Understanding the Morphological Behaviour of River Chenab: A Case Study


Keywords:
River flow pattern Shifting, Tendency Erosion & Sedimentation, Damage of Spurs, Island FormationAbstract
Ongoing research focuses on the morphology of the Chenab River upstream (U/S) of the Panjnad (PJD) Barrage, Pakistan, particularly addressing erosion concerns from Reduced Distance (RD) 50+000 to 30+000 along the Right Marginal Bund (RMB). A meticulous 18 km field survey, employing plane table survey techniques, leveling tools, compasses, and plane table boards, aimed to map the terrain surrounding the Right Guide Bank (RGB), Left Guide Bank (LGB), RMB, and Left Marginal Bund (LMB). The topography, studied from the main weir, revealed islands near bay number 13–50 due to reduced Chenab flow. Examining RD: 30+000 to 50+000, the section displayed braiding, sandbars, and sediment influx during monsoons, impacting canal diversion and morphology. Despite previous interventions, including j head spurs and mole head spurs, erosion persists along the Chenab's right bank. Sutlej-induced flooding damages LMB up to J-Head Spur RD 5+500 LMB, threatening the upper curved segment of RGB. U/S island formation obstructs the Annex weir, hampering PJD's discharge. A permanent island from RD 36+000 to 50+000 divides Chenab streams, posing an infrastructure threat along RMB. Addressing these issues is crucial for sustainable river management and mitigating potential environmental and infrastructural risks.
Downloads
References
Nanson, G.C., & Knighton, A.D. (1996). Anabranching Rivers: Their cause, character and classification. Earth Surface Processes and Landforms, 21, 217-239.
Parker, G. (1976). On the causes and characteristic scales of meandering and braiding in rivers. Journal of Fluid Mechanics, 76, 457–480.
Kleinhans, M.G., & Berg, J.H.V.D. (2010). River channel and bar patterns explained and predicted by an empirical and a physics-based method. Earth Surface Processes and Landforms, 36, 721-738.
Knighton, A.D. (1974). Variation in width discharge relation and some implications of hydraulic geometry. Geo Society America Bulletin, 85, 1069-1076.
Biedenharn, D.S., Watson, C.C., & Thorne, C.R. (2008). Fundaments of fluvial geomorphology. In: Garcia MH (Ed.), Sediment Engineering: Processes, Measurements, Modelling and Practice. ASCE, Virginia, USA, 355-386.
Darby, S. E., Alabyan, A. M., & Van de Wiel, M. J. (2002). Numerical simulation of bank erosion and channel migration in meandering rivers. Water Resources Research, 38(9), 1163-1185.
Khan, N. I., & Islam, A. (2003). Quantification of erosion patterns in the Brahmaputra Jamuna River using geographical information system and remote sensing techniques. Hydrological Processes, 17, 959-966.
Ercan, A., & Younas, B. A. (2009). Prediction of Bank Erosion in a Reach of the Sacramento River and its Mitigation with Groynes. Water Resources Management, 23, 3121-3147.
Ferguson, R. I. (1987). Hydraulic and sedimentary control of channel pattern. In K.S. Richards (Ed.), River Channels: Environment and Process (pp. 129-158). Basil Blackwell.
Julian, P. J., & Torrres, R. (2006). Hydraulic erosion of cohesive river banks. Geomorphology, 76, 193-206.