KOSHI RIVER BASIN CHALLENGES IN. Koshi Basin. Koshi: A Sorrow of Bihar. Agreement on Koshi Project 11/6/2008

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1 CHALLENGES IN KOSHI RIVER BASIN Presented by: Naveen Mangal Joshi 1 2 Koshi Basin Drainage Area: 60,400 sq.km. - In Nepal: 27,863 sq.km. (46%) - In China: 32, 537 sq.km. (54%) Av. Annual yield: 1409 cumec Probable Maximum Flood: 35,947 cumec (1 in 1000 years) Annual Sediment Load: 1430 CM/sq.km Highest peak flow observed: 25,880 cumec in Oct. 5, Koshi: A Sorrow of Bihar Major Rennel and James Furgusion reported that oldest Koshi flowed eastward and joined Mahananda; Mr. F.A. Shilling with 25 yrs. observation in 1893 :(i)koshi oscillates between Brahmaputra and mouth of Ganges; (ii) Movement of 0.54 km/yr; Sir C.G. Inglish in 1941 identified excess charge of silt; Dr. A.N. Khosla believed for comprehensive study before proceeding for solution; Study on Koshi high dam and Sunkoshi Kamala diversion in progress with snail s speed? Agreement on Koshi Project Executed in April 25, 1954; Criticism against Koshi Agreement intensified in early 1960s; Indian Power & Irrigation Minister, Dr. K.L. Rao during visit in Nepal in expressed India s rediness to amend the Agreement; Indian Premier, L.B. Shastri further assured in 1965 for revision of the agreement; Revision made was signed in Dec.19,

2 Maintenance and Operation Through a exchange of letter dated Dec.19, 1966: It has been agreed that between our two Governments that the land on which the Nepal Link Bund is situated as shown in Amended Annexture A referred to in sub-basin (ii) of Clause 1, will be surrendered by the Government of India to His Majesty s Government who, on their part will agree to permit the Government of India to maintain and operate the existing waterways in this Bund. Infrastructures in Koshi Basin Structures related to hydropower: Sunkosi, Bhotekosi, Indrawati, Khimti Irrigation Intake structure at Barahchhetra, West Koshi Pump Irrigation, Chandra Canal in Trijuga river River embankment from Chatara to Koshi Barrage Emergent repair works in Chatara and surrounding by GON Koshi Barrage and Embankment portion maintenance by Bihar, GOI 7 8 Koshi River Koshi River Left Embankment Breached on August 18, 2008; More than 60,000 people displaced in Nepal; 3 Million people being affected in Indian side; More than 120 people died; Crops and other property valued millions destroyed 9 Source: OCHA/UNDP 10 Comparative Satellite Image Source: Sentinel Asia 11 Source: Sentinel Asia Enlarged View at Embankment Breached Portion 12 2

3 Source: NASA Earth Observatory Photo: Basistha Adhikari Koshi Afflux Bund: U/S 18 3

4 Photo: B. Adhikari Koshi Afflux Bund: U/S 19 Photo: B. Adhikari East West Highway portion 20 Flooded Area Photo: B. Ahdikari Photo: B. Adhikari 21 Evacuation of People 22 Today s need. Prevention from further damage Closing breached portion Diversion of flow thro Barrage. Reinstatement of highway/road. Confidence to move respective home of the flood affected people Is it possible? Photo: Kantipur Koshi Embankment Protection Work in Progress

5 A small truth to make our plan/program 100% success.. If,. A=1, B=2, C=3, D=4, E=5, F=6,G=7,H=8,I=9, J=10, K=11, L=12, M=13, N=14, O=15,P=16, Q=17, R=18,S=19, T=20, U=21, V=22, X=23, X=24, Y=25 and Z= L+U+C+K = = 47 % H+A+R+D+W+O+R+K = = 98% only K+N+O+W+L+E+D+G+E = =96% only L+O+V+E= = 54% Every problem has a solution, only if we perhaps change our attitude. A+T+T+I+T+U+D+E = = % It is our ATTITUDE towards Life and Work that makes our plan/action 100% success. a truly positive thinking!!! 27 06/11/ Then what are the possible solutions?????? 29 BANK PROTECTION/ RIVER DIVERSION CARRIED OUT BY USING STRAIGHT GROYNES 30 5

6 EMERGENCY WORKS To deter or prevent floods and unexpected erosion caused by water, Gabions provide an efficient and convenient solution. Such structures allow quick interference under any environmental situation or climate, and work can start even at the most critical period of weather hazards. BANK PROTECTION/ SHIFTING OF FLOW CHANNEL WORKS IN DEEP WATER WORKS IN DEEP WATER Filling of gabions at banks and making ready for lifting Placing of gilled gabions inside water WORKS IN DEEP WATER Lifting of filled gabions by crane WORKS IN DEEP WATER Placing of gilled gabions inside water

7 SOLUTIONS FOR EMERGENCY RESTORATION WORKS.. AGAIN ON EMERGENCY WORKS The need for emergency restoration works carried out using in-situ materials in order to prevent flooding of infrastructures or for plant protection always requires innovative solutions. Maccaferri has developed a prefabricated multicellular structure particularly suitable for any type of filling material. FLEX-MAC is a multicellular structure in double twist wire mesh vertically reinforced with metallic bars, spirals or metallic rings: FLEX-MAC can be easily assembled within a few minutes, with little effort. RAPID FILLING OPERATION BY MECHANICAL MEANS 37 Filled units 38 CULVERTS and infrastructure protection CULVERTS AND INFRASTRUCTURE PROTECTIONS CULVERTS and infrastructure protection Gabion Abutment BRIEF OVER VIEW OF GEOTEXTILE BAG APPLICATION

8 GEO-TEXTILE DELIVERED BAGS AT SITE SITE WILL COMMENCE SOON Sand/soil filling in Geo-Textile bag 45 Placing of filled Geo-Textile bag 46 What next?... Activation of Joint Committee on Water Resources Joint Committee on Koshi & Gandak Projects High Level Committee on Koshi (Indian side) Compensation of affected people in Nepal? Siltation/ Agradation of River Problem? Koshi High Dam / Basin Management? Resettlement problem? Climate Change a Current Burning Topic Climate Change. Global Warming expect to increase between 1.4 to 5.8 o C over 100 years; 3,252 glacier lakes in Nepal covering 5,324 sq. km; 20 lakes are potentially dangerous inclusive of 17 no. which experienced early; Koshi Basin with 779 lakes covering 1,409 sq.km.; Around 13 GLOF occurred after 1960 only in Koshi Basin;

9 21.0 Temperature Trend Annual Mean Temperature Trend y = 0.039x R = Glacier Lakes Temperature ( C) Dig Tsho outburst in August 1985 destroying newly built Micro Hydro plant, bridges and other properties; Tsho Rolpa, the only mitigation measure carried Glacier lake; Imja has a history of rapid growth Year All Nepal Temperature is increasing steadily. 1.7 C increase between 1975 and 2005 Source: Dr. Madan Shrestha Himalayan Glaciers are retreating very fastly Imja 15 December 1962 (Corona image) Area 27,916 sqm. ICIMOD Source: ICIMOD 52 Imja 15 October 1975 (Landsat MSS) Area 309,573 sqm. Imja 22 September 1992 (Landsat5 TM) Area 635,945 sqm

10 Let s go and build stronger teams! ALOS 2007 Area = sq m., Length =2027m Source: ICIMOD