Towards sustainable lake restoration.

Sustainable lake restoration has been introduced recently as a strategy to address ecological, economic, and social challenges in nutrient management. The strategy would benefit at least 40 % of the world's lakes through addressing eutrophication, and the impact becomes even broader if we consider the complex nature of eutrophication (its linkage to multiple environmental problems). This approach involves: 1) demonstrating broader social and economic benefits, 2) integrating circular economies, and 3) directly engaging local communities in co-developing restoration goals, targets and monitoring.

The benefits of restoring urban lakes in the tropics.

Lake restoration in developing economies, particularly in the tropics, is a major challenge given the severe levels of pollution from untreated wastewater and the warm climate conducive to microbial and algal growth. Restoration goals are often ill-defined or unachievable. Here we describe the successes that can be achieved through a control, compared with intervention case study of the two urban lakes in Bengaluru, India, one of the world's largest and fastest growing mega-cities.

Environmental surveillance of antimicrobial resistance in a rapidly developing catchment.

Development and spread of AMR from various sources such as hospitals, pharmaceutical industries, animal farms and human habitations is not well understood. We conducted a pilot study to assess the prevalence of AMR by taking a case of rapidly developing catchment in Western India. For this, we selected four sub-catchments/regions with a dominant source of antibiotics, viz.

A multi-pronged approach to source attribution and apportionment of heavy metals in urban rivers.

Heavy metal (HM) contamination of water bodies is caused by both first generation (industries) and second generation (distributed sources, domestic sewage, sediments) sources. We applied a multi-pronged approach to quantify the contribution of first and second generation sources to the HM load in a stream located in an industrialised catchment. We found that, despite strict regulation, first generation sources contributed significantly to the HM load (60%-80%), showing the ineffectiveness of current regulation.

Sustenance of Himalayan springs in an emerging water crisis.

Springs are a significant source of high quality and perennial freshwater supply for remote communities and sustain rich biodiversity and ecosystems in the Himalayas. About 60-70% of the Himalayan population directly depends on springs to meet their domestic and livelihood needs. Despite that, decline in approximately 60% of low discharge springs have been reported in the last couple of decades.

A novel approach to baseline water quality assessment at local and catchment scale: a case study from Berambadi, India.

Optimal design and maintenance are necessary for the sustainability of wastewater treatment systems. In this study, we present the outcome of a novel approach to baseline assessment conducted prior to the design and deployment of a decentralized wastewater treatment system at a school in rural India. The baseline water quality monitoring protocol was deployed to assess (a) the quality and quantity of wastewater (greywater and blackwater) flows from the school and (b) the status of surface water and groundwater quality in the catchment.

Greenhouse gas budgets of severely polluted urban lakes in India.

Inland waters are important sources of greenhouse gases and emissions from polluted subtropical systems may be contributing to the observed global increase in atmospheric methane concentrations. Here we detail a scoping study where dissolved concentrations of greenhouse gases methane (CH), carbon dioxide (CO) and nitrous oxide (NO) were measured in two contrasting urban lakes in Bangalore (Bengaluru), Karnataka, India, from June 2018 to February 2020. Bellandur Lake is a severely polluted system whilst Jakkur Lake has been subject to partial restoration via treatment of organic matter inputs.

Sustainable water resources through harvesting rainwater and the effectiveness of a low-cost water treatment.

Increases in world population and climate change are some of the pressures affecting water resources for current and future water availability. The variability in water availability can reduce agricultural yields, food supplies and potentially leads to malnutrition and spread of diseases in water-poor countries. Even some water-rich countries can experience prolonged periods of dry weather, causing a drop in water reservoirs levels, forcing more restricted water resources management.

Provisional green infrastructure: transdisciplinary approaches to address contamination in urban streams.

Surface water contamination has emerged as an area of major concern in rapidly growing cities in the Global South, including and especially in the Indian megacity context. We argue here that nallahs (open drainage channels in Indian megacities) should be more widely recognized as a potential locus of intervention. These combined stormwater and wastewater networks offer opportunities for flexible, frugal and inclusive retrofits to improve surface and groundwater quality.

Assessing local materials for the treatment of wastewater in open drains.

In the present study, three low-cost filter aggregate materials were tested and compared for organic matter and fecal coliform (FC) removal at the laboratory scale. Setups were subjected to synthetic wastewater at two hydraulic loading rates (HLR), i.e.

Efficiency evaluation of sewage treatment plants with different technologies in Delhi (India).

Physical, chemical and microbiological efficiencies of Sewage Treatment Plants (STPs) located in Delhi's watershed in context of different treatment technologies employed in these plants have been determined. There were in all seventeen STPs treating domestic wastewater which were studied over a period of 12 months. These STPs were based on Conventional Activated sludge process (ASP), Extended aeration (Ex.