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India, being a developing country, faces big challenges in ensuring water, sanitation, and hygiene (WASH) for all. This case study presents the performance evaluation of a large wastewater management and sanitation-related infrastructure in a metropolitan city in North India. "Dravyavati River Project" is the major sanitation program of the water-stressed Jaipur city based on the concept of river rejuvenation of the long-lost Dravyavati River which flows across the city. The project envisages integrated urban water management such that it aims at the collection and treatment of wastewater (sewage network and treatment plants), safe disposal, ensuring continuous unpolluted flow, geological and ecological integrity to strengthen public health, to reduce the impact of water stress on the total water cycle by promoting groundwater recharge, and improvement in biodiversity. The technical assessment is based on the primary and secondary data collection of field samples and laboratory analysis of influent and effluent samples collected from the five sewage treatment plants (STPs). The results suggest that the project has largely delivered the envisaged environment, public well-being, and ecological and socioeconomic benefits, but there are substantial gaps in the conceived outputs and actual performance. The challenge lies in bridging these gaps and overcoming operational inefficiencies to ensure the sustainability of the Dravyavati River rejuvenation. [ABSTRACT FROM AUTHOR]

Pharmaceuticals compounds are the emerging contaminants known for their refractory and environmental persistence, which pose threat to flora and fauna. In the present study, the occurrence and possible contamination sources of four drugs, namely paracetamol, diclofenac, salbutamol and ceftriaxone in wastewater of Mysuru, India, were investigated. The said pharma compounds were analyzed in the effluent of select health care establishments and municipal wastewater treatment plant (MWWTP). The results revealed that diclofenac was omnipresent in all the samples with the peak concentration of 4.2 µg/mL, whereas salbutamol and ceftriaxone were in the range of 0.7–18.7 µg/mL and 1.25–29.15 µg/mL, respectively. In addition, paracetamol was detected only at the inlet of MWWTP with a concentration of 4.6 µg/mL. Surprisingly, the presence of relative amounts of these drugs in the treated water released from MWWTP was observed. Further, the 'risk quotient method' for ecological risk assessment was adopted to assess the magnitude of risk toward aquatic species. Next, the study employed the concept of citizen science to gather information on disposal and management methods of unused and expired medications at household and health care centers. This survey revealed that hospital discharges and community disposal of unused medicines contributed to incidence of pharmaceutical compounds in the local environment. Finally, a precise perspective and future challenge for the safe management of drugs are presented. [ABSTRACT FROM AUTHOR]

The first full-scale down-flow hanging sponge (DHS) reactor applied to post-treatment of effluent from an upflow anaerobic sludge blanket (UASB) reactor for the treatment of municipal sewage was evaluated, with emphasis on nitrification. The full-scale DHS reactor was successfully operated at a hydraulic retention time of 1.5 h for over 1800 days in India. The DHS reactor produced effluent with 6 mg L −1 ammonium nitrogen, corresponding to 79% removal efficiency. The total nitrogen removal by the DHS reactor was 65%. The high process performance of the DHS reactor was supported by its distinctive characteristics of (1) high dissolved oxygen of 5.4 mg L −1 in the DHS effluent without forced ventilation, (2) dense retained sludge in the range of 23–46 gVSS Lsponge −1 , and (3) adequate sludge activity of 52 mgN gVSS −1 day −1 for nitrification. The full-scale experiment has proven that the DHS reactor has practical applicability to developing countries. [ABSTRACT FROM AUTHOR]

This article evaluates the performance of 10 large scale upflow anaerobic sludge blanket (UASB) sewage treatment plants (STP) located in semi-tropical areas, 7 plants were located in Brazil, 2 in India and 1 in the Middle East. In addition to the UASB, essential functional units of the STP which potentially impact on the UASB are also evaluated. Most grit removal systems were performing adequately, however in one plant very little grit was being removed. This could have serious implications for the performance of the plant as in a relatively short period of time the reactors could become full of grit. The performance results obtained in this study (COD, BOD and TSS removal efficiencies) are compared to the results of recent literature publications and also to the results of some early pilot and full scale studies. The results found here are broadly similar to those result reported in the recent literature but show a lower performance in comparison with the early pilot scale plants. Factors such as improper design, poor operating procedures, insufficient maintenance and the presence of high sulphate concentrations have been identified as the main reasons for the lower performance. [ABSTRACT FROM AUTHOR]