Invited lectures are 30 minutes (including discussion), all other lectures are 20 minutes (including discussion).
Hydrogeochemical assessment of groundwater in industrial region of Sonbhadra, Uttar Pradesh, India
Arif Ahamad1,2 and N. Janardhana Raju1
1 School of Environmental Sciences, Jawaharlal Nehru University, New Delhi-110067, India 2 Daulat Ram College, University of Delhi, Maurice Nagar, New Delhi-110007, India
The present study assesses the physicochemical parameters and pollution load of the groundwater with reference to the heavy metals (i.e. As, Hg, Cd, Cr, Cu, Fe, Mn, Zn, Ni,Co, and Pb) in Obra, Renukoot and Anpara industrial clusters of Sonbhadra district, Uttar Pradesh, India. 220 groundwater samples were collected during post- and pre-monsoon seasons. Piper diagram showed that most of the samples are of Ca-Mg-HCO3-Cl-SO4 type. Gibbs plot depicted that weathering of rock minerals has affected the hydrogeochemistry of the study area. Fluoride contamination was observed only in few borewells of Renukoot and Anpara whereas nitrate contamination was observed in most of the borewells of all the three clusters in both the seasons, as per WHO standards. The primary cause of nitrate contamination in the groundwater was found to be from anthropogenic sources such as sewage and manure. Water quality index (WQI) value showed that groundwater in the Anpara cluster had worst quality followed by Renukoot and Obra. All three clusters were found to be severely contaminated with Fe, Pb, Cd, Cr, As and Hg in both the seasons. For all the three clusters, the mean values of heavy metal pollution (HPI) were found above the critical index in both the seasons.
Coupled shallow surface and subsurface flow
Interdisciplinary Center for Scientific Computing, Heidelberg University, Im Neuenheimer Feld 205, 69120 Heidelberg, Germany
Simulation of coupled surface and subsurface flow is important for understanding water budget on a variety of scales. The talk will review common models for surface and subsurface flow and then settle on a model that couples the diffusive wave approximation of the shallow water equations with shallow groundwater flow in the uppermost, unconfined aquifer. The model is discretized with a cell-centered finite volume scheme and solved with a fully-coupled Newton-multigrid method. Transport of dissolved substances is discretized with a higher-order discontinuous Galerkin scheme. It is demonstrated that large-scale simulations are possible through parallel computation on widely available multicore servers. However, with great compute capabilities comes the need for estimating model parameters from available data, a difficulty which is only be hinted at.
Hydrological Budget of three Himalayan Basins
A. P. Dimri
School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India.
Study of hydrological budget over Himalayan basins is important for decision making in flood risk and water resources management and identifying water sensitive areas. Temperature plays an important role in melting of snow. Climate change greatly influences moisture-temperature mechanism and feedback over the Indian Himalayan region (IHR). A case study of three important river basins (Indus, ganga, Brahmaputra) in the IHR has been performed. The objective is to establish the efficacy and thereby, applicability of using satellite-based data to estimate and determine the basin hydrology. Total Water Storage (TWS) consists of different components as precipitation, evaporation, runoff, snow water equivalent (SWE), soil moisture, ground water, etc. The individual components of TWS are analysed and determination of hydrological budget to be described. GRACE data provide MASCON L3 products of TWS anomalies. Seasonal trends are calculated using Mann Kendall test and Theil Sen estimator. Monsoon (Jun – Sep) dominates precipitation in Ganga and Brahmaputra river basins. Maximum decrease in TWS observed in postmonsoon (Oct-Nov) over Indus River Basin (IRB) while Ganga River basin (GRB) and Brahmaputra River Basin (BRB) show it in premonsoon (Mar-May).
Preliminary numerical groundwater modelling approaches for Swarnamukhi River and Kalangi River
Gossel, W.(1), Raju, N.J.(2)
(1) Martin-Luther-Universität Halle-Wittenberg, Applied Geology, Von-Seckendorff-Platz 3, 06120 Halle (2) School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067 India
In two case studies and in a generic approach the special conditions for numerical groundwater modelling in tropical settings and for saltwater intrusions in these areas and solutions to arising problems were focussed. In both case studies subsurface dams were a main issue: Seasonal water storage in the underground is a major aspect due to the climatic conditions and the lack of fertile soils outside the valleys. Saltwater intrusion threatens water supply at Kalangi River and all over the world and subsurface dams have shown to be a good prevention tool. Modelling groundwater flow and transport helps in both cases to understand and foresee connected processes and contaminations as well as possible solutions, e.g. in case of droughts or floods.
Impact of Bandhwari Landfill Leachate on Groundwater system in parts of National Capital Region, Delhi
Shilpi Gupta1 and N. J. Raju2
1 Scientist, Central Gound Water Board, DoWR, RD &GR, Ministry of Jal Shakti 2 Professor, School of Environmental Sciences, New Delhi
Landfill is a unit operation and most common form for final disposal of ‘Municipal Solid Waste’ (MSW) on land. MSW landfills can cause various types of pollution into all environmental components. Leachate generated from solid waste degradation can pollute soil and water severely. The negative impact of landfills can be reduced by applying protection and well design disposal site. Present study is carried out to understand the impact of Bandhwari landfill leachate on ground water system in the adjoining area. The Bandhwari land fill, with life span of seven years, lies in 92 acres of eco-sensitive land and protected forest zone. Prior to the operationalization of the landfill, the Gurgaon Municipal Corporation (GMC) was dumping untreated waste at the site, due to which almost 1/3rd of the total landfill site cannot be used. The estimated quantity of dumping waste (both solid waste and debris) is around two lakh tones. Around 200 samples were collected for four season and analysis have been done to understand the of landfill leachate on ground water quality in quartzite and alluvium terrain. The landfill leachate is percolating down through fractures and jointed quartzite, reaching to groundwater table at few places, and affecting groundwater quality in the area.
Tap or bottle? Survey data and experimental evidence on water consumption in Germany
Research Centre for Environmental Economics, Alfred-Weber-Institute for Economics, Heidelberg University
Bottled water has tremendous negative effects on the environment such as plastic waste and carbon dioxide emissions. As a consequence, many European countries aim to implement strategies to increase tap water consumption within their population. In Germany, the consumption of tap water is still relatively low despite high quality standards and easy access. Therefore, we investigate the current pattern of water consumption in Germany as well as potential underlying causes such as perception of quality and security, taste preferences, knowledge, lifestyle choices, political attitudes, and environmental concern in a large representative survey. Furthermore, we investigate in an online experiment whether advertising the quality and advantages of tap water can increase tap water consumption.
Methods for Large-Scale Bayesian Inversion for Groundwater Flow and Transport
Interdisciplinary Center for Scientific Computing, Heidelberg University
Groundwater remediation efforts require accurate simulations, which in turn require an adequate representation of the inherent variability and uncertainty of soil hydraulic parameters. Bayesian inverse methods enable us to obtain best estimates and corresponding uncertainties, based on prior expert knowledge and noisy state observations.
We present recent advances in maximum a posteriori parameter estimation, including a special preconditioned Conjugate Gradients method based on a six-term recurrence relation. We demonstrate how this approach leads to significant gains in efficiency over more traditional methods, and may additionally improve the accuracy of inversion results.
Sustainable Biochar- A Tool for Global Climate Change Mitigation, Soil Management and Water Treatment
School of Environmental Sciences, Jawaharlal Nehru University, New Delhi 110067, India
Global threats including climate change, land degradation, environmental contamination, and water shortages lead to economic, social and environmental damage. These need to be addressed to overcome the major disaster occurring now and in near future. Sustainable Biochar (BC) from biomass and wastes can be an environmentally-friendly option for carbon sequestration, soil fertility improvement, pollution remediation and agricultural by-product/waste recycling. Furthermore, IPCC recommended biochar as a carbon negative technology for climate change mitigation. An abundance of agricultural residues/byproducts exist and other crops that can easily be converted into bio-energy with bio-char as byproduct. The biochar produced can be burned or added into soils where its long-term duration, which can exceed centennial timescales, sequesters carbon while also improving soil fertility, structure and reducing fertilizer run-off. Use of biochars byproducts as green sorbents without further modification could also provide a value-added outlet. Sorption studies demonstrated that low surface area biochars have remarkably high capacities for contaminants remediation. This occurs due to permeation of water into the chars’ 3D structure where adsorption/coordination sites exist. Biochars swell in water due to oxygen-function present below pore surfaces and distributed throughout. This technology also provides additional benefits including clean energy, carbon sequestration and improved soil quality.
Impact assessment of textile effluents on groundwater and soil quality and associated health risk in industrial city Bhadohi, India
*Sughosh Madhav1 and N. Janarthana Raju2
1 Department of Civil Engineering, Jamia MIllia Islamia, New Delhi, India 2 School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India*
Bhadohi is a well-known textile centre in north India. A large number of textile industries are situated and functioning in Bhadohi city and surrounding areas. These industries produce a huge amount of textile effluents, which is discharged in an open sewer, ware lands and water bodies with and without appropriate treatment. The textile effluents cause heavy metal pollution in groundwater and soil in the vicinity of textile industries. To evaluate the heavy metal contamination, 35 groundwater samples and 11 soil samples were collected from Bhadohi environs. 48.5% of groundwater samples show a high concentration of iron. Based on the Heavy metal pollution index classification, 51% samples show low, 17 % samples show medium, and 32 % samples show with high heavy metal pollution index values. Target health quotient value of heavy metals were in the order of Pb> Mn> Cr> Cd> Cu> Fe> Zn> Ni. The average geoacumulation index value for all the metals was less than 0, except from Cr (0.542), Cd (0.232) and Zn (0.02). The mean pollution index for Fe (1.186), Mn (1.237) Cu (1.512), Zu (1.512), Pb (1.356), Cd (2.14), Ni (1.39), and Cr (2.343) is higher than 1, pointed out that medium pollution with these metals. Heavy metal contamination in groundwater and soil is more in the northern part due to the presence of textile industrial area and some dye effluents settling ponds in this region. Advance textile processing and adequate remediation measures are required for minimizing the heavy metal pollution in the study area.
Multi-temporal inventory of glaciers in Ladakh region between 1977 and 2019
Mohd Soheb, Jawaharlal Nehru University, New Delhi, India
We compiled four new glacier inventories of the Upper Indus Basin and Internal Drainage Basins around Ladakh region for 1977, 1993, 2009 and 2019 based on Landsat images. The inventory includes 2257 glacier, larger than 0.5 km2, covering an area of ~7923 ±212 km2, which is 14 and 11% less and 7% more than RGI 6.0, GAMDAM and ICIMOD glacier inventory estimations. The glacier area range between 0.5 to 862 km2, with most of them belong to the smallest size category (0.5-1 km2) but covers one of the least glaciated areas (~694 km2). Whereas the few largest glaciers >100 km2 (n = 7) cover one of the largest glaciated area of ~1879 km2. Shayok Basin house the highest number of glaciers and glaciated area; whereas, Tsokar Basin house the least. More than 70% of the glaciers are north-facing (NW-N-NE) and concentrated in higher elevation zones between 5000 and 6000m a.s.l.
Towards a socio-hydrological framework for the northwestern Himalaya
Marcus Nüsser1,2, Susanne Schmidt1, Dagmar Brombierstäudl1, Benjamin Kraus1,3, Juliane Dame1,2
1 Department of Geography, South Asia Institute (SAI), Heidelberg University 2 Heidelberg Center of the Environment (HCE), Heidelberg University 3 Institut für Technikfolgenabschätzung und Systemanalyse (ITAS), Karlsruhe Institut für Technologie
Socio-hydrological interactions in the Himalayan region range from meltwater-dependent irrigation systems on the local scale to cryosphere-related hazards including Glacial Lake Outburst Floods (GLOFs). These interactions are diverse and complex in nature and extend across different scales. Local communities who make use of meltwater potentials from the cryosphere for irrigated agriculture are increasingly facing situations of water shortage due to glacier retreat and deficiency of seasonal snow cover (see presentation by Schmidt et al.). These slow-onset developments are regularly experienced as limitations for regional land use systems and require new adaptation strategies to cope with seasonal as well as predicted future water scarcity. Examples of these adaptation strategies include implementation of water harvesting infrastructure such as ice reservoirs and construction of new irrigation channels to abstract meltwater. The contribution aims to develop a socio-hydrological framework for the northwestern Himalaya that may be used as a basis for more sustainable development pathways.
Sustainable Biochars for Sorptive Pharmaceuticals Removal
Manvendra Patel and Dinesh Mohan
School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, 110067
Developing adsorbents from locally available feedstocks for aqueous contaminants removal provides clean water supply and can reduce agricultural and forest waste residue load. In this study banana peel and water hyacinth was utilized for developing biochars and iron-oxide nano-particles coated biochar composites for aqueous pharmaceuticals adsorption. Developed biochars were characterized for physico-chemical, morphological and elemental properties. Batch sorption studies were applied to evaluate the effect of pH, temperature, biochar dosage, initial pharmaceutical concentration, biochar particle size, pyrolysis temperature, ionic strength, cations and anions. Developed biochars provide excellent sorption capacity for ciprofloxacin and acetaminophen sorption. Biochar composites have enhanced sorption capacity compared to pristine biochars. Thus, biochars developed from locally available abundant waste materials can be a sustainable solution.
Interlinkages among Health, Livelihood and Water Security in rural coastal Bangladesh
Mohammed Mofizur Rahman
Cologne University of Applied Sciences, Germany, and Anant Fellowship for Climate Action, India
Water security defined as the “availability of an acceptable quantity and quality of water for health, livelihoods ecosystems and agricultural production, coupled with an acceptable level of water-related risks to people, environments and economies”. Bangladesh has made substantial progress in alleviating water insecurity but still the challenges are multi-faceted. Nevertheless, ineffective water management, trans-boundary water sharing dispute with neighboring countries, insufficient governance and the lack of infrastructure adversely affects water security, while drinking water need is in competition with agricultural water demands. On the water quality front, the major concerns related to microbial contaminants, arsenic and salinity in groundwater. In addition, the large coastal population of Bangladesh are prone to suffer from water insecurity due to the simultaneous exposure to multiple water contaminants, slow onset hazards such as salinity intrusion and water logging, as well as rapid onset disasters such as cyclones and storm surges along with a high level of poverty. On average, annual floods inundate 20% of the country and can reach up to 70% during an extreme flood event. These floods severely disrupt water supply and sanitation conditions and allow the spread of various water-borne diseases such as cholera and diarrhoeal diseases. Both, floods and droughts, have implications for crop production and agricultural systems as well. Recent land-use changes such as conversion from agriculture to saline aquaculture may also lead to degradation of water resources. Decreased water quality also leads to increased adverse health outcomes. Therefore, the interrelationships among water security, health, well-being, livelihoods needs immediate attention, and wider discussion.
Modelling contribution of cryospheric components to the total discharge in Stok catchment, Ladakh, India
AL Ramanathan and Mohd Soheb
School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India
In Ladakh, snow and ice melt provide water for irrigation and domestic consumption to the downstream regions. Therefore, it is essential to understand the amount, timing, and temporal pattern of melt contribution of the region. Here we present a 17-year (2002-2019) discharge from the high-altitude Stok catchment of Ladakh region where snow and glaciers directly feed ~1500 people as per Census 2011. Moreover, the specific contribution from cryospheric components and rainfall to the discharge were also assessed. The method uses a degree-day based Glacio-hydrological model involving remote sensing, in-situ and reanalysis data. The modelled discharge was further validated against the observed discharge of 2018 and 2019. The modelled discharge is in good agreement with the observed discharge with R2 and RMSE of 0.83 (p < 0.01) and 1.1 m3 sec-1, respectively. The total discharge shows a large inter-annual variability with a mean discharge of ~39.55×106 m3 a-1 over 17 years. Total melt starts in February and peaks in August; whereas, snow and glacier melt peaks in May and August as observed through discharge contributions, respectively. Direct rainfall-runoff contributes relatively minimum to the total discharge. Snowmelt contributes the highest to the discharge (63%), followed by glacier melt (33%) and rainfall-runoff (4%). Total runoff shows an inverse relationship, whereas glacier melt runoff is directly associated with mass balance (MB). During high negative MB years, glacier melt contribution to total runoff surpasses snowmelt contribution a month earlier than near-balance MB years. In the Stok catchment, JJAS temperature and winter precipitation are the dominant controls.
Climate Change effects on Water Resources and Rainwater Harvesting Systems: Indian perspective
N. Janardhana Raju
School of Environmental Sciences, Jawaharlal Nehru University, New Delhi, India
Climate change inevitably bring about numerous environmental problems including alterations to the hydrological cycle which is already heavily influenced by anthropogenic activity. Erratic rainfall, population explosion, diminishing of water bodies due to urbanization, deterioration of water quality and over-extraction led to water crisis in many parts of Indian sub-continent. Effects of climate change on groundwater create difficulties such as long term decline in groundwater storage, severity of droughts and floods, mobilization of pollutants and saline water intrusion in coastal aquifers. In view of the water shortage for irrigation and domestic uses in parts of semi-arid Andhra Pradesh, subsurface dams preferred across ephemeral rivers with base flows to rise water levels as well as improve the socio-economic conditions through increased agricultural production. Community involvement is needed in water management as this improves local water harvesting systems for the sustainable development of any region.
Multiscale Methods for High Performance Uncertainty Quantification
Linus Seelinger und Robert Scheichl
Interdisciplinary Center for Scientific Computing, Heidelberg University
Mathematical models of complex real-world phenomena result in computational challenges, often necessitating the use of modern High Performance Computing (HPC) systems and therefore parallelization. When solving Uncertainty Quantification (UQ) problems on such models, these challenges only increase: Uncertainties in input data or (in case of inverse problems) in measurements essentially contribute to the overall dimensionality of the problem at hand.
We give a brief introduction to Uncertainty Quantification and present a parallelization strategy for multilevel Markov chain Monte Carlo. MLMCMC is a state-of-the-art, algorithmically scalable UQ algorithm for Bayesian inverse problems. We introduce a new software framework allowing for large-scale parallelism across forward model evaluations and the UQ algorithms themselves. Our software is released as part of the modular and open-source MIT Uncertainty Quantification Library (MUQ), and can be used with arbitrary physical models.
Finally, we give an outlook to a new software framework that allows easy coupling of any model code to MUQ and other UQ software packages, saving substantial development effort and supporting the collaboration of UQ and model experts.
Glaciers, snow and neglected forms of frozen water: Cryosphere components in the Transhimalaya of Ladakh
Susanne Schmidt1, Dagmar Brombierstäudl1, Stanzing Passang1, Juliane Dame1,2, Marcus Nüsser1,2
1 Department of Geography, South Asia Institute, Heidelberg University 2 Heidelberg Center of the Environment, Heidelberg University
In the semi-arid Transhimalaya of Ladakh, meltwater supply from the cryosphere is essential for irrigated agriculture. Different meltwater sources are used during the agricultural production period. Apart from glaciers and permafrost which meltwaters are used in summer, runoff from seasonal snow cover and aufeis is mostly used to bridge recurrent water scarcity in spring. While glaciers and snow cover are “visible” sources, easily detectable by optical remote sensing data, permafrost and aufeis are almost neglected in current research. The aim of the study is to inventory different components of the cryosphere and to analyse their seasonal variability and their general dynamics in the context of climate change. Based on different multi-temporal and multi-scale remote sensing data and techniques glacier changes are documented over long observation periods. The investigation of the seasonal snow cover is based on MODIS data and for the mapping of aufeis fields a time series analysis of Landsat data was conducted. This contribution reflects the environmental dimension of the socio-hydrological concept of Himalayan meltwater usage presented by Nüsser et al.
Contemporary and Holocene Glacier Characteristics in the Chandrabhaga Basin, Himachal Pradesh, India
Milap C. Sharma & Elora Chakraborty
Centre for the Study of Regional Development, Jawaharlal Nehru University, New Delhi, India
The Chandrabhaga basin, named after two headwater glacier fed rivers of Chandra and Bhaga, is a major basin to the Indus River system; currently hosting 46 (each with area >5 km2) valley glaciers covering over 589 km2, besides 769 other ice bodies covering an additional ~615 km2 geographical area of the basin. Bara Shigri, the largest glacier in the basin is of 26 km in length, occupying ~99.83 km2 of area, terminating almost at level with the trunk stream of Chandra at 3950 m above mean sea level. The 18 km long Samudri Tapu is the second largest, with an area of 75.65 km2, terminating at an altitude of 4200 m asl. The 27 km long Miyar glacier is a close third; having an areal extent of 73.67 km2, terminating at 4200 m a msl. Since present is the key to the past, we seek to assess the extents of these glaciers both in the present and in the history for a better comprehension of time and space factors. In order to understand the contemporary dynamics related to glaciers and climate parameters, we present a comprehensive analysis of related parameters for two decades that may shed some light on the present trend of ice cover in this region. Notably, response-time of glaciers in case of such changes may be in order of many 10s of decades, yet evaluating the present parameters and changes become necessary to project the future trend. We have mapped the glacial landforms for reconstructing glacier-climate evolutionary history of the basin, based on optical and radiocarbon ages mostly for the Holocene deposits, still well preserved as lateral and terminal moraines, along with the palaeo-lacutrine fills at several locations. Exposure ages of erratics and polished surfaces within the valleys are now being processed for further validation and precision to ascertain the closest-timings and style of deglaciation within the valleys. It is however, evident from the palaeo-landform records that all tributary glaciers which are now at or above 5 km2, once descended to the main trunk river floor, damming and creating lacustrine fills before being breached by the flowing main trunk rivers, namely, the Chandra, Bhaga and Miyar. Related terraces abound the entire basin. The Holocene expansion occurred in all tributary valley glaciers within a limit of ~4-6 km of the present snouts, constrained within ~08-10.0 ka BP (OSL). The retreat thereafter was gradual, evolving stream-lined features resembling drumlins at broader junctions where larger tributaries had once joined the trunk glacier. Existent visual records of glacial history in the recent past indicate that some of these glaciers have lost considerable mass over 150 years in the basin. On the other hand, radiocarbon ages of the bio-remains within confines of some of these glaciers have yielded ages of less than 01.0 ka, suggesting that these valley glaciers had attained their current positions long ago, probably prior to the dark-age warm period that permitted settled agriculture/herding at higher altitudes than the current livelihood activities practiced on lower terraces along the river valleys. It may be noted that waters needed for all purposes in the basin is from snow/glacier melt, be it the irrigation, hydel or the domestic supply. Prior to the Holocene event of expansion, still larger expansion has been constrained at ~85-87 ka BP (OSL) from the lacustrine sediments when gigantic glaciers of the two valleys confluenced to terminate at 3000m, occupying almost the entire valleys in the Chandrabhaga basin. Corresponding high river terraces in these valleys must have formed upon melting of this largest ice mass, fossilized all over the basin.
Nitrate Contamination in groundwater and its potential human health hazard in the south-eastern part of New Delhi
Krati Sharma and N.J Raju
Jawaharlal Nehru University, New Delhi, India
Groundwater resource management in arid and semi-arid environments requires systematic monitoring of groundwater quality periodically because many rural regions in alluvial plain facing scarcity of safe drinking water. A study was carried out to investigate the current status of groundwater quality, pollution load, and potential human health risk assessment in the south- eastern part of New Delhi. The study aims to understand how the increased availability of nitrate affecting the ecosystem, and human health. The result indicates that chloride, nitrate, fluoride level is at the alarming state. WQI and irrigation suitability were calculated to delineate the area unsuitable for drinking and irrigation purposes which will be helpful for the management of water resources. For the majority of groundwater samples across the clusters, substantial non-cancer health risk was observed. The hazard index value for children was higher compared to adults which indicate that children are more susceptible to health impairment in terms of non-carcinogenic health hazard. Therefore, there is an urgency to implement effective strategies to minimize the negative impact of nitrate pollution.
Water Conflict, cooperation and international water laws: With special reference to Ganga Brahmaputra Basin
CHRIST (Deemed to be University), Delhi-NCR
The conflict over water between India and Bangladesh has been and is again making headlines. The Ganga Brahmaputra Basin has survived diplomatic disputes for nearly sixty years, but current upstream water infrastructure projects have reignited difficulties. Climate change has deteriorating effects on Himalayan glaciers may increase the incidence of disasters and jeopardize populations' long-term water security. Under present usage and storage patterns, many communities in the Ganga Brahmaputra Basin confront water shortages.
Biochar, a panacea to safe drinking water: A discussion on its prospects in resolving water crises in India
Shaheed Rajguru College of Applied Sciences for Women, University of Delhi, Delhi -110096
Water is the most precious resource without which life is not possible. However, our improvidence to this resource has made it increasingly scarce. On average, one in nine-person does not have access to clean water. Such statistics have prompted United Nations to declare availability and the sustainable management of water and sanitation for all as its 6th Sustainable Development Goal (SDGs)1. Access to clean and safe drinking water is a human right. Moreover, a recent report on Depleting groundwater in India, predicted a possibility of 13 % of villages, losing 68 % of their cropped area by 2025 due to declining groundwater levels2. Across, several of the areas working towards managing and preserving water, biochar, and/or biochar based composites have a pivotal role to play whether in the home, the industry, water distribution systems, and/or in agricultural fields. The very high surface area, complex system of pores and channels, and functionalities in biochar protracted its longevity in holding the water2. Moreover, it also enables biochar to adsorb and/or, form bonds with the contaminants. These properties are ascribed to the slow pyrolysis process that causes physical, biological and chemical transformations in the biomass. These include the release of volatile matter, thermal cracking of cellulose, hemicellulose and lignin, and complex reactions involving their transformations, reformations, and rearrangements that give biochar its characteristic properties. Several studies have concluded the versatility of biochar in removing and mitigating different toxic contaminants, pollutants from the water and soil3. By taking examples from my previous research work on biochar, the paper aims to limelight its assurance and leverage over other technologies in mitigating the water crisis. It is concluded with conviction that biochar presents an affordable technological solution to purify water and wastewater. Thus, offering a future to technology in resolving water crises in India.
Impact assessment of faecal sludge disposal on groundwater and river water quality in Lucknow environs, North India
National Centre for Disease Informatics and Research (NCDIR), ICMR, Bengaluru, India
Faecal sludge (FS) is currently dumped in urban and peri-urban areas, creating significant threats to soil, surface water, and groundwater quality. The study’s goal is to characterize faecal sludge and analyse groundwater and river water quality as a result of waste disposal in Lucknow, one of India’s most polluted city. FS, groundwater, and river water were sampled from the study area in the post-monsoon season to achieve the goal. Piper diagram, Gibbs diagram, Water Quality Index (WQI), Wilcox diagram, and US Salinity Laboratory (USSL) diagram were used to evaluate groundwater and river water data. According to the findings, the FS sample contains significant levels of electrical conductivity, cations, and anions. Piper diagram demonstrates that dominance of the anions is mainly HCO3 in groundwater and river water. Gibbs' graphic displays weathering of rocks over which water flows as the primary source of soluble ions. According to the WQI, groundwater samples were categorised as excellent, good, and poor, while river water samples were categorised as good, poor, extremely poor, and unfit for drinking. The bulk of the samples are appropriate for irrigation in groundwater and river water, according to the Wilcox and USSL figure. The study concludes that open waste dumping has an impact on groundwater quality in solid waste disposal and slum areas, while effluent discharge increases the pollution load of river water downstream.
Groundwater quality deterioration under changing sea level along South West coast of India
Centre for the Study of Regional Development, Jawaharlal Nehru University, New Delhi, India
Groundwater along the coast is vulnerable to rising sea level l leading to salt water Intrusion into the coastal aquifer systems. Consequently, the groundwater quality deteriorates and makes it unusable for household use, irrigation and other economic activities for the coastal communities. Therefore, this paper is an attempt to analyse the modifications in the shoreline and concurrent deterioration in groundwater quality along the coast of Ernakulam district, Kerala, South West of India. Tide gauge data is used to determine the sea level change and satellite remote sensing data is deployed to estimate the shoreline changes. Digital Shoreline Analysis System (DSAS) is used to determine degree of erosion and accretion along the coast, which indicates the locations of the impact of sea level rise. The physical and chemical properties of groundwater are determined for 46 samples collected from open wells along the coasts and banks of backwater. Different ionic ratios are computed to assess the groundwater quality at the sampling locations. Sodium percentage (Na %) and potential salinity were computed for determining salt-water intrusion and the suitability of the groundwater usage for domestic and irrigation purpose. Spatial variations of pH, EC, TDS and ionic ratios are assessed in the GIS environment through IDW interpolation. Findings indicate a rising trend in sea level at the rate of 0.23 m/yr along the coast of the study area. Shoreline accretion and erosion was also observed at different locations along the coast, though the rate of change varied across the shoreline. In general, water has shown slight alkaline nature, with pH varying from 7.2 to 8.2 at some locations particularly along the coast. Higher values of EC and TDS were also observed along the coastal aquifer. Sodium percentage (Na %) and potential salinity suggest presence of salt water. However, groundwater in majority of the areas especially away from the coast is good for domestic and irrigation uses. The groundwater quality changed with rainfall intensity and distribution on annual basis.
Arsenic contamination of groundwater - Spatial and temporal impact in Bangladesh and different sustainable remediation approaches
Institute of Geography, Heidelberg University, Im Neuenheimer Feld 348, 69120 Heidelberg
In Bangladesh and West Bengal (India), naturally occurring high arsenic concentrations in groundwater pose a continuous threat to the population. Most families use untreated groundwater for drinking water supply, which regionally often exceeds the 10µg/l threshold suggested by the World Health organization, causing diverse negative health effects. Furthermore, groundwater is locally used for irrigation, thus contaminating soils and plants and diminishing rice yields.
In our interdisciplinary project team between Earth Sciences (Dr. Martin Maier), Geography (Charlotte Stirn) and Engineering (Laya Raj) we are investigating the causes of arsenic release in Bangladesh. Therefore, we conducted comprehensive field studies to understand processes of Arsenic release in different parts of Bangladesh and tested a remote sensing approach, based on Radar data, to distinguish natural (monsoonal, flooding) and anthropogenic (irrigation, standing water) causes for arsenic mobilizing conditions. Furthermore, we are developing different remediation approaches. Our aim is to provide sustainable, sophisticated solutions for arsenic removal at (household/centralised level). Most filter technologies on the market can’t efficiently remove arsenic in drinking water to attain WHO standards but only clean small amounts of water, are expensive and generate large amounts of toxic waste (exhausted filter material).
We will jointly present the results of our recent research:
- On the impact of landuse on geochemical conditions and arsenic release.
- Sustainable usage of different adsorber media for arsenic removal in drinking water, including recycling approaches, multiple usage and harmless storage of waste.
- Electrocoagulation for the treatment of larger water quantities and pretreatment of drinking water.
Groundwater dynamics of Urban and Rural environment in Indo-Gangetic plain, India-Key issues and remedial measures
Department of Geology, Aligarh Muslim University, Aligarh, India
Indo-Gangetic plain (IGP) forms one of the major physiographic units which is also the biggest repository of fresh groundwater resources in India. IGP supports extensive agricultural production. Population growth and industrialization has changed the landuse pattern significantly. Cities within IGP are witnessing huge population migration from rural areas that pose tremendous pressure on shrinking groundwater resources. Extensive irrigation, use of fertilizers, neo-urban centers and resultant landuse patterns have impacted the Groundwater dynamics in qualitative and quantitative terms. Over-abstraction and changes in landuse pattern impose additional stress on groundwater quality as well as quantity, thereby resulting into a water level decline of approx. 0.4 to 1 m/year and excessive concentration of certain elements like Na, Cl, NO3, SO4, hardness and heavy metals. Groundwater bears signatures of ion-exchange, rock-water interaction and influences from irrigation returns and landuse activities. The work carried out in different parts of Upper Ganga Plain including hydro-chemical characteristics, aquifer vulnerability and groundwater flow modeling will be presented.