Water Table Behaviour in Punjab: Issues and Policy Options
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WATER TABLE BEHAVIOUR IN PUNJAB: ISSUES AND POLICY OPTIONS Karam Singh* Abstract Punjab faces a sever problem of declining water tables by as much as 10 – 15m in most parts. The paper focuses on groundwater behavior in various parts (Blocks) of the Punjab in categories of low to high rainfall regions, saline to sweet groundwater zones, scanty to extensive canal water supply areas, the uplands to riverbeds and the cropping pattern in terms of low to high water intensive crops. Any changes in these parameters will affect the recharge and withdrawal of groundwater. In was found that as the area under rice cultivation increased, there was a corresponding decline in ground water recharge. It is often advocated that pricing policy for wheat and rice (Minimum Support Price (MSP) and its effectiveness) and free electricity supply are responsible for the critical ground water situation in Punjab. The paper tires to examine this and look at policy measures needed to address the situation. 1. INTRODUCTION The groundwater situation in Punjab has been a serious issue for a long time now. The total water requirement for Punjab, with the present cropping pattern and practices and industrial uses, is estimated at 4.33 million ha metres. It varies from 4.30 to 4.40 million ha metres. The total availability of water is estimated at 3.13 million ha metres out of which 1.45 million ha meters is from canals and 1.68 ha meters is from rainfall and seepage. The deficit of almost 1.20 million ha metres is met by ground water withdrawal. The recharge rate is not able to match the rate of withdrawal. This has led to a decline in the water table in Punjab1 The annual rainfall in Punjab ranges from over 300 mm in 21 rainy days in the Western part to over 1100 mm in 48 rainy days in the North and North Eastern part. Mean annual rainfall during 1973 to 2005 was 600 mms in 32 rainy days. Almost 80 % of the rainfall comes in the monsoon period with about 57% falling in the months of July and August. Monsoon rain recharges groundwater for use during the remaining period. The heaviest rainfall of 1123 mm was recorded in 1988, when there were floods in the entire state. In 1997, the state received 709 mm rainfall, which was more than the state average. There are three major perennial rivers - the Ravi, the Beas and the Satluj – in Punjab and their water is stored at Bhakra Dam, Ranjit Sagar Dam and Pong Dam respectively. This water is supplied through a vast canal network of about 14500 kms including distributaries and minor canals to irrigate about 1.6 million hectares (m ha) of land. The canal water supply is more extensive in the South western zone of the State, which receives less rainfall and high salinity in groundwater. This is the cotton-wheat dominant cropping belt and covers about 34 % of the cultivated area of the state. Out of the total net sown area 96% is irrigated. The entire irrigated area is double cropped every year with a cropping intensity of 187 %. Rice and Wheat cover about 75 % of the total cropped area in the state. There are 11.44 lakh tubewells (8.56 lakh electricity operated) for groundwater abstraction for irrigation. The paper focuses on groundwater behaviour in various parts (blocks) of the state in categories of low to high rainfall regions, saline to sweet groundwater zones, scanty to extensive canal water supply areas, the Professior and Head, Department of Economics and Sociology, Punjab Agricultural University, Ludhiana. 331 uplands to riverbeds and the nature of cropping pattern in terms of low to high water intensive (application, actual and tolerance vs requirements) crops. Any changes in these parameters will affect the recharge and withdrawal of groundwater, which is simulated. It is often advocated that pricing policy for wheat and rice (Minimum Support Price (MSP) and its effectiveness) and free electricity supply are responsible for the critical ground water situation in Punjab. The paper tires to examine this and look at policy measures needed to address the situation. 2. DATA AND METHODOLOGY Hydrologically and agro-climatologically, Punjab is divided into three distinct zones - Foothill, Central and South-Western zones.2 To study the movement of water table, which is significantly affected by the rivers flowing through the state, it is better demarcated into three regions, which are also culturally and historically called Majha (Between Ravi and Beas rivers – 29 Blocks), Doaba (Between Beas and Satluj rivers – 30 Blocks) and Malwa (South of Satluj river – 73 Blocks). The study is based on the data monitored and collected by the hydrological division of the department of agriculture, Government of Punjab since 1973. To begin with, the Department of Agriculture selected open (observation) wells and started recording the depth of water level in these wells during June (pre-monsoon period) and October (post-monsoon period) between the 10th to 25th of the month. When one observation well dried up, another well in the same village was selected. Later Piezometer wells (PZ meters) were installed. As many as 1842 observation points (wells and/or piezometer tubes) have been set up, though the maximum number of observations at any point of time were only 708. This was because some of the observation wells dried up in between. (This is a preliminary indicator of the enormity of the problem of depleting water table). Each block carries a number of observation wells but the water table movement does not necessarily follow the block boundaries. Thus grouping of blocks into regions and sub-regions was difficult. Matching was done following the principle of continuity at the same time trying to include every block in every sub region using individual judgment3. The impact of rice area on groundwater table was scanned by observing the change in recharge during the monsoon season in those years which received almost similar rainfall. The area was scanned for each region along with the corresponding withdrawal during the rabi season. The recharge required to strike a balance was estimated using regression of recharge on rainfall and rice area. To correct the water balance measures such as maximizing efficient surface water use, reducing water demand by restructuring incentives (competitive pricing of electricity for irrigation) and improving the water use efficiency are suggested. 3. WATER TABLE BEHAVIOUR IN PUNJAB AND ITS DETERMINANTS An overview of the water table behaviour (Table 1) shows that although the water table in Punjab has been declining over a large area, there is a belt of 9 blocks in the south west of Malwa Region where the water table has been rising (Map). 2 These zones are: 1. Foothill Zone/ Kandi Area: 19 % area; Gurdaspur, Hoshiarpur and Ropar; Annual rainfall =950mm, groundwater is sweet but in areas difficult to explore 2. Central Zone: 47 % area, Amritsar, Kapurthala, Jalandhar, Ludhiana, Sangrur and Patiala Annual rainfall = 650 mm, groundwater sweet and extensively used; Water table declining 3. South Western Zone: 34 % area; Ferozepur, Faridkot and Bathinda. Annual rainfall = 400 mm, groundwater saline, canal water more extensive & precious 3 The readers may feel that some other sub region or blocks should have been included and not the ones chosen for study. 332 The riverbed region has 35 blocks with each region (Majha, Doaba and Malwa) having 10 – 14 blocks. It is a rice growing area, though traditionally rice was grown more in the Majha and Doaba regions4. The water table in the riverbed blocks has been declining only gradually. The central block consists of 50 blocks out of Table 1: Preliminary scan of water table situation, region wise, Punjab, 1973 to 2006 Particulars Majha Doaba Malwa Total Number of observation point: Installed so far 430 464 948 1842 Actual: June 1973 145 141 288 574 Actual: June 2006 159 169 262* 590 Maximum 178 171 359 708 Number of Blocks Total 29 30 73 132 As river bed 11 14 10 35 Water Table behaviour (No of blocks) Rising 0 0 9 9 Static / fluctuating@ 7 9 18 34 Declining 22 21 46 89 Rate of decline: Gradually 18 11 27 56 Severe: Around 10 metres or more 4 10 19 33 Severest: More than 15 metres 1 2 9 12 Water table level Up to 5 12 → 1 6 → 1 29 → 11 47 → 13 1973 → 2006 5 to 10 14 → 12 20 → 7 32 → 17 66 → 36 (meters) 10 to 15 2 → 11 4 → 7 3 → 21 9 → 39 15 to 20 1 → 1 0 → 10 4 → 17 5 → 31 Above 20 0 → 1 0 → 5 5 → 7 5 → 13 Water table behaviour zones: I. Rising 0 0 9 9 II. River bed (Gradual decline) 11 14 10 35 III. Central: Going deep 10 6 13 31 “ deeper 1 1 13 16 “ deepest 0 0 6 6 IV. Other: Fluctuating, generally 7 9 22$ 36 static, declining lately 4 The river beds on both sides of the river taken together makes the Majha and Doaba Central regions look smaller. Rainfall and Rivers in Punjab is given in Annexure 2. * Relates to 2005 @ Some adjoining blocks with few observations are clubbed and considered as one block $ There is declining water table since 1999 or so in some of these blocks of which 6 are in the East, 9 in middle south and remaining in the west of Malwa region. 333 which 8 blocks are in Majha, 10 in Doaba and 32 in Malwa. Rice is intensively cultivated here. The water table here has been declining at varying degrees. The Foothill or Kandhi zone in the North / East side comprises 22 blocks and has a fluctuating water table and though the water is sweet, exploration is difficult.