INTERNATIONAL JOURNAL OF GEOMATICS AND GEOSCIENCES Volume 1, No 4, 2011

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1 Stream dynamics change analysis of River Chambal using Remote Sensing and GIS techniques Suryavanshi Shakti 1, Denis D.M. 2, Kumar Dheeraj 1 and Tirkey Gulshan 1 1 Research Scholar, Department of Water Resources Development and Management, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand, India. 2 Professor, Vaugh School of Agricultural Engineering & Technology, Sam Higginbotom Institute of Agriculture, Technology & Sciences, Allahabad, suryavanshi.shakti@gmail.com ABSTRACT In the present investigation, an effort has been made to study the stream dynamics of the Chambal River using Remote Sensing and Geographical Information System techniques. To determine the changes in flow dynamics, meandering and Entrenchment Ratio (ER) of the Chambal river satellite data of MSS (1972), TM (1990) and ETM+ (2000) has been used. In this study, the bankfull width of the river was obtained by digitizing the MSS, TM and ETM+ satellite imaginaries. The central flow lines of the river in all three years were digitized and compared to find out flow dynamics, meandering and Entrenchment Ratio (ER). The origin of the river was considered from the Rana Pratap Sagar dam. The river dynamics changes at forest land, ravineous land and the places where it joins river Yamuna. The river Chambal has been found to be meander continuously towards the right during past 28 years at a distance of 140 km away from the origin. The maximum and minimum width of the river Chambal was found to be 1698 and m at a distance of 300 and 150 km respectively. The maximum ER was found to be 3.5 at a distance of 350 km away from the origin. The study revealed that RS and GIS techniques are useful to find out the stream dynamics of the river. Keywords: Stream Dynamics, Entrenchment Ratio, Meandering, GIS, Remote Sensing. 1. Introduction Since the dawn of civilization, mankind has faced problems associated with rivers and solved them to the best of their ability. More complicated problems are encountered in modern times as increase in population. More and more rivers are being harnessed for multipurpose use flood control, water supply, power generation, irrigation and navigation for which artificial changes are being made in watercourse. These problems have become complicated because of the fact that rivers and other water courses, in most cases, runs through loose material and the water carries some of these material along with it and changes the course of the river. Since river can hardly be said to have structure, fluvial morphology is therefore the science of the form as produced by the action of flowing water of river. Fluvial morphology is particularly important to the hydraulic engineers because many of their greatest problems arise due to the form of streams, brought about by transportation and depositions of sediments by them. According to 813

2 Davis Conception (Davis, 1997) the primary action in the formation of the earth by moving water is the geographical or geomorphologic cycle, which is cyclic erosion passing through several stages. It starts with nearly flat land surface, which is generally wrapped by the movement of the earth crust. This gives rise to increased erosive and transporting power of water flowing from land, the water beginning to carve the landscape into various forms. Matthes (1944) defined meanders as some letter S channel patterns fashioned in alluvial materials, and made a sharp distinction between normal and abnormal stream meanders; the latters are great loops that normally lead to neck offs and isolation of ox bow lakes. Valley slope, bed load, discharge, bed resistance, and transverse oscillation are regarded as basic factors of river meandering. A stream of any volume may assume a meandering course, alternatively eroding sediments from the outside of a bend and depositing them on the inside (Wikipedia, 2011). "Meandering" and "sinuosity" are synonymous and mean any repetitious pattern of bends, or waveforms. In some schemes, "meandering" applies only to rivers with exaggerated circular loops or secondary meanders. Chambal valley of India is particularly well known for its characteristics deep cutting ravines, which has been spreading over the usable land at an alarming rate. The basin is roughly rectangular in shape, with a maximum length of 560 km in a northeast southwest direction. Chambal River flows for some 320 km in a generally northerly direction before entering a deep gorge in Rajasthan at Chourasigarh, about 96 km upstream of Kota. The deep gorge extends up to Kota and the river then flows for about 226 km in Rajasthan in a north easterly direction, and then forms the boundary between MP and Rajasthan for about 252 km. Thereafter, the river forms the boundary between MP and UP for about 117 km, enters UP near Charak Nagar village and flows for about 40 km before joining river Yamuna. The meander ratio or sinuosity index is a means of quantifying how much a river or stream meanders (how much its course deviates from the shortest possible path. Meandering contributes sediment into the river system, chocking the canal system and depositing sediment load into the reservoir (Wikipedia, 2011). In the past few decades the Chambal valley specially Chambal ravines has become a national problem, posing serious problem to agriculture and irrigation planning of lower Chambal valley and constantly damaging the valuable fertile land. The Remote Sensing data provide excellent information about spatial distribution of land in less time and cost effective manner. The accuracy and reliability of mapping and monitoring meandering has been considerably improved with the ability of satellite data having high resolution. The present investigation has been carried out with Remote Sensing approach to determine the entrenchment ratio and the Sinuosity of river Chambal over a period of 28 years from Rana Pratap Sagar Dam upto the point where it joins river Yamuna near Etawah. 2. Materials and Methods The adopted methodology is depicted in figure

3 2.1 Study Area Figure 1: Methodology flow diagram River Chambal, a principal tributary of river Yamuna, originates in the Vindhya range near Mhow in Indore District of Madhya Pradesh, at an elevation of 354 m, at latitude ' and longitude '. Physiographically the area to the north of river Chambal is characterized by deeply dissected plateau and resulting undulating topography. 2.2 Data Used The satellite data products used for the detailed image processing of the river are: I. Multi Spectrum Scanner (MSS) Georeferenced FCC of Resolution of 80 meters, Band [( µ m) Green ( µ m) Red ( µ m) Near IR], Swath Width of 185 Km, Path156, 158 and row 42, 43, 44 of November II. Thematic Mapper (TM) of Resolution of 30 meters, Band [( µ m)blue ( µ m) Green ( µ m) Red ( µ m) Mid IR], Swath Width of 185 Km, Path145, 146 and 147 and row 42, 43, 44 of November

4 III. Enhanced Thematic Mapper (ETM) of Resolution of 30 meters, Band[( µ m) Red ( µ m) Near IR ( µ m) Mid IR], Swath Width of 185 Km, Path145, 146 and 147 and row 42, 43, 44 of November The Geo referenced satellite data obtained from / GLCF.com was mosaiced for area of interest and banks of river Chambal were digitized and Landsat MSS 1972, TM 1990, ETM2000 data was used to identify the changes between the years 1972, 1990 and ERDAS imagine 8.4 software package were used to carry out processing of satellite data. The outline of the bankfull width of river was digitized on screen, for each satellite imagery separately (Figure 2). These vector files obtained from each satellite imaginaries were then appended into one vector file to find the changes in bankfull width. Figure 2: Overlapped digital central flow lines of the river Chambal for the years 1972, 1990, and 2000 The centerline of the river was digitized in the FCC s. Thereafter a grid of 10 km 10 km was superimposed on the FCC. At the entire junction where the central line of the river cuts the vertical or horizontal grid, accordingly the distance of left hand side and right hand side bank from the central line was measured. The ratio of length of left hand side and that of right hand side is the entrenchment ratio. Sinuosity Index is a term indicating amount of curvature in the channel. The sinuosity is computed by dividing the channel centerline length by the length of valley center line. In other words, sinuosity index is the stream length between two points on a stream divided by the valley length. Sinuosity Index has a non mathematical utility as well. Streams can be placed in 816

5 categories arranged by it; for example, when the index is between 1 to 1.5 the river is sinuous, but if between 1.5 and 4, then meandering. Sinuosity Index as classified by Rosgen (1994) : I Strong when sinuosity index ratio > 1.4; stream has numerous closely spaced bunds, very few straight sections. II Moderate when sinuosity index ratio >1.2<1.4; stream has good sinuosity with some straight sections. III Weak when sinuosity index ratio >1< 1.2; stream has very few bunds, and mostly straight sections. IV Absent when sinuosity index ratio =1; stream is completely straight with no bunds. 3. Results and Discussions 3.1 Bankfull Measurement Landsat MSS (1972), TM (1990), ETM (2000) data of River Chambal were analyzed. The Entrenchment Ratio and Sinuosity Index of downstream Chambal River were obtained to understand the sinuosity of river over a period of 28 years. Entrenchment Ratio was obtained at every 10 km and Sinuosity Index at every 50 Km and also for the full length of the river. 3.2 Entrenchment Ratio Entrenchment Ratio of the river as per MSS (1972) imaginary: The Entrenchment Ratio obtained indicates that the movement of river up to the distance of 200 km is towards LHS bank. Thereafter it meanders towards RHS bank up to 220 km and finally moves on LHS bank up to the distance of 330 km. Again from km, it meanders on RHS bank and from km; it flows nearer to the LHS bank. From km it flows towards LHS bank and beyond 490 km up to 530 km, it flows towards LHS bank and beyond that river tends to move on RHS bank Entrenchment Ratio of the river as per TM (1990) imaginary: The Entrenchment Ratio obtained, indicates that the movement of river up to the distance of 70 km from Rana Pratap Sagar dam is towards RHS bank. Up to a distance of 120 km river moves towards LHS bank. Again from km, the river is moves towards RHS bank. Thereafter the river moves towards the RHS bank from km. Beyond 320 km it is observe that there is a continuous change in the flow dynamics of the river, where the ER is changing significantly at every km. Entrenchment Ratio of the river as per ETM (2000) imaginary: 817

6 The Entrenchment Ratio for the year 2000 using (ETM) data shows that the movement of river up to the distance of 100 km from Rana Pratap Sagar dam is towards RHS bank. Then the river is almost stable in the region of km. There after it is observed that the movement of the river is towards LHS bank from km, where the ER of the river is less than 1. Further on, from km from the Rana Pratap Sagar dam the river is moving towards RHS where the average ER is more than 1 and it is maximum (3.5) at 350 km. From km we observe a regular meandering pattern where the ER is varying on either side of the river. 3.3 Sinuosity Index The Sinuosity Index for the river has been classified into strong, moderate and weak. Downstream RPS Dam as the thalweg is followed from 50 to 150 Km, 400 to 450 Km, 550 to 600 Km for MSS (1972), TM (1990) and ETM (2000), the Sinuosity Index was strong. It was also strong for ETM (2000) at a thalweg length from 500 to 550 Km. Large variations in the Entrenchment Ratio shown in figure 3, clearly indicates that the Meandering is very rapid at these locations. Downstream RPS Dam as the thalweg is followed from 00 to 50 Km, 150 to 200 Km, 450 to 500 Km for MSS (1972), TM (1990) and ETM (2000), the Sinuosity Index was moderate. It was also moderate for MSS (1972) at the thalweg length from300 to 350Km and 500 to 550 Km. for TM (1990) at the thalweg length from 200 to 250 Km, 300 to350km and 500 to 550 Km. And ETM (2000) at a thalweg length from 200 to 300 Km, 350 to 400Km. The marginal variations in the Entrenchment Ratio shown in figure 03, clearly indicates that the Meandering is moderate at these locations. S in u o s ity I n d e x Distance ( Km) E n tra n c h m e n t R a ti o MSS TM ETM ME MSS ME TM ME ETM Figure 3: Downstream RPS Dam as the thalweg is followed from 200 to 300 Km and 350 to 400Km for MSS (1972), 250 to 300Km and 350 to 400 Km for TM (1990) and 300 to 350 Km for ETM (2000), the Sinuosity Index was weak. The very little variations in the Entrenchment Ratio shown in figure 3, clearly indicates that the Meandering is weak at these locations. 818

7 3.4 Sinuosity Index of the River The Sinuosity Index of the river from 1972 to 1990 and 2000 has been obtained and shown in figure 4. From this figure it is seen that the Sinuosity Index of the river is gradually moving from moderate to strong i.e.1.22 in 1972, 1.31 in 1990, 1.31 in Sinuosity Index years (1 1972, , ) 4. Conclusion Figures 4 The maximum continuous movement of the river towards the right hand side from has been observed at 140 km from Rana Pratap Sagar dam and has shifted by 108% from 1972 position. Excessive sedimentation has been observed between km. The maximum width of the river is 1698 meter at 300 km and minimum km at 150 km from the Rana Pratap Sagar dam. The Entrenchment Ratio was found to be maximum of 3.5 at 350 km from Rana Pratap Sagar Dam. These figures are ringing the alarm bell because as the Sinuosity Index increases, it indicates that the meandering activity of the river increases, thus contributing more sediment into the river. Measure should be taken so as to reduce the rise in Sinuosity Index to save precious land from been eroded all along the river course. 5. References 1. Davis Coller, R.J., (1997) Stream Channels are narrower in pasture than forest: New Zealand Journal Of Marine And Freshwater Resources, v.31, p Dunne, T., And Leopold, L.B., 1978, Water in environment planning: San Francisco, W.H. Freeman Douglas (2000), Stream change analysis using remote sensing and geographical information systems., J. Range Manage 54, pp A22 A50 819

8 3. Hickin and Edward J. (2003), "Meandering Channels", in Middleton, Gerard V., Encyclopedia of Sediments and Sedimentary Rocks, Dordrecht, Boston, London: Kluwer Academic Publishers, pp Matthes G H. (1941), Basic aspects of stream meanders, Transactions of American Geophysicst Union, 22, pp Michaud, Joy P. (1991), A Citizens Guide to Understanding and Monitoring Lakes and Streams. Washington State Department of Ecology. Publication # 94,pp NC Division of Water Quality. (2005), Identification Methods for the Origins of Intermittent and Perennial streams, Version 3.1. North Carolina Department of Environment and Natural Resources, Division of Water Quality. Raleigh, NC. 7. Prislo., Lei., Hurd. (2001), Interactive GIS based impervious model, in Proceedings of the ASPRS Annual Convention, April 23 27, St. Louis, Missouri: Bethesda, Maryland, The American Society for Photogrammetry & Remote Sensing, CD ROM. 8. Ripp B. J., P.E., P.G., CPESC; R. D. Prager, P.E.; and E. Ubben (2003), Meander Geometry and Sinuosity Relationships of Urbanized Beal Slough in Lincoln, Nebraska ASCE Conference Proceedings 139, pp River meandering dynamics (2002), Physical Review E: Statistical, Nonlinear, and Soft Matter Physics, 65, (4 2B), / / Rosgen David L. (1994), A classification of natural rivers. Catena 22, Stream Corridor Restoration, Principles, Processes, and Practices. (1998), (revised 08/2001). The Federal Interagency Stream Restoration Working Group. 12. Williams (1986), River meanders and channel size. Journal of hydrology 88: content and notes related to stream, accessed during May,