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An important aspect of economic considerations is the routing and safety of hydraulic storage facilities such as dams for extreme probable water flooding. The routing of dam reservoirs requires more attention for determining the magnitude of extreme probable flooding. Apparently, the type of structure, importance, and economic development of the surrounding area guide the routing criteria for choosing the extreme flood magnitude. The Maithan and Panchet Dams in India have faced several major floods with diversified magnitudes since 1978. The present study aims to estimate the storage and routing of extreme probable floodings for these two dams based on real-time flood data like inflow, outflow, and elevation for the extreme flood years of 1978, 2009, and 2014. Reservoir storages at different elevations are calculated from the initial storage volumes. For both reservoirs, discharge equations are derived and calculated at given elevations during extreme floods. The Modified Puls technique is used for routing extreme floods. At the end of each extreme flood in 1978, 2009, and 2014, the variation in outflow discharges at different elevations and flood hydrographs is predicted. Finally, estimated outflow discharges are compared with the actual outflow discharges for the given inflows during extreme floods. Using this approach, extreme floods that occurred in 1978 are predicted with less than 10% error. Outcomes from this study may help in the future planning and routing of flood-control detention facilities and in predicting the variation in outflow discharges at different elevations. Based on this work, alternative studies and regional drainage planning can also be carried out. [ABSTRACT FROM AUTHOR]

The introduction of new water supply techniques in the Deccan region of India helped make water a crucial factor in local warfare. Improved water supply and conservation influenced military networks, especially at sites located on the strategic frontiers between local polities. Water management also served residential complexes within fortified sites and agricultural improvements in the surrounding arid landscape. This survey of the Naldurg Fort, overlooking a lofty gorge on the Bhima River in the modern state of Maharashtra, examines how builders in the sixteenth and seventeenth centuries dammed available water to service a strategic frontier military garrison, thereby creating a refreshing environment for a pleasure palace and garden. All photographs and the survey are by Nicolas Morelle. [ABSTRACT FROM AUTHOR]

Urbanization, industrialization and human population explosion not only increased the global power demand, but also led to global warming, pollution and climate change. This encouraged production of power from renewable sources, and thus, hydropower development has been focused. Today, there is more than 1300 GW of installed hydropower across the world, and most of the hydroelectric projects (HEPs) are multi-purpose which includes irrigation, flood and drought mitigation and tourism. Although credited as cheap, clean and green, recent studies demonstrate that the reservoirs of HEPs produce enormous quantities of greenhouse gases (GHGs), including carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O). A large number of estimates on the amount of GHGs from HEPs are available from across the globe. India is next only to USA and China in terms of number of large dams, and thousands of new dams are being planned or constructed, especially in the northeastern part. However, none of these projects have been analyzed in terms of production of GHGs, which is an essential prerequisite for developing such projects and to determine whether carbon emission reduction credits can be accorded or not. The present study was conducted to determine greenness of some of the HEPs of Northeast India in terms of emission of GHGs, and eligibility of the projects for carbon emission reduction credits. Further, the emission of different GHGs through various processes from the Tipaimukh HEP (Manipur) was estimated. In view of the findings, we have provided recommendations, which may be helpful in decision-making process. [ABSTRACT FROM AUTHOR]

India has built over 5000 large dams till date to boost electric power and to enhance irrigated agriculture. In spite of this big dam building venture, India lacks expertise in decommissioning old dams. As a matter of fact, India has more than 500 large dams that were built 50 years ago, and 100 of them have passed over a century. This article analyses the existing facts on India's outdated dams, their safety matters and recommends future strategies to safeguard the large dams from potential future threats. [ABSTRACT FROM AUTHOR]

Applying Charles Tilly's notion of ‘repertoires of contention’, this paper discusses strategies and modes of protest carried out by the movements against hydropower projects in India. It compares the Narmada Bachao Andolan (NBA; Save Narmada Movement) in Madhya Pradesh and the Shramik Mukthi Dal (SMD; Labour Liberation Party) led mobilisations against hydropower projects in Maharashtra. It explains the more dramatic repertoires deployed by NBA as opposed to moderate and pragmatic movement repertoires of SMD. The paper concludes that the differences in ideology, organisation and cultural–historical legacy of the two organisations, as well as their different modes of interaction with the state, are the causes behind different contentious repertoires deployed by them, which resulted in different trajectories and outcomes. [ABSTRACT FROM PUBLISHER]

In the first multipurpose river valley planning of India, the vast resources of Damodar River Basin (DRB) (eastern India) are not only to be envisioned in their entirety but also to be developed in a unified manner where the water, land, and people are simultaneously bounded in a seamless web. Four large dams (Konar, Tilaiya, Maithon, and Panchet), Durgapur barrage, and Tenughat reservoir are built to tamp the flood-prone Damodar River using water resource in an integrated method. The functionality of Damodar fluvial system is controlled by dams, barrage, weirs, sluices, embankments, and canals, maintaining a dynamic equilibrium between fluvial processes and anthropogenic processes. Carrying more than 50 years of legacy, the existing drainage and flood control system of Damodar Valley Corporation has aggravated a number of hydrogeomorphic problems especially in lower DRB, viz. siltation of river bed and reservoirs, uncontrolled monsoonal stream flow, declining carrying capacity of lower course, drainage congestion, low-magnitude annual floods, channel shifting, de-functioned canals, decay of paleochannels, decline of ground water level, and less replenishing of soils with fresh silts. The present paper is mainly tried to investigate the pre-dam and post-dam hydrogeomorphic variability in relation to flood risk and drawbacks of Damodar Valley Multipurpose Project. Specifically, the annual peak flow of Damodar shifts from August to September due to dam construction and reservoir storage. Applying the annual flood series of log Pearson type III distribution, we have estimated post-dam 5-year peak discharge of above 5,300 m s and 100-year flood of above 11,000 m s. Due to siltation, the bankfull discharges of sample segments are gradually declined up to 4,011 m s, 2,366 m s, and 1,542 m s, respectively, having recurrence interval of 1.18-3.18 years only. With the regulation of monsoon flow, the standard sinuosity index is gradually increased downstream, having high dominance of hydraulic factors in respect of topographic factors. The upstream section of study area (Rhondia to Paikpara) now shows the dominance of aggradational landforms, braiding, avulsion, high width-depth ratio, breaching of right bank, and valley widening, but downstream of Barsul the phenomena of bank erosion, confined sinuosity, low width-depth ratio, and narrowness are more pronounced. [ABSTRACT FROM AUTHOR]

Karstic rocks (soluble rocks) exist in different areas of the world having useful/harmful structural and environmental impacts. One of the useful aspect is availability of rich water resources in some regions. An important defect of this kind of rocks is their low strength against water flows. These rocks usually dissolve in acidic water and as a result abundant caverns are created inside them. The gypsum and salt present in these rocks dissolve even in non-acidic water. Presence of these rocks in different foundations and reservoirs especially in dams could be potentially dangerous and cause enormous problems. If dams are located above soluble rocks like limestone, dolomite or gypsum they are endangered by karstification. Karstification is a dynamic process resulting in voids within the rocks due to dissolution. This dissolution leads to the formation of a pipe system within the sub-surface In the physical modeling, effects of cut-off wall height within gypsum layer were examined and monitored. Then with GeoStudio and Flac software, results of physical modeling are analyzed. In each experiment, cut-off wall height was changed. The result of the experiments indicated that as the gypsum Karst is very weak against water, cut-off wall must continue completely within the gypsum layer, as a complete positive cut-off wall. [ABSTRACT FROM AUTHOR]

Hydro-power projects are generally categorized in two segments-- small and large. The 2,000 MW project is being developed by NHPC in Garukamukh, at a cost of approximately $2 billion and height of the dam is 116 metre. But North-east India has a complicated geology and the lower Subansiri is situated in the seismic zone 'V'. So large dam is not suitable for this region as they may fail during an earthquake. River Subansiri has been created tremendous devastation in the riparian villages by its natural flood. So small hydro-power projects are preferable than big projects. All the projects will have downstream impacts. So, NHPC or sensible state should reconsider their plans before it is too late. [ABSTRACT FROM AUTHOR]

Environmental ethics has often been caught between two diverse views namely anthropocentrism and non-anthropocentrism. Attempts were made to reconcile these different viewpoints. One such attempt is from environmental pragmatism, particularly convergent hypothesis, which tries to show that though theoretically anthropocentrism and ecocentrism are different, but practically they complement each other by agreeing on environmental issues. Norton in his work "Towards Unity among environmentalists" (Norton B. G., 1991) talks about a hypothesis, called 'convergent hypothesis', where he mentions that though the anthropocentrists and non-anthropocentrists differ in their ideologies, as far as framing of policies are concerned, they will come up with the same position. He argues that despite divergences regarding ultimate values and justifications, "a consensus on the broad outlines of an intelligent policy" is possible among "environmentalists of different stripes" (Norton B. G., 1991, p. 187). He also says that this hypothesis is the article of environmentalists' faith and it can be falsified by subjecting to experimental text. In this paper we take a case study in India where a big dam for electricity is being built on a tributary river. The present case is an ongoing tussle between the government and a set of people/ organizations over constructing a dam. We try to see the effectiveness of this convergence hypothesis in Indian situation with reference to this particular issue of Subansiri dam construction. [ABSTRACT FROM AUTHOR]

Abstract: Changes in river discharge alter material load and the consequent estuarine and coastal biogeochemical process. Evidence for biogeochemical response to variable rainfall over catchment area or changes in river discharges due to dam regulations is sparse. Inter-annual variability in monsoon rainfall and the consequent river discharges, either dam regulated or otherwise, in India are the best suited to test the influence of altered discharges on estuarine biogeochemistry. Our experiments in Godavari river estuary over three years revealed that a decrease in precipitation over the Indian subcontinent from 2007 to 2009 resulted in the lowering of mean annual discharge from 748.63m3 s-1 in 2007 to 218.40m3 s-1 in 2009. The reduced water discharge, during the peak discharge period, slowed the flushing of the estuary from 1.2days to 6.3days, respectively. The consequent increase in stability of water column and reduced suspended material load gave rise to intense phytoplankton blooms (Chl a 18μgl-1 in 2007 to 28μgl-1 in 2009). Resilience towards the unwanted phytoplankton bloom and overall health of the Indian estuaries is thus tuned by the variability in monsoon rainfall and dam regulated discharge. [Copyright &y& Elsevier]

Summary: The informal construction of small dams to capture runoff and artificially recharge ground water is a widespread strategy for dealing with water scarcity. A lack of technical capacity for the formal characterization of these systems, however, is often an impediment to the implementation of effective watershed management practices. Monitoring changes in reservoir storage provides a conceptually simple approach to quantify seepage, but does not account for the losses occurring when seepage is balanced by inflows to the reservoir and the stage remains approximately constant. To overcome this problem we evaluate whether a physically-based volume balance model that explicitly represents watershed processes, including reservoir inflows, can be constrained by a limited set of data readily collected by non-experts, specifically records of reservoir stage, rainfall, and evaporation. To assess the impact of parameter non-uniqueness associated with the calibration of the non-linear model, we perform a Monte Carlo analysis to quantify uncertainty in the total volume of water contributed to the subsurface by the 2007 monsoon for a dam located in the Deccan basalts near the village of Salri in Madhya Pradesh, India. The Monte Carlo analysis demonstrated that subsurface losses from the reservoir could be constrained with the available data, but additional measurements are required to constrain reservoir inflows. Our estimate of seepage from the reservoir (7.0±0.6×104 m3) is 3.5 times greater than the recharge volume estimated by considering reservoir volume changes alone. This result suggests that artificial recharge could be significantly underestimated when reservoir inflows are not explicitly included in models. Our seepage estimate also accounts for about 11% of rainfall occurring upstream of the dam and is comparable in magnitude to natural ground water recharge, thereby indicating that the reservoir plays a significant role in the hydrology of this small watershed. [Copyright &y& Elsevier]

The image of the past is redefined by communities within a particular cultural context. The future of the past does not flow to a fixed end-point; on the contrary it betrays an anxious and continuous negotiation with the present. The past therefore becomes an invention suited to immediate concerns. In a multicultural country such as India the past lends itself to many interpretations: examples discussed in this miniature article are the visionary geography of Garhwal, the reinvention of the Vailankanni myth and the propagation of the Somnath agenda. [ABSTRACT FROM AUTHOR]