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India Mark‐II hand pump was successfully modified in the present study so as it can serve as an efficient tool for the disinfection of the borewell water. This modified Hand Pump works on the principle of hydrodynamic cavitation, which can potentially disrupt the bacteria and fungi rendering them unviable. The reduction in organic carbon was also found in the borewell water. However hydrodynamic cavitation technology was induced first time in the hand pump for the disinfection of groundwater. Several field trials were carried out at different field locations in Maharashtra, India to validate the modifications of this novel technology. This modification does not require any additional energy to purify the water and is found to have yielded > 90% water disinfection. The third‐party analysis was carried out from NABL certified microbiological laboratories which showed that all Gram negative pathogens were successfully destroyed. Therefore, the people who rely on hand pumps across the world for groundwater pumping will be able to access quality potable water and can be rescued from pathogen‐based waterborne diseases. Hand pump cavitation will be a water disinfection milestone in the emerging era of ecologically benign, innovative, and cost‐effective rural water disinfection technology. [ABSTRACT FROM AUTHOR]

Bacteriological contamination in drinking water is known to be responsible for the spread of various waterborne diseases. Although chlorine is frequently used as disinfectant in water treatment, low-cost disinfecting technologies in the villages of developing and under-developed countries are not yet successfully implemented. This study contributed in designing a simple and inexpensive water disinfection unit to produce chlorine from the naturally available dissolved chloride of groundwater by electrochlorination, using inert and cheap graphite electrodes. Laboratory-based experiments were performed in both batch and continuous flow reactors to study the effect of time, current, electro charge loading (ECL), and surface area of electrodes in chlorine generation and bacterial inactivation. Controlled experiments in continuous mode in the absence of chlorine further indicated the possibility of partial inactivation of bacteria under the influence of the electric field. Finally, a treatment unit with drilled anodes, and undrilled cathode electrodes, in continuous flow set-up was installed in four schools of four different villages in West Bengal, India. An average residual chlorine concentration and removal efficiency of total coliform in the designed systems were determined as 0.3 ± 0.07 mg/L, and 98.4% ± 1.6%, respectively. [ABSTRACT FROM AUTHOR]

In India, majority of the generated municipal solid waste (MSW) was dumped in poorly managed landfills and dumpsites over the past decades and is an environmental and health hazard. Landfill mining is a promising solution to reclaim these sites along with the recovery of resources (materials and energy). During landfill mining operations, the combustible fraction is one of the major components recovered and needs proper management for maximizing resource recovery. For the identification of appropriate resource recovery options, knowledge of the physicochemical characteristics is required. The present study aims to assess the depth-wise change in the composition of legacy waste and the physicochemical characteristics of the combustible fraction. Furthermore, a material flow analysis considering the incineration of combustible fraction was performed to estimate the energy generation potential and the associated greenhouse gas (GHG) emissions. The results of the compositional analysis of dry legacy waste revealed that the fine fraction (<4 mm soil-like material) was dominating with a share of 36%. The depth-wise analysis showed a decrease in the calorific value with increasing landfill depth, while no specific trend was observed for the other parameters analyzed, including proximate and ultimate analysis, and chlorine content. The material flow analysis performed for 100 tonnes of wet legacy waste indicated that 52 tonnes of waste is combustible fraction. The GHG emissions through incineration of one tonne of dry combustible fraction would be 1389 kg CO 2 -eq, with 1125 kWh of electrical energy generation potential. [Display omitted] • Changes in physicochemical characteristics with landfill depth were assessed. • The legacy waste had a high share of combustible fraction accounting for 52%. • The combustible fraction was found to be suitable for WtE treatment and use as RDF. • One tonne of legacy waste showed a potential to generate 428 kWh of electricity. • Incinerating one ton of combustible waste can emit 1389 kg CO 2 -eq of GHG emissions. [ABSTRACT FROM AUTHOR]

India faces high incidents of waterborne disease outbreaks owing to their limited access to safe drinking water. In many ways, the effort to improve the quality of drinking water is performed, and it has been keenly monitored. Among those, the disinfection of drinking water is considered a necessary and important step as it controls the microbial population. Chlorination is the most practiced (greater than 80%) disinfection process in India, and it is known to generate various disinfection byproducts (DBPs). Although the toxicity and trend of DBPs are regularly monitored and investigated in most countries, still in India, the research is at the toddler level. This review summarizes i) the status of drinking water disinfection in India, ii) types of disinfection processes in centralized water treatment plants, iii) concentrations and occurrence patterns of DBPs in a different region of India, iv) a literature survey on the toxicity of DBPs, and v) removal methodologies or alternative technologies to mitigate the DBPs formation. Overall, this review may act as a roadmap to understand the trend of disinfection practices in India and their impacts on securing the goal of safe drinking water for all. [Display omitted] • Chlorination is a widely used disinfection treatment in India. • Proper optimization of chlorine dosage is lacking in many water treatment plants (WTPs). • The governmental program acts as a forum to identify hotspots of microbial contamination. • In drinking water, trihalomethanes are the only regulated DBPs. • Halo acetic acids and nitrogen-based DBPs are emerging DBPs in Indian WTPs. [ABSTRACT FROM AUTHOR]

Household water treatment systems play an important role in safe drinking water supply in India as safety barrier at point of use and contribute to improved public health on short and medium term. In this study, three household water purifiers that based on different principles were investigated in order to determine whether and under which conditions they can safeguard the microbial safety of drinking water. The water purifiers consisted of the following treatment trains: (i) activated carbon (AC), ultrafiltration (UF) and reverse osmosis, AC and UV irradiation; (ii) AC and UF, and (iii) AC, passive chlorine dosage and AC. They were examined in a two-phase challenge test using bacteria (Escherichia coli) and bacteriophages (MS2) in a laboratory environment. Under normal operation conditions filtering tap water, mean microbial reductions of 4–6 log10 and 0–3 log10 for E. coli and MS2 phages, respectively, were observed that therefore partly comply with WHO requirements. Reduction of protozoa (Cryptosporidium oocysts) was estimated based on size exclusion or chlorine exposure to be ≥2 log10 (membrane-based size exclusion) and <2 log10 (chlorine-based disinfection), respectively. To further determine their applicability for filtering water sources with higher pollution load, tap water with increased loads of organic and suspended matter simulating turbid river water (which is beyond the intended use of the systems) was studied. Only the multi-stage treatment was able to remove organics and turbidity to ≥89%. Both tested membrane-based systems suffered from rapid and severe irreversible fouling when challenged with high turbidity whereas the chlorine-based system maintained the production rate, however, at the expenses of a lower physicochemical quality. Hence, none of the tested systems was able to produce water of satisfying physicochemical and microbial quality at sufficient quantities from raw water with turbid river water quality. Therefore, it is suggested introducing mandatory standardized testing protocols and certification of household water purifiers specifying the usage conditions. [ABSTRACT FROM AUTHOR]

SWINGS was a cooperation project between the European Union and India, aiming at implementing state of the art low-cost technologies for the treatment and reuse of domestic wastewater in rural areas of India. The largest wastewater treatment plant consists of a high-rate anaerobic system, followed by vertical and horizontal subsurface flow constructed wetlands with a treatment area of around 1,900 m2 and a final step consisting of solar-driven anodic oxidation (AO) and ultraviolet (UV) disinfection units allowing direct reuse of the treated water. The implementation and operation of two pilot plants in north (Aligarh Muslim University, AMU) and central India (Indira Gandhi National Tribal University, IGNTU) are shown in this study. The overall performance of AMU pilot plant during the first 7 months of operation showed organic matter removal efficiencies of 87% total suspended solids, 95% 5-day biological oxygen demand (BOD5) and 90% chemical oxygen demand, while Kjeldahl nitrogen removal reached 89%. The UV disinfection unit produces water for irrigation and toilet flushing with pathogenic indicator bacteria well below WHO guidelines. On the other hand, the AO disinfection unit implemented at IGNTU and operated for almost a year has been shown to produce an effluent of sufficient quality to be reused by the local population for agriculture and irrigation. [ABSTRACT FROM AUTHOR]

To ascertain the quality of drinking water being supplied and maintained, it is necessary to conduct water quality surveillance for evolving suitable strategy for future planning. In the present investigation, water quality was monitored in treatment plants, service reservoirs, and at consumer ends in three seasons to assess the baseline water quality status at Shillong in Meghalaya. There are three water treatment plants at Shillong namely Umkhen, Mawlai and GSWS with design capacities of 1.5, 3.4 and 34 Million liter per day (MLD) respectively. Each treatment plant is having rapid sand filtration followed by disinfection. The study reveals that the physico-chemical parameters of water quality at consumer end meets Indian drinking water quality standards (BIS ) after conventional treatment followed by disinfection, whereas the bacteriological parameters for raw water sources exceed the permissible limit indicating the treatment need for drinking purposes. Throughout year the average feacal coliform contamination at service reservoir and to consumer end were found as 44 to 156 CFU/100 ml which may be attributed to the general management practices for maintenance of service reservoirs and the possibility of en route contamination. [ABSTRACT FROM AUTHOR]

Background: Solar radiations improve the microbiological quality of water and offer a method for disinfection of drinking water that requires few resources and no expertise and may reduce the prevalence of diarrhea among under-five children. Aims and Objectives: To find out the reduction in the prevalence of diarrhea in the under-five children after consumption of potable water treated with solar disinfection method. Materials and Methods: This was a population-based interventional prospective study in the urban slum area of Mazegoan, Jorethang, south Sikkim, during the period 1st May 2007 to 30th November 2007 on 136 children in the under-five age group in 102 households selected by random sampling. Main outcome measure was the assessment of the reduction of the prevalence of diarrhea among under-five children after consumption of potable water treated with solar disinfection method practiced by the caregivers in the intervention group keeping water in polyethylene terephthalate (PET) bottles as directed by the investigators. The data were collected by the interview method using a pre-tested questionnaire prepared on the basis of socio-demographics and prevalence of diarrhea. The data were subjected to percentages and chi-square tests, which were used to find the significance. Results: After four weeks of intervention among the study group, the diarrhea prevalence was 7.69% among solar disinfection (SODIS) users, while 31.82% prevalence was observed among non-users in that period; the reduction in prevalence of diarrhea was 75.83%. After eight weeks of intervention, the prevalence of diarrhea was 7.58% among SODIS users and 31.43% among non-users; the reduction in diarrhea was 75.88% in the study group. The findings were found to be statistically significant. Conclusions: In our study, we observed that the prevalence of diarrhea decreased significantly after solar disinfection of water was practiced by the caregivers keeping potable water in PET bottles in the intervention group. [ABSTRACT FROM AUTHOR]

High rates of mortality and morbidity due to water-borne diseases are well known in India. Serious degradation of water quality in urban India has often been attributed to indiscriminate disposal of sewage and industrial effluents into surface water bodies. Although some degree of intervention in terms of chlorination and monitoring of water quality exists in major cities and towns, rural India, which constitutes the bulk (70%) of the population, is usually deprived of such interventions. The population in rural India is mainly dependent on the groundwater as a source of drinking water. As a quality concern the groundwater is often found to be contaminated with fluoride, arsenic, iron and salts. In recent years, fluorosis has emerged as major public health issue in rural India. At the technical level, some progress has been made in the development and use of field-level diagnostic kits. Decentralization of health-related monitoring at the villages needs to be institutionalized and this requires capacity development at all levels. This article discusses the various components that impact effective water quality management in rural India. Experience suggests that redesigning of data management programme at village, district and at national level, upgradation of district-level laboratories and addressing technical, legal and institutional components should become the first steps in achieving effective water-quality management and providing better health to millions of people living in rural India. [ABSTRACT FROM AUTHOR]

Hospital effluents are loaded with pathogenic microorganisms, partially metabolized pharmaceutical substances, radioactive elements, and other toxic substances. Such effluents if not treated properly can damage the natural environment and create a biological imbalance. This paper points out the areas of concern for hospital wastewater disposal and reports the findings of a limited physico-chemical study of treatment options for hospital effluents conducted at Christian Medical College and Hospital, Vellore, Tamil Nadu. The effluent collected was checked for conventional parameters and subjected to coagulation experiments. The raw and settled effluents were coagulated with FeCl3, filtered and disinfected. Physico-chemical treatment seems to be an attractive option for the cost-effective disposal of hospital effluents. The results of this study call for further detailed study in this area. [Copyright &y& Elsevier]