Greater Himalayan Research Articles

Variability of Diurnal Temperature Range During Winter Over Western Himalaya: Range- and Altitude-Wise Study

The current trends in diurnal temperature range, maximum temperature, minimum temperature, mean temperature, and sun shine hours over different ranges and altitudes of Western Himalaya during winter have been studied. Analysis of 25 years of data shows an increasing trend in diurnal temperature range over all the ranges and altitudes of Western Himalaya during winter, thereby confirming regional warming of the region due to present climate change and global warming. Statistical studies show significant increasing trend in maximum temperature over all the ranges and altitudes of Western Himalaya. Minimum temperature shows significant decreasing trend over Pir Panjal and Shamshawari range and significant increasing trend over higher altitude of Western Himalaya. Similarly, sunshine hours show significant decreasing trend over Karakoram range. There exists strong positive correlation between diurnal temperature range and maximum temperature for all the ranges and altitudes of Western Himalaya. Strong negative correlation exists between diurnal temperature range and minimum temperature over Shamshawari and Great Himalaya range and lower altitude of Western Himalaya. Sunshine hours show strong positive correlation with diurnal temperature range over Pir Panjal and Great Himalaya range and lower and higher altitudes.

Modern pollen deposition in glacial settings in the Himalaya (India): abundance of Pinus pollen and its significance

ABSTRACTThirty-five surface sediment samples from three glacial sites – [Chorabari Glacier (Kedarnath), Hamtah and Chhatru glaciers (Lahaul-Spiti)] – situated in the western Himalaya, India, were palynologically analysed to explore the relationship between the modern pollen assemblages and the extant vegetation. The Chorabari Glacier is located in the Greater Himalaya and influenced by the Southwest Summer Monsoon; whereas the Hamtah and Chhatru glaciers are located in the Trans-Himalaya and affected more by the Western Disturbances (winter precipitation). The area around Chorabari Glacier receives abundant rainfall, while the Hamtah and Chhatru glaciers are in a high-altitude cold desert. Palynological studies have revealed an overwhelming dominance of Pinus pollen in all the samples. Though the sampling sites are 2 to 8 km away from the treeline and characterised by herbaceous ground vegetation, the marked predominance of arboreal pollen (especially Pinus) in the sediments stresses the importance of a proper interpretation of modern pollen data, so as to have an appropriate standard for deciphering the pollen–vegetation relationship in the respective study areas.

Petrotectonic setting of the provenance of Lower Siwalik sandstones of the Himalayan foreland basin, southeastern Kumaun Himalaya, India

AbstractDetailed petrography and modal analysis of 35 sandstone thin sections was carried out to determine petrotectonic setting of the provenance of the Lower Siwalik molasse of southeastern Kumaun Himalaya. The sandstones are fine‐ to coarse‐grained (0.14–0.63 mm), poorly‐ to moderately‐sorted and comprise lithic arenites, sublithic arenites and lithic greywackes. The sandstones invariably belong to the quartzolithic QtFL (Qt, total quartz; F, feldspar; L, lithic grains) and QmFLt (Qm, monocrystalline quartz; Lt, lithic grains plus polycrystalline quartz) petrofacies, and indicate their derivation from a quartzose‐ and transitional‐recycled orogen provenance under sub‐humid climatic conditions. The framework composition of the sandstones comprises abundant monocrystalline and polycrystalline quartz and low‐ to high‐grade metamorphic rock fragments, along with subordinate feldspar, characterized by low ratios of plagioclase to total feldspar, and accessory minerals. The framework composition and petrofacies characters of these texturally submature sandstones suggest their derivation mainly from the nearby located Great Himalaya terrane and subordinately from the Tethys and Lesser Himalayan terranes. A comparison of the data presented here with the previous similar data from Lower Siwalik of northwestern Pakistan, northwestern India, south‐central Kumaun, western Nepal and southeastern Nepal reveals that like the Lower Siwalik rivers in other sections, the Lower Siwalik rivers of the southeastern Kumaun too drained large parts of the Great Himalayan terrane and some parts of the Tethys and Lesser Himalayan terranes.

Methanolic Extracts of the Rhizome of <i>R. emodi</i> Act as Bioenhancer of Antibiotics against Bacteria and Fungi and Antioxidant Potential

Rheum emodi (Himalayan rhubarb) is used as a medicinal herb in the greater Himalayas. The present study investigated the antimicrobial and antioxidant properties of methanolic extracts of rhizome of R. emodi . The methanolic extract showed the presence of phenolics, tannins, flavonoids, carbohydrates, glycosides and phytosteroids. Methanolic extract showed higher total phenolic content (258±6.87 mg/gm GAE) as compared to flavonoid content (50±2.6 mg/gm RE) and inhibited the growth of Gram positive ( Bacillus subtilis , Staphylococcus aureus ), and Gram negative ( Escherichia coli , Klebsiella pneumonia ) bacteria. Minimum inhibitory concentration was comparatively less for Gram-negative (0.2-0.39 µg/ml) as compared to Gram-positive bacteria (0.78-1.56 µg/ml). When tested against yeast, R. emodi extract also showed comparatively more growth inhibition to Candida albicans (MTCC277) and C. albicans (ATCC90028) as compared to Saccharomyces cerevisiae (H1086). DPPH radical scavenging and FRAP assays of the methanolic extracts of R. emodi (IC 50 value 60.89 μg/ml with DPPH assay and 13.022 µM Fe (II) equivalents) were comparable to ascorbic acid (IC 50 value 43.84 μg/ml with DPPH assay and 2.682 µM Fe (II) equivalents). Methanolic extract of R. emodi showed synergistic antifungal activity when combined with fluconazole ( S. cerevisiae and C. albicans ) and amphotericin B ( S. cerevisiae ) and converting the extract from fungistatic to fungicidal. Combination of erythromycin and tetracycline with R. emodi extract showed synergistic antibacterial activity against E. coli and K . pneumonia and a combination of R. emodi extract with tetracycline demonstrated antibacterial activity against K . pneumonia . Moreover, extract alone showed fungistatic activity but specific fungicidal activity when combined with amphotericin B or fluconazole.

Climate change and its threats to sustainable agriculture

Global warming, climate change and environmental degradation constitute the biggest threat to human civilization. Temperature measurement records on land and sea, shrinking polar ice sheets, recession in mountain glaciers, rise in sea level and ocean acidifi cation are manifestation of global temperature increase, estimated at 0.8–1.0°C since 1880. The present day global warming is generally considered a consequence of the accumulation in atmosphere of greenhouse gases, notably CO 2 , which result from burning of hydrocarbons in industry, power generation, vehicles and domestic use. Global warming would result in melting of glaciers and polar icecaps, unpredictable weather patterns, natural disasters (e.g., fl oods), disruption of existing communication systems and infrastructure, health issues, sea level rise and unmanageable threat to coastal regions. It can trigger the vicious circle of food insecurity, human migration and confl icts. Climate change can cause unpredictable changes in weather patterns, erosion of soil, desertifi cation of cultivable land, disruption of existing irrigation systems, and reduction of tropical forest cover. Hence, it would have severe impact on agriculture sector, food security and its supply chain. Melting of the glaciers in Tibet and greater Himalaya would adversely affect the food security and life pattern of three billion people. To mitigate climate change and harness food security, diverse sustainable and environment friendly techniques, such as crop rotation, integrated pest management, hydroponics, cultivation of salt tolerant plants, and effi cient irrigation techniques need to be employed. But, most importantly, the impending disaster of global warming can only be avoided by urgently controlling the emission of greenhouse gases.

Disentangling the mechanisms behind winter snow impact on vegetation activity in northern ecosystems.

Although seasonal snow is recognized as an important component in the global climate system, the ability of snow to affect plant production remains an important unknown for assessing climate change impacts on vegetation dynamics at high-latitude ecosystems. Here, we compile data on satellite observation of vegetation greenness and spring onset date, satellite-based soil moisture, passive microwave snow water equivalent (SWE) and climate data to show that winter SWE can significantly influence vegetation greenness during the early growing season (the period between spring onset date and peak photosynthesis timing) over nearly one-fifth of the land surface in the region north of 30 degrees, but the magnitude and sign of correlation exhibits large spatial heterogeneity. We then apply an assembled path model to disentangle the two main processes (via changing early growing-season soil moisture, and via changing the growth period) in controlling the impact of winter SWE on vegetation greenness, and suggest that the "moisture" and "growth period" effect, to a larger extent, result in positive and negative snow-productivity associations, respectively. The magnitude and sign of snow-productivity association is then dependent upon the relative dominance of these two processes, with the "moisture" effect and positive association predominating in Central, western North America and Greater Himalaya, and the "growth period" effect and negative association in Central Europe. We also indicate that current state-of-the-art models in general reproduce satellite-based snow-productivity relationship in the region north of 30 degrees, and do a relatively better job of capturing the "moisture" effect than the "growth period" effect. Our results therefore work towards an improved understanding of winter snow impact on vegetation greenness in northern ecosystems, and provide a mechanistic basis for more realistic terrestrial carbon cycle models that consider the impacts of winter snow processes.

Frequency‐Dependent Coda Amplitude Decays in the Region of Himalaya, India

Abstract An earthquake dataset consisting of 327 records from 67 earthquakes is used to study the frequency‐dependent amplitude decay of seismic coda waves in the Kumaon Himalayas, India. Coda amplitude decays with time t are measured by empirical t − α dependences, with exponent α being variable regionally with frequencies and lapse times. The results show that α varies from 1 to 3, with an average of about 1.93. The lapse‐time dependence of α is noticeable but weak, and no significant azimuthal dependence of α is obtained. Significant regional variations of α are found, ranging from α ≈2.1 for the Lesser Himalaya to α ≈1.76 for the Greater Himalaya. These variations correlate with the geology of the region and crustal structure. The values of α are mostly frequency independent, indicating low intrinsic attenuation within the crust. When interpreted according to the conventional coda‐ Q ( Q c ) model, these values of α lead to Q c ≈78 f 1.06 in the Kumaon Himalaya, Q c ≈90 f 1.09 in the Kumaon Lesser Himalaya, and Q c ≈90 f 0.92 in the Kumaon Greater Himalaya. A frequency‐dependent α is found within a localized area, giving an estimate of near‐surface Q ≈200. Three general conclusions of this study may be significant for coda studies in other areas. First, the values of α are variable regionally, whereas its average level is remarkably constant and correlates with rock types and upper‐crustal structure. Second, the traditionally assumed value of α =1 is much lower than the actual spreading rates, which shows that the coda cannot be viewed as body waves scattered within a uniform crust. Using the value of α =1 causes a systematic underestimation of coda amplitude decays in the data. Third, the dependence of α on frequency is relatively weak and occurs in localized areas. Combined with an underestimated α , this weak frequency dependence may cause biases in the estimation of secondary parameters, such as coda Q .

Abrasion-set limits on Himalayan gravel flux

Rivers sourced in the Himalayan mountain range carry some of the largest sediment loads on the planet, yet coarse gravel in these rivers vanishes within approximately 10-40 kilometres on entering the Ganga Plain (the part of the North Indian River Plain containing the Ganges River). Understanding the fate of gravel is important for forecasting the response of rivers to large influxes of sediment triggered by earthquakes or storms. Rapid increase in gravel flux and subsequent channel bed aggradation (that is, sediment deposition by a river) following the 1999 Chi-Chi and 2008 Wenchuan earthquakes reduced channel capacity and increased flood inundation. Here we present an analysis of fan geometry, sediment grain size and lithology in the Ganga Basin. We find that the gravel fluxes from rivers draining the central Himalayan mountains, with upstream catchment areas ranging from about 350 to 50,000 square kilometres, are comparable. Our results show that abrasion of gravel during fluvial transport can explain this observation; most of the gravel sourced more than 100 kilometres upstream is converted into sand by the time it reaches the Ganga Plain. These findings indicate that earthquake-induced sediment pulses sourced from the Greater Himalayas, such as that following the 2015 Gorkha earthquake, are unlikely to drive increased gravel aggradation at the mountain front. Instead, we suggest that the sediment influx should result in an elevated sand flux, leading to distinct patterns of aggradation and flood risk in the densely populated, low-relief Ganga Plain.

The nature and evolution of the Main Central Thrust: Structural and geochronological constraints from the Sikkim Himalaya, NE India

The Main Central Thrust (MCT) is a prominent continental-scale fault within the Himalaya. Its definition has been the topic of some debate in the literature. After a brief consideration of the state of discussion to clarify the definition we use in this work, we report features from the field- to the microstructural- scale of a particularly well-exposed section in Sikkim, NE India. The nature of the protoliths as well as the overlying and underlying rocks is characterized in terms of ε-Nd. The dates of motion on the fault are constrained using U–Pb geochronology of zircon and monazite from pegmatitic dikes that cross-cut the deformation fabric. It is found that the mechanism of deformation recorded in the fault zone rocks is different compared to that found in the overlying Greater Himalayan (GH) or the underlying Lesser Himalayan (LH) rocks. The GH and LH have different protolith characteristics as well. Combined with existing data on P–T history, dates of metamorphism, and cooling- and exhumation-rates of the GH and the LH, our measurements show that major motion on this fault occurred before 20Ma at 450–700°C but after peak metamorphism of rocks (750–800°C) in this zone. Isolated events occurred in this zone as late as 11Ma, possibly in the brittle domain. This underscores the pulsed nature of movement over an extended period on such major faults, and the related difficulties in dating fault movement, determination of the rates of movement, and designating a fault plane as in- or out-of-sequence within a propagating deformation front.

Diversity and Status of Butterfly Fauna in Greater Himalayan Belt of Himachal Pradesh

The Greater Himalayan range (5000–6000 meters) runs along the eastern boundary and is cut across by the Sutlej. This belt is very cold climate zones, having very steep hilly terrains with some forested patches of chilgoja pine, willow etc.. Keeping in view the intensive and extensive bioecological studies in the various physiographic conditions of this belt, various natural ecosystems/habitats like forests, grasslands and pastures, rivers, lakes and wetlands, human habitations etc., spread over different biogeographically zones were selected for the present studies. This belt was selected on the basis of certain logistics like time frame, resources and size of the area etc., so as to get the maximum data regarding butterflies diversity. These investigations mainly aimed at knowing the current status of butterflies in different habitats of this zone. In order to study the diversity and status in Greater Himalayan belt of Himachal Pradesh was explored for the presence of butterfly fauna in various ecosystems/habitats types, during different seasons of the years revealed the presence of 17 species of insects belonging to 15 genera and 6 families. During the course of present studies it was observed that Nymphalidae, represented by 6 species was the largest family followed by Satyridae & Pieridae 4 species each and Papilionidae, Danaidae & Acraeidae were represented by only one species each. Analysis of seasonal variation in the diversity of butterflies in different habitat of the areas revealed that maximum diversity has been recorded during pre and post monsoon periods. On the contrary, minimum diversity was seen during winter months of December and January respectively. The goal of systematic is to understand species, what they are and how they are related to reflect such relationships in a formal classification and to provide distinctive names for the group recognized.

Atmospheric aerosol radiative forcing over a semi-continental location Tripura in North-East India: Model results and ground observations.

Northeast India (NEI) is located within the boundary of the great Himalayas in the north and the Bay of Bengal (BoB) in the southwest, experiences the mixed influence of the westerly dust advection from the Indian desert, anthropogenic aerosols from the highly polluted Indo-Gangetic Plains (IGP) and marine aerosols from BoB. The present study deals with the estimation and characterization of aerosol radiative forcing over a semi-continental site Tripura, which is a strategic location in the western part of NEI having close proximity to the outflow of the IGP. Continuous long term measurements of aerosol black carbon (BC) mass concentrations and columnar aerosol optical depth (AOD) are used for the estimation of aerosol radiative forcing in each monthly time scale. The study revealed that the surface forcing due to aerosols was higher during both winter and pre-monsoon seasons, having comparable values of 32W/m2 and 33.45W/m2 respectively. The atmospheric forcing was also higher during these months due to increased columnar aerosol loadings (higher AOD ~0.71) shared by abundant BC concentrations (SSA ~0.7); while atmospheric forcing decreased in monsoon due to reduced magnitude of BC (SSA ~0.94 in July) as well as columnar AOD. The top of the atmosphere (TOA) forcing is positive in pre-monsoon and monsoon months with the highest positive value of 3.78W/m2 in June 2012. The results are discussed in light of seasonal source impact and transport pathways from adjacent regions.

Climate change over Leh (Ladakh), India

Mountains over the world are considered as the indicators of climate change. The Himalayas are comprised of five ranges, viz., Pir Panjal, Great Himalayas, Zanskar, Ladhak, and Karakorum. The Ladakh region lies in the northernmost state of India, Jammu and Kashmir, in the Ladhak range. It has a unique cold-arid climate and lies immediately south of the Karakorum range. With scarce water resources, such regions show high sensitivity and vulnerability to the change in climate and need urgent attention. The objective of this study is to understand the climate of the Ladakh region and to characterize its changing climate. Using different temperature and precipitation datasets over Leh and surrounding regions, we statistically analyze the current trends of climatic patterns over the region. The study shows that the climate over Leh shows a warming trend with reduced precipitation in the current decade. The reduced average seasonal precipitation might also be associated with some indications of reducing number of days with higher precipitation amounts over the region.

High‐resolution seismic tomography of the 2015 Mw7.8 Gorkha earthquake, Nepal: Evidence for the crustal tearing of the Himalayan rift

AbstractThe Mw7.8 Gorkha earthquake struck Nepal and ruptured the boundary between the Indian and Eurasian plates. We conducted 2‐D Pg wave tomography to clarify the seismogenic structure and try to understand causal mechanisms for this large earthquake, using the aftershock data recorded by 15 broadband seismic stations located near the China‐Nepal border. Our high‐resolution results show that coseismic slip area of the main shock is consistent with the high P wave velocity anomaly, and the region of maximum slip has a larger area with higher velocity than the region of initial slip, possibly resulting in the dominant low‐frequency radiation of energy observed after the dominant high‐frequency radiation of energy in the source rupture process. The boundary between these regions of contrasting high and low seismic velocity anomalies suggests a potential crustal tearing at the southern end of the Tangra Yum Co Rift, possibly resulting from different thrust speeds in the Greater Himalaya.

Interpretation of Gravity Data using 3D Euler Deconvolution, Tilt Angle, Horizontal Tilt Angle and Source Edge Approximation of the North-West Himalaya

The collision of the Indian plate and the Eurasian plate created shortening and imbrications with thrusting and faulting which influences northward tectonic movement. This plate movement has divided the Himalaya into four parts, viz. Outer Himalaya, Lesser Himalaya, Greater Himalaya, and Tethys Himalaya. The crystalline basement rock plays an imperative role for structural and tectonic association. The study has been carried out near Rishikesh-Badrinath neighborhood in the northwestern part of the Himalayan girdle with multifarious tectonic set up with thrusted and faulted geological setting. In this study area, 3D Euler deconvolution, horizontal gradient analysis, tilt angle (TILT) and horizontal tilt angle (TDX) analysis have been carried out using gravity data to delineate the subsurface geology and heterogeneity in the northwestern part of Himalaya. The Euler depth solutions suggest the source depth of about 12 km and various derivative analyses suggest the trend of the delineation thrust-fault boundaries along with the dip and strike direction in the study area.

Observed spatio‐temporal changes of winter snow albedo over the north‐west Himalaya

ABSTRACTThis study presents the spatio‐temporal winter snow albedo analysis over different mountain ranges of north‐west Himalaya (NWH) for a period of approximately 24 years. Here we assess the temporal albedo variations in past two decades (1991–2010) in comparison to the recent 14 years (2000–2014). The field collected manual data of two representative observatories of Lower Himalaya (LH) and Great Himalaya (GH), and six automatic weather stations in LH, GH and Karakoram Himalaya (KH) were analysed. Satellite derived MODIS albedo data (MOD10A1) over these stations between 2001 and 2014 were analysed. A good correlation (r = 0.59) was observed between monthly average MODIS retrieved albedo and field collected albedo for GH with a relative error of 11%. In past two decades, a statistically significant (99%) decreasing rate of −0.011 per year in winter snow albedo was observed over GH (1993–2010), while in recent decade (2001 onward), no statistically significant increasing trend was observed. The change in albedo of GH is attributed to winter mean air temperature, which shows a significant rise in the past two decades, but there has been a hiatus in winter mean air temperature rise in recent decade. The higher winter mean air temperature above 0 °C since beginning of the study period (1991 onward) kept albedo of moist/wet snow approximately stable in LH. Further, insignificant increasing trend of albedo was observed over KH range in recent decade, and it is attributed to persistent very low temperatures and an increase in the frequency of snowfall days. This albedo study over NWH supports the recently reported findings on Himalayan snow cover and glacier variations during different durations.

Pressure–temperature–structural distance relationships within Greater Himalayan rocks in eastern Bhutan: implications for emplacement models

AbstractIn the Himalayan orogen, Greater Himalayan (GH) rocks were buried to mid‐ to lower‐crustal levels and are now exposed across the strike of the orogen. Within the eastern Himalaya, in the Kingdom of Bhutan, the GH is divided into structurally lower (lower‐GH) and upper (upper‐GH) levels by the Kakhtang thrust (KT). Pressure–temperature estimates from lower‐ and upper‐GH rocks collected on two transects across the KT yield similar P–T–structural distance trends across each transect. In the eastern transect, temperatures are similar (from 730 to 650 °C) over a structural thickness of ~11 km, but peak pressures decrease from ~10 to 6 kbar with increasing structural level. In comparison, peak temperatures in the central Bhutan transect are similar (from 730 to 600 °C), but pressures decrease from 10 to 6.5 kbar with increasing structural level over a structural thickness of ~6 km. The structurally highest sample reveals slightly higher pressures of 8.0 kbar in comparison to pressures of ~6.5 kbar for samples collected from within the KT zone, ~4 km below. Within each transect, there are increases in pressure ± temperature within the overall upright P–T gradient that may demarcate intra‐GH shear zone(s). These P–T results combined with evidence that the timing of initial melt crystallization becomes older with increasing structural level suggest that the intra‐GH shear zones emplaced deeper GH rocks via progressive ductile underplating. These shear zones, including the KT, likely aided in the initial emplacement and construction of the GH as a composite tectonic unit during the Late Oligocene to Early Miocene, from c. 27 to 16 Ma.

Psora altotibetica (Psoraceae, Lecanorales), a new lichen species from the Tibetan part of the Himalayas

In the present study, we describe the new species, Psora altotibetica, from nine localities in China (Tibetan area) and Nepal. The study includes analyses of anatomy, secondary chemistry, and DNA sequence data of P. altotibetica and presumed close relatives. Psora altotibetica resembles P. indigirkae morphologically, but is phylogenetically closer to P. tenuifolia and P. vallesiaca. It differs from P. indigirkae in the colour of the apothecia, the size of the ascospores, and in the secondary chemistry. The species is terricolous and was collected in the alpine zone of the Great Himalayas between 4230 and 5000 m altitude. Psora tenuifolia and P. vallesiaca are here reported as new to China and the Himalayas.

Monitoring of glacier in Alaknanda basin using remote sensing data

Summary This study monitors the great Himalayas between the year 1998–2008 using satellite data. The Landsat satellite data was used to monitor variations in the area of glacier. Further the snow-covered area (SCA) of the part of Alaknanda basin was computed both for the winter and the summer season. The analysis for the same was done between 1998 and 2008. It was observed that the amount of decrease in the SCA was more in winter season compared to summer season, which also shows the rate of retreat of glacier. This study also classifies the snow into two categories (1) dry snow and (2) wet snow. The pattern in the change in area of these two categories was analysed both for the winter and summer season.

Flora of Niti Valley: a cold arid region of Nanda Devi Biosphere Reserve, Western Himalaya, India

Located in the extended buffer zone of Nanda Devi Biosphere Reserve in Western Himalaya, Niti valley represents a cold arid region. The reserve has been extensively surveyed in terms of floral diversity by various workers, albeit highly confined to the core zones. The current survey recorded 495 species belonging to 267 genera and 73 families of vascular plants through systematic collection in the years 2011, 2012 and 2014. Of the recorded species, 383 were dicots, 93 monocots, 9 pteridophytes and 10 gymnosperms. Asteraceae was most diverse family (32 genera with 58 species), followed by Poaceae (22 genera with 41 species), Lamiaceae (15 genera with 19 species) Fabaceae (14 genera with 22 species), Brassicaceae (12 genera with 12 species) and Rosaceae (11 genera with 36 species). The present survey also updates the existing flora of Nanda Devi Biosphere Reserve (801 species) with addition of 167 species. This study reveals that the Niti valley forms a transition zone, as the floral elements have affinity with Trans as well as Greater Himalaya.

Evaluation of Rubber Dams for SHP in India

India is blessed with great Himalayas as well as hilly areas in peninsular and central areas providing opportunity for hydro power at all scale including Small Hydropower (SHP) development. Water is diverted from the streams for hydro power generation using suitable diversion structures. Conventional types of raised-crest weirs are not well suited for hill streams having steep slopes and boulder movement during floods. Inflatable dam or also known as rubber dam is one type of diversion structure to control and regulate the water for power generation.The experience of inflatable dams in India is very limited even though worldwide over 4,000 installations exist and more than 10 manufacturers offer this type of weir. There are only three installations so far used for irrigation or municipal purposes and not a single rubber dam for hydropower projects in India. For selecting a suitable diversion structure, economic and technical aspects are to be carefully considered. Different types of diversion weirs including rubber dam used for diverting water for Small Hydropower (SHP) projects are studied and presented. The design of diversion weir depends on the quantity of water withdrawal and width of stream. This study is an attempt to study the rubber dam technology for Small Hydropower in India. Five different sites were selected for the present study. Rubber dam was also compared with conventional raised gravity weir, trench weir (Tyrolean), bush and boulder weir and “mathu bund” (a local name). The life cycle of these different types of weirs for same hydraulic conditions and for different discharge were computed and compared with that of imported rubber dam as well as Indian rubber dam. The cost of rubber dam was estimated based on personal communications with the experts of manufacturers and practitioners of the subject area, as well as case studies of already constructed rubber dams in India installed for purposes other than hydropower. Operation and maintenance cost and different losses on account of head, water loss and repair were taken into account for different types of weirs for calculating life cycle cost. Possible damage that may be caused by major flood for different types of weir was also calculated monetarily in terms of power loss. The ease of inflation and deflation reduces the flood damage cost, O & M cost, sediment removal cost and repair work cost. With the comparative analysis, it is found that average life cycle cost of raised gravity weir, bush and boulder, mathu bund and trench weir (Tyrolean), is 2,3, 5 and 6 times respectively more than imported rubber dam. Life cycle cost of Indian rubber dam and average life cycle cost of imported rubber dam is about three times more than Indian rubber dam. It is recommended to use inflated weir in Small Hydropower projects being cost effective and energy efficient.