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The Ganga River is one of the largest river systems in the world that has built extensive alluvial plains in northern India. The stretch of the Lower Ganga River is vulnerable to siltation because of: (a) the naturally low slope in the alluvial stretch; (b) the confluence of several highly sediment‐charged rivers such as the Ghaghra, Gandak, and Kosi; and (c) the reduction in non‐monsoon flows because of upstream abstractions of both surface and groundwater. Additionally, the Farakka barrage has impacted the morphology of the Ganga River significantly, both upstream and downstream of the barrage. Large‐scale siltation in several reaches has reduced the channel capacity, leading to catastrophic floods in this region even at low discharges. This work has utilized historical remote sensing data and UAV surveys to reconstruct channel morphodynamics and compute sediment volumes accumulated in the channel belt along the Lower Ganga River between Buxar and Farakka. The work was carried out by dividing the total length of the river into four continuous stretches: (a) Buxar–Gandhighat (GW1, 160 km); (b) Gandhighat–Hathidah (GW2, 106 km); (c) Hathidah–Azmabad (GW3, 182 km); and (d) Azmabad–Farakka (GW4, 132 km). We document that major 'hotspots' of siltation have developed in several reaches of the Lower Ganga during the last four to five decades. Sediment budgeting using planform maps provides estimates of 'extractable' volumes of sediment in GW1, GW2, GW3, and GW4 as 656 ± 48, 706 ± 52, 876 ± 71, and 200 ± 85 Mm3, respectively. These estimates are considerably lower than those computed from the hydrological approach using observed suspended sediment load data, which assumes uniform sedimentation between two stations. Further, our approach provides reach‐scale hotspots of aggradation and estimates of extractable sediment volumes, and this can be very useful for river managers to develop a strategic sediment management plan for the given stretch of the Ganga River. [ABSTRACT FROM AUTHOR]

The present study has been carried out in Gangajalghati Block, Bankura district which is located on the eastern slope of Chotanagpur Plateau. IRS-LISS-III data along with other data sets, e.g. existing toposheets and field observation data have been utilized to extract information on the hydrogeomorphic features which include valley fills (VF), buried pediment moderate, buried pediment shallow and structural hills, lineament density contour and slope map of this area. All the information layers have been integrated through geographical information systems analysis and the groundwater potential zones have been delineated. Weighted overlay modelling technique was used to develop a groundwater potential model with three weighted and scored parameters. Although the area is characterized by hard rock, it has groundwater prospective zones due to fracturing, weathering the presence of VF overlying a planation surface. The area has been categorized into four distinct zones-excellent, good, fair and poor. Excellent groundwater potential zones constitute 10-15 % of the total block area, good groundwater potential zones occupy majority of the block, covering approximately 30-35 % and the fair potential zones occupy about 50-55 % of the total block. Poor potential zones occupy very insignificant portion (less than 1 %). [ABSTRACT FROM AUTHOR]

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]

Geomorphology and drainage characteristics of the Gurpur river basin have been studied using satellite images, topographic maps and geographic information system (GIS) techniques. Geomorphology and morphometric parameters have been used to prioritize the sub-basins (SB-I to -VII) and identify the most deficit/surplus zones of groundwater. The study reveals that 8% (SB-VII) to 85% (SB-II) area of the geomorphic units have poor to moderate groundwater prospect. About 16% (SB-V) to 92% (SB-VII) area were estimated as good to excellent zones for groundwater potential. Bifurcation ratio results show that geomorphic control predominates over structural control in the development of drainage network. Computed values of stream frequency of SB-II, SB-III and SB-VI indicate steep ground slopes, with less permeable rocks, while drainage density indicates that the river basin is moderately permeable. Sub-basin-wise prioritization reveals that SB-II is the most deficit zone, while SB-VII is found to be surplus zone of groundwater potential. [ABSTRACT FROM PUBLISHER]

Hydrogeomorphology and lineament studies have been completed by using satellite data for the Pageru river basin, Cuddapah district, Andhra Pradesh, India through visual interpretation of IRS-1B-LISS II FCC (57J/6, J/7, J/10 and J/11) on a 1:50,000 scale. The area has been visually interpreted to delineate various hydrogeomorphic units and lineaments for the development of groundwater. From these studies, various geomorphic units were classified as favourable, moderately favourable and poor zones of groundwater. The integration of geomorphology and lineament studies reveal that shallow groundwater occurrence is controlled by geomorphological characteristics whereas faults/fractures control the yield of groundwater at intermediate depths. [ABSTRACT FROM AUTHOR]