Cauvery row: let us dive into facts and figures

Recent developments over the Cauvery waters have gripped the public imagination like no other contemporary environmental issue. The following WhatsApp message showed up on a group a few days ago: ‘The problem with the Kaveri (sic) issue is lack of facts, more of emotion and opinion. Let’s look at the facts and figures.

Reimagining the past – use of counterfactual trajectories in socio-hydrological modelling: the case of Chennai, India

The developing world is rapidly urbanizing. One of the challenges associated with this growth will be to supply water to growing cities of the developing world. Traditional planning tools fare poorly over 30–50 year time horizons because these systems are changing so rapidly. Models that hold land use, economic patterns, governance systems or technology static over a long planning horizon could result in inaccurate predictions leading to sub-optimal or paradoxical outcomes. Most models fail to account for adaptive responses by humans that in turn influence water resource availability, resulting in coevolution of the human–water system. Is a particular trajectory inevitable given a city’s natural resource endowment, is the trajectory purely driven by policy or are there tipping points in the evolution of a city’s growth that shift it from one trajectory onto another

Death knell for citizen-led lake governance

Bengaluruhas become a bit notorious globally as videos of Bellandur lake catching fire and its froth blocking roads over the past couple of years have gone viral. But Bengaluru’s lakes areal so famous for another reason: the enormous citizen activism that has led to the protection, rejuvenation and beautification of many of its lakes, and the continued citizen efforts to save and revive the remaining ones

Why we must have water budgets: If we run out of groundwater, millions of people will be left without any means to sustain themselves

The protest by farmers in Chikballapur recently, over the scarcity of drinking water, received extensive news coverage as it halted Bengaluru in its tracks after key highways were blocked. Interestingly, very little of that coverage was devoted to the groundwater crisis that underpins the problem in such regions

Managing our lakes and sewage

On the morning of March 7, the walkers and joggers at Bengaluru’s Ulsoor lake were shocked to see thousands of dead fish piled up its banks. The local corporator blamed the fisherfolk, the chairman of Karnataka State Pollution Control Board (KSPCB) asked for time to investigate, and residents blamed all government agencies. Solutions proposed ranged from running motorboats and releasing ducks, to banning fishing and releasing enzymes for lake cleanup

Waste Not, Want Not: The Potential for Urban Water Conservation in California

The largest, least expensive, and most environmentally sound source of water to meet California's future needs is the water currently being wasted in every sector of our economy. This report, "Waste Not, Want Not," strongly indicates that California's urban water needs can be met into the foreseeable future by reducing water waste through cost-effective water-saving technologies, revised economic policies, appropriate state and local regulations, and public education

Addressing water stress through wastewater reuse: Complexities and challenges in Bangalore, India

Wastewater reuse is an important adaptation option for mitigating water stress in rapidly growing urban centres. But, wastewater reuse is easier said than done, particularly in developing countries. The task becomes even more challenging when one takes a basin-level perspective. We illustrate these challenges by studying the Vrishabhavathy River in Bangalore, India, which carries almost half of the city’s wastewater. First, we find that the sewage treatment plant (STP) located on this river does not function efficiently and no positive impact of effluent discharge on river water quality was observed. Second, while the Sewerage Board has implem ented conventional centralized sewage treatment and proposed its expansion and even larger scale projects, decentralized wastewater treatment, advocated by many civil society groups, may be more cost effective. Options at all scales, however, face several institutional challenges in implementation. Third, while untreated wastewater is a health hazard for downstream farmers using this water for irrigation, substantial wastewater recycling upstream would have a negative impact on their livelihoods by reducing the quantity of water available for irrigation. In addition, as the Vrishabhavathy is a tributary of the inter-state river Cauvery, reduced flows might impact on inter-state water sharing commitments complicating matters further. Realizing the potential of wastewater reuse in Bangalore will thus require techno-institutional integration and thinking at a basin scal

Linear growth and fat and lean tissue gain during childhood: associations with cardiometabolic and cognitive outcomes in adolescent Indian children

Background: We aimed to determine how linear growth and fat and lean tissue gain during discrete age periods from birth to adolescence are related to adolescent cardiometabolic risk factors and cognitive ability.Methods: Adolescents born to mothers with normal glucose tolerance during pregnancy from an Indian birth cohort (N = 486, age 13.5 years) had detailed anthropometry and measurements of body fat (fat%), fasting plasma glucose, insulin and lipid concentrations, blood pressure and cognitive function. Insulin resistance (HOMA-IR) was calculated. These outcomes were examined in relation to birth measurements and statistically independent measures (conditional SD scores) representing linear growth, and fat and lean tissue gain during birth-1, 1–2, 2–5, 5–9.5 and 9.5–13.5 years in 414 of the children with measurements at all these ages.Results: Birth length and linear growth at all ages were positively associated with current height. Fat gain, particularly during 5–9.5 years was positively associated with fat% at 13.5 years (0.44 SD per SD [99.9% confidence interval: 0.29,0.58]). Greater fat gain during mid-late childhood was associated with higher systolic blood pressure (5–9.5 years: 0.23 SD per SD [0.07,0.40]) and HOMA-IR (5–9.5 years: 0.24 [0.08,0.40], 9.5–13.5 years: 0.22 [0.06,0.38]). Greater infant growth (up to age 2 years) in linear, fat or lean components was unrelated to cardiometabolic risk factors or cognitive function.Conclusion: This study suggests that factors that increase linear, fat and lean growth in infancy have no adverse cardiometabolic effects in this population. Factors that increase fat gain in mid-late childhood may increase cardiometabolic risk, without any benefit to cognitive abilities

Contribution of sewage treatment to pollution abatement of urban streams

In this study, we assessed the efficiency and effectiveness of the Vrishabhavathy Valley Treatment plant (VVTP) in Bengaluru city, which is the oldest STP in the city. Since VVTP treats both raw sewage and polluted river water, with the latter constituting 80% of the influent, we sampled water quality at locations upstream and downstream of the plant to evaluate overall efficacy as well

Why is the Arkavathy River drying? A multiple-hypothesis approach in a data-scarce region

Water planning decisions are only as good as our ability to explain historical trends and make reasonable predictions of future water availability. But predicting water availability can be a challenge in rapidly growing regions, where human modifications of land and waterscapes are changing the hydrologic system. Yet, many regions of the world lack the long-term hydrologic monitoring records needed to understand past changes and predict future trends. We investigated this “predictions under change” problem in the data-scarce Thippagondanahalli (TG Halli) catchment of the Arkavathy sub-basin in southern India. Inflows into TG Halli reservoir have declined sharply since the 1970s. The causes of the drying are poorly understood, resulting in misdirected or counter-productive management responses. Five plausible hypotheses that could explain the decline were tested using data from field surveys and secondary sources: (1) changes in rainfall amount, seasonality and intensity; (2) increases in temperature; (3) groundwater extraction; (4) expansion of eucalyptus plantations; and (5) fragmentation of the river channel. Our results suggest that groundwater pumping, expansion of eucalyptus plantations and, to a lesser extent, channel fragmentation are much more likely to have caused the decline in surface flows in the TG Halli catchment than changing climate