Water and Sanitation, Govt. of India, covered almost last three decades to delineate the long-term improvement trends of groundwater quality across India, as a consequence of the development.
Uniqueness in this study to determine economic development trends and correlations was the use of nigh-time light data instead of GDP or other economic growth data. “We have used satellite-based Night-time Light information based on Defence Meteorological Satellite Program of the US Air Force, archived by NOAA/NASA for the period 1992-2013. In most areas economic development, suggested by increasing satellite-based nightlight correlated to the reduction in fecal coliform concentration and alleviation of water quality,” explained Srimanti Duttagupta, a Ph.D. scholar at IIT Kharagpur, first author of the research paper which has come out recently based on this study.
The other dataset used was high-resolution geographically spatial information of waterborne fecal pathogen concentration in groundwater from the period 2002-2017. Numerical and statistical analyses were performed on aforesaid culled datasets to understand the efficiency of development in alleviating the water quality and public health, and relationship with economic development. The study showed that the spatially variable groundwater faecal pathogen concentration from 2002-2017 has significantly decreased across the basin. From 2002 – 2013, Night-time Light on the surface area as seen from satellites increased by +3.05% per year and faecal coliform pollution decreased -1.39% per year.
The research group observed a significant decrease in groundwater fecal coliform concentration after 2014, in the acquired data. This could be a direct outcome of improved sanitation construction and utilization of sanitation structures, instituted by the Clean India (Swatch Bharat) mission of the Government of India Prof. Mukherjee remarked, however, needs more data to confirm. “Nevertheless, in areas with inferior water quality, improper human practices outweigh economic development in affecting human health,” he added.
It was observed that areas with lower literacy rate and very high population density suffer from poor groundwater quality because of faecal coliform pollution, irrespective of economic development. The problem of overpopulation and slums is an intricate problem which is reflected in all life aspects in countries like India. The study reflects through results that higher faecal coliform concentration in urban, and peri-urban areas, suggesting economic progress may not be the only influencing factor on water quality alleviation.
The researchers opined that social behavior and practices, use and disuse and beliefs are mostly related to lower literacy rate. In turn, these results lack awareness and encourage malpractice on sanitation, eventually leading to increased fecal waste into drinking water sourced to groundwater.
The research was published this year in the Journal of Earth System Science published by Indian Academy of Sciences.