Exec Summary
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STUDY ON PLANNING OF WATER RESOURCES OF RAJASTHAN Executive Summary Project Background The State Water Policy of Government of Rajasthan, February 2010, provides for development of its Water resources in a well planned way. All new projects shall be planned based on micro watershed planning basis so as to ensure equity in use of surplus water. It is on this account that the Government of Rajasthan took up study to review and update all River Basin Master Plans for the integrated development and management of all its water resources. In this connection necessary provision of funds were made in EC funded State Partnership Program (SPP) under implementation in Rajasthan State. The earlier comprehensive study on water planning for different river basins in Rajasthan State was carried out by TAHAL-WAPCOS Consultants during year 1994-1998. This study was considered quite old and had much reduced relevance in today’s context. The present study therefore envisages to take-up review and fresh planning of all the water resources of Rajasthan based on updated water resources data and modern techniques now available in this field of study encompassing all necessary provisions made in the new water policy of the State Government. The purpose of this assignment is to prepare a long term plan and policy for development and management of the water resources of the State of Rajasthan, both surface (internal and external) and ground water, on comprehensive and integrated basis. The period of planning envisaged is 2010-2060. Scope of Work 1. Data Collection 2. Analysis of Agroclimatic Zone wise hydrology, temperature over a period of 20 years, find all changes in precipitation, no. of rainy days, rainfall intensity, temperature, humidity and the impact on water resources, cropping pattern and productivity and suggest futuristic strategies for water uses, cropping pattern, in view of the changes. 3. Study the basin wise / sub-basin wise water availability (at various dependabilities) both surface and ground water (including interstate share of Rajasthan from Ravi, Beas, Satluj, Chambal, Mahi and Yamuna Water), indicate changes as compared to the earlier TAHAL-WAPCOS Study with reasons for change. 4. Carry out detailed study of the catchment areas of all major, medium and minor irrigation projects, identify the WHSs constructed and the watershed works carried out and mark the same on GIS mapping with requisite hydrological details and assess their impact on water flows to the project, study the transevaporation of these small water bodies and resultant water loss, their impact on ground water recharging and suggest a future policy for construction of such structures in the catchment area. 5. Agroclimatic Zone wise ground water basins studies, delineation of aquifers on microshed basis, marking them on the GIS mapping Panchayat Samiti wise Report # 4.9 – IN-24740-R13-080 October, 2014 Integrated State Water Resources Plan Executive Summary Page i STUDY ON PLANNING OF WATER RESOURCES OF RAJASTHAN and Village wise, based on the present exploitation and recharging of aquifers compute the remaining life of the aquifer so that this information could be disseminated Panchayat Samiti & Village wise. 6. Estimate the quantity of Water Pollution (Rivers, Industrial, Municipal etc.) Source wise, District wise and indicate costs of reclamation / treatment and possible uses. 7. Prepare Districtwise and Blockwise plans of supply and demand of water for various uses, crops, strategies to fill gap and estimated costs. 8. Identification of new projects in water surplus basins based on scientific study and survey and based on socio economic viability criteria. 9. Identification of projects for rehabilitation and/ or modernisation for existing major and medium projects based on socio economic viability criteria. 10. Preparation of comprehensive full scale integrated water resources plan for the State as a whole. 11. Imparting training to the staff and officers of SWRPD & WRD on planning and on use of software used in the study. Integrated State Water Resources Plan This report on Integrated State Water Resources Plan is the last one in the series of nine Final Reports. The objective of this report is to present a comprehensive full scale integrated plan for the State as a whole as well as to summarize the various aspects covered under other reports of this study on Planning of Water Resources of Rajasthan State and their conclusions and recommendations in form of an Action Plan highlighting responsible agencies for execution of the plans. Project Related Features of Rajasthan Rajasthan is the largest state in the Indian Union, with an area of 342,264 km 2. It is located in northwest India between longitudes 69°29’ and 78°17’ East and latitudes 23°30’ and 30°11’ North. The Tropic of Cancer passes through Rajasthan south of Banswara town. Rajasthan features a variety of landforms, which have resulted from erosional and depositional processes over a long geological time period. Four major physiographic divisions have been identified in the State: • Aravalli Hill Ranges, • Eastern Plains, • The Thar Desert, and • The South Eastern Plateau. The topography, rainfall, and geology are the most important factors affecting the extent and orientation of drainage, in Rajasthan in general and within a basin in particular. Report # 4.9 – IN-24740-R13-080 October, 2014 Integrated State Water Resources Plan Executive Summary Page ii STUDY ON PLANNING OF WATER RESOURCES OF RAJASTHAN The geological sequence of the State is highly varied and complex, showing the co- existence of the most ancient rocks of Pre-Cambrian age and the most recent alluvium, as well as wind-blown sands of Quaternary to Recent age. A total of 19 hydrogeological units have been identified on the basis of CGWB and RGWD data base. The significant and mapable hydrogeological units are considered to serve the purposes of water resources planning. The hydrogeological units were delineated using water-bearing formation data of CGWB and RGWD. The same have been delineated on micro-watershed, using GIS, and also panchayat samiti-wise (block-wise) and village-wise. Major 19 Hydrogeological Formations and their Areas in Rajasthan S. No. Hydrogeological Units / Hills Area, Km 2 1 Younger Alluvium 48,070.05 2 Older Alluvium 94 ,968.09 3 Tertiary Sandstone 24,502.65 4 Deccan Traps (Basalt) 9,580.51 5 Jurassic Sandstone (Lathi, Parihar, Baisakhi, Bhadesar) 15,213.07 6 Vindhyan Sandstone (Nagaur, Jodhpur) 25,675.64 7 Bilara Limestone 9,522.51 8 Bhander Sandstone 13,954.29 9 Limestone (Alwar, Bhander, Upper Cretaceous) 4,853.08 10 Shale 3,906.68 11 Quartzite 5,325.02 12 Slate 367.65 13 Phyllite & Schist 35,728.18 14 Gneisses 1,967.40 15 Jalore Granite 5,612.72 16 Erinpura Granite 5,229.75 17 Rhyolite 5,046.40 18 Ultra Basics 107.72 19 Gneisses(B.G.C.) 21,724.31 20 Hills 10,908.08 Total 342,263.80 Climate Average annual rainfall of the state is 604 mm and average annual monsoon rainfall is 531 mm. The state has large variance in the climatic conditions. The distribution of rainfall, both over time and area, is highly uneven and erratic. The extreme hydrological events, floods and droughts, are usual features for the State. The maximum temperature is highest in (37.4°C) the pre-monsoon season, while it is lowest (25.7°C) in cold weather season. Mean annual maximum temperature in Rajasthan is 33.2°C with a range of 25.7°C - 35.0°C. Minimum temperature attains its Mean highest value (25.1°C) during monsoon season, while it attains its Mean lowest value (9.6°C) in cold weather season. Mean annual Minimum temperature within Rajasthan is 19.1°C with a range of 11.8°C - 21.8°C. Report # 4.9 – IN-24740-R13-080 October, 2014 Integrated State Water Resources Plan Executive Summary Page iii STUDY ON PLANNING OF WATER RESOURCES OF RAJASTHAN Highest Maximum temperature attains its maximum value during Pre-Monsoon season (44.7°C) while it is lowest during Cold Weather season (34.6°C). Lowest Minimum temperature attains it lowest value during Cold weather (1.2°C) while it is highest during Monsoon season (17.8°C). The highest mean monthly rainfall occurs in the middle months of July and August, with 198.4 and 164.0 mm respectively in each month, contributing about 67.1% of the annual rainfall, while June and September rainfalls contribute 10.5% and 14.0%, respectively. It is observed that contribution of the other three seasons to annual rainfall is marginal. Winter, pre-monsoon and the post-monsoon seasons contribute 2.2%, 3.4% and 2.8%, respectively. Evaporation in Rajasthan is highly variable, both in spatial and temporal terms. Annual evaporation ranges from 140 cm to over 300 cm over the State. Values exceeding 300 cm occur over western Rajasthan (observed at the IMD weather station in Jaisalmer), which mainly comprises a desert area. It is generally the highest during May (when it ranges from about 26 cm to 43 cm) over most parts of the State and continues to be high in June too. The minimum usually occurs in December and January, when evaporation ranges from about 4 cm to 12 cm per month. Relative humidity follows a sinusoidal pattern, decreasing from 54.7% in January to a minimum of 30.5% in April, increasing to a maximum of 72.6% in August, and again decreasing to 48.4% in October. Trend analysis of different weather parameters have been studied during the past 20 years and impact of change in weather parameters on cropping pattern, productivity and water resources and future strategies in view of change in weather have been presented in detail in Final Report No.