Government of Rajasthan Ground Water Department GROUND WATER LEVEL SCENARIO IN RAJASTHAN - 2015 Pre and Post Monsoon survey - 2015 DATA STORAGE AND PROCESSING CELL (DSPC) MAY, 2016 CONTENTS Page. No. 1.0 Overview 1 – 3 1.1 Climate 1 1.2 Rainfall 1 1.3 Physiography 1 1.4 Drainage 2 1.5 Hydrogeology 2 2.0 Abstract 4 3.0 Scenario Of Groundwater Level In Rajasthan – Year 2015 5 – 9 3.1 Depth to water level Pre Monsoon – 2015 5 3.2 Depth to water level Post Monsoon – 2015 6 Change In Water Level (Fluctuation) Pre Monsoon - 2015 To 3.3 8 Pre Monsoon – 2015 4.0 Rainfall condition – 2015 10 FIGURES 1 Aquifer Distribution Map of Rajasthan as per ROLTA Study. 11 2 Depth to water level map of Rajasthan - Pre Monsoon 2015 12 PLATES District Wise Average Depth To Water Level Of Pre Monsoon 1.1 to 1.4 13 – 14 2015 And Post Monsoon – 2015 2.1 to 2.2 Change in water level pre monsoon & post monsoon – 2015 15 3.1 to 3.2 Rainfall condition of all the districts during 2015. 16 TABLES District Wise Average Depth To Water Level During Pre 1 17 Monsoon and Post Monsoon 2015 Block Wise Average Depth To Water Level And Fluctuation 2 18 – 25 During Pre Monsoon 2015 And Post Monsoon 2015 Normal Monsoon, Non monsoon, Annual Rainfall & Rainfall 3 26 – 27 Condition 2015 Depth To Water Level Data Of Key Wells During Pre 4 28 – 155 Monsoon and Post Monsoon – 2015 1.0 OVERVIEW Rajasthan, the largest state of India with geographical area of 342230 Sq.km. and situated in the north-western part of the country. It extends between 230 30’ and 300 11’ N latitudes and 690 29’ & 780 17’ E longitudes. According to 2011 census population of the State is 68548437. The state has been divided into 33 districts and further in 295 developments blocks. 1.1 Climate The Aravalli range divides the state into two different climatic zones. The region west of Aravallis is desert to semi-desert and east of Aravallis is semi arid to sub-humid and characterized by large extremes of temperature long periods of drought, high wind velocity and high potential evapotranspiration. Based on the weather conditions, three distinct seasons are in the state – (i) Hot-weather season (March to end of June) (ii) Monsoon season (end of June to September) (iii) Cold-weather season (October to February) 1.2 Rainfall During the monsoon period of 2015 there were wide variation of rainfall in extreme Western part and South –Eastern part of the State like 185 mm. annual rainfall is received in Jaisalmer, (extreme Western part), while 970 mm. annual rainfall is received in Jhalawar, (South – Eastern part). The annual normal rainfall of the State is 594.9 mm. out of which 75 to 95 % of the rainfall mostly precipitates in the monsoon period i.e. from 1st June to 30th September. The normal rainfall of the State for the monsoon period is 530.1 mm. 1.3 Physiography The state has a fairly motive topography developed during the long period of denudation and erosion. The present physiography and landforms are greatly determined by the underlying geological formations and structures and are the product of the fluvial cycle of erosion in the past and the recent and GW Level scenario in Rajasthan - 2015 1 continuing desert cycle of erosion. The state can be divided into four physiographic units – (i) Aravalli Hill ranges. (ii) Eastern plains (iii) Western sandy plain with sand dunes (iv) Vindhyan scarpland and Deccan Lava Plateau 1.4 Drainage Aravalli Hills ranges form the main water divide in the state. Luni river is the only river in the west Aravallis and rest 60% area of western Rajasthan has internal drainage and the streams are lost in the desert sands after flowing for a short distance from the point of origin. The Chambal catchment occupies 21% (72032 sq.km) of total geographical area of the State. The other important catchments are Yamuna-Ganga in the north-east and Mahi and Sabarmati in south-west part. In desert area, a few salt lakes and depressions exist, prominent among them are the Sambhar lake, Didwana lake, Bap, Pachpadra and Rann of Jaisalmer and Pokran. 1.5 Hydrogeology The principal source of recharge to ground water in state is rainfall. In canal irrigated areas, a part of canal water through seepage. The geological formations are divided in two groups broadly on the basis of their degree of consolidation and related parameters. (I) Porous Formations (a) Unconsolidated Formations – The Quaternary sediments comprising of younger and older alluvium composed of clay, silt, sand, gravel and form potential aquifers. The yield of exploratory tube wells in alluvium formation is medium to high ranging from 36 to 360 m3/hrs. (b) Semi Consolidated Formations – These formations composed of siltstone, claystone, sandstone, shale conglomerates and limestone of Paleozoic, Mesozoic and Cainozoic age. The sandstone and GW Level scenario in Rajasthan - 2015 2 limestone forms good aquifer in various district of state. Ground water occurs under semi-confined to confined conditions. (II) Fissured formation Fissured formations as hydrogeological unit occupy 32% area of the state and divided into four units- (a) Consolidated sedimentary rocks (b) Igneous and metamorphic rocks (c) Volcanic rocks (d) Carbonated rocks The development of ground water resources in Rajasthan has passed through various phases starting with meager irrigation of pre plan era, the ground water is now providing irrigation to more than 55% area and catering the drinking water needs of about 80% water supply schemes. The demand of industrial need is increased many fold in last 2-3 decades. The rapid and haphazard exploitation of ground water has resulted in declining water levels, gradual exhaustion of ground water reservoirs and deterioration of ground water quality. This is evident from the fact in the year 1984 irrigation draft was 4926 mcm with stage of development 35.75% only where as in 2011 the irrigation draft is estimated 13133.1818 mcm and stage of development 137.07%. Looking to present status of ground water resources in the state it has been realized that ground water management and its judicious use with public participation should be taken up on priority. GW Level scenario in Rajasthan - 2015 3 2.0 ABSTRACT The pre monsoon and post monsoon hydrogeological survey, 2015 of the State of Rajasthan has been carried out during the months of May – June and Oct – Nov 2015 respectively. A monitoring network comprising dug wells and piezometers located in all districts of the State was monitored during the survey. There are 8066 water level monitoring stations (District Key wells) which includes 2879 piezometers spread all over the state. Water level is available in 5545 and 5614 during pre monsoon and post monsoon survey 2015 respectively. Other monitoring stations, in which water level is not available, are either dried up or water level has gone deep in the boring or could not be measured due to one or other reason. The average depth to water level of blocks and districts of pre monsoon, 2015 and post monsoon, 2015 has been analysed to know the depletion or rise of water levels during the year 2015. (Table-1 to 2). The change in water level between pre monsoon 2015 and post monsoon, 2015 referred as annual (seasonal) water level fluctuation. While computing pre monsoon 2015 depth to water level data it is observed that depth to water level ranges between 0.70 mtrs to 153.20 mtrs below ground level. Lowest water level reported at three places. These are – Sarwar (Arain block) of Ajmer district, Lohagarh (Kaman block) of Bharatpur district and Mandal (Mandal block) of Bhilwara district. Highest water level was reported at Nadia Kallan (Baori block) of Jodhpur district. Average depth to water level of the state is computed as 23.16 meters below ground level considering all wells giving water level. While computing post monsoon 2015 depth to water level data it is observed that depth to water level ranges between 0.08 mtrs, i. e. just on ground level, at Charna Bhundwai in Ghatol block of Banswara district to 152.92 mtrs below ground level in Kharia Khangar village (Block Bhopalgarh) of Jodhpur district. Average depth to water level of the state is computed as 21.24 meters below ground level. Looking to the above figures it is observed that an overall rise of 1.89 metres has been observed in the state from pre monsoon to post monsoon 2015. GW Level scenario in Rajasthan - 2015 4 3.0 SCENARIO OF GROUND WATER LEVEL IN RAJASTHAN - YEAR – 2015 The pre monsoon and post monsoon hydrogeological survey, 2015 of all the 33 districts of the State of Rajasthan has been carried out during the months of May and June, 2015 and October and November, 2015 respectively. In all 8066 monitoring stations comprising dug wells and piezometers have been monitored during pre monsoon and post monsoon, 2015. The average of depth to water level of blocks and districts of pre-monsoon and post-monsoon along with change in water levels has been computed and results are shown in Tables 1 and 2. These water level data are used to know trend of water levels during pre monsoon and post monsoon period. The average depth to water level (Plate 1.1 to 1.4) and change in water levels (Plate – 2.1 to 2.2) in all the 33 districts of the State during pre monsoon and post monsoon 2015 are displayed through bar diagrams.