XA0202716

IC/IR/2002/10 INTERNAL REPORT (Limited Distribution)

United Nations Educational Scientific and Cultural Organization and International Atomic Energy Agency

THE ABDUS SALAM INTERNATIONAL CENTRE FOR THEORETICAL PHYSICS

CONJUNCTIVE IRRIGATION THROUGH GROUNDWATER FOR CROP PRODUCTION IN EASTERN

S.S. Singh Land, Water, Environment & Engineering Research Programme, ICAR Research Complex for Eastern Region, Walmi Complex, , -801 505, India

A.R. Khan* Land, Water, Environment and Engineering Research Programme 1CAR Research Complex for Eastern Region, Walmi Complex, P.O. Phulwari Sharif, Patna- 801 505, India and The Abdus Salam International Centre for Theoretical Physics, Trieste, Italy

J.P.Singh1 and S.R.Singh2 Land, Water, Environment and Engineering Research Programme 1CAR Research Complex for Eastern Region,Walmi Complex, P.O. Phulwari Sharif, Patna- 801 505, India.

MIRAMARE -TRIESTE May 2002

* Regular Associate of the Abdus Salam ICTP. 1 Chief Scientist & Officer -in- Charge, Irrigation Research Station, Rajendra Agril. University, , Rohtas , - 802 212, India. 2 Vice Chancellor, Rajendra Agricultural University, Pusa, , Bihar- 848 125, India. Abstract

Ground water is the most reliable source for irrigation, quantum of which varies from place to place, rainfall, infiltration, geographical strata and surface ecology. The development of ground water in conjunction with surface within canal commands not only assures a reliable source of irrigation, it also helps in alleviation of water logging in the command due to excess seepage and unscientific water use by facilitating vertical drainage mechanism. The ground water resource needs to be developed in order to enhance area and timeliness of irrigation supply and overall agricultural productivity of land. In the high potential - low productivity areas in Assam, Bihar and West Bengal, A.P. and NE states, there is an immense potential to improve agricultural productivity through systematic groundwater exploitation. Overview Of Groundwater Potential And Utilization In Bihar

Bihar state of eastern India has an area of 94163 km2 having with 60.5 per cent (5.696 m ha.) area under crop cultivation at 144.7 per cent crop intensity (Anonymous, 1997). Irrigation potential through groundwater resources is 3.48-million hectare area. This may cover about 61 per cent net sown area of state. Total availability of ground water resources is 3.373-million hectare meter with good quality for irrigation. The total groundwater potential, utilization and balance potential of Bihar for which basin wise proper and efficient planning is needed are presented in Table 1. Total utilization envisaged through completed and on-going scheme is 1.287 M. ha m. Only 38 per cent of groundwater has been utilized. This shows high scope for further development. The balance groundwater resources of 2.086 million-hectare meters have to be tapped for agricultural production.

Conjunctive Use of Irrigation Water for Crop Production

Rice and wheat are major crops of the state whose total annual productivity (3.29 t/ha) is far below than Punjab (7.48 t/ha) and Haryana (6.16 t/ha) where level of ground water development has been 93.8 and 83.8 per cent, respectively. Effect of conjunctive use of irrigation water on the production mustard and wheat in Gandak Command of Bihar are presented in Tables 4 and 5, respectively. It is proved that even in canal irrigated condition the availability of tubewell water crop could boost the crop yield to respective level. Thus, when canal irrigation was not available normal harvest was possible due to ground water utilization at critical stage of the crop. Conjunctive Irrigation also does not allow the ground water to rise. This keeps at bay the problems of water logging and salinity (Singh et ah, 2002).

Feasibility Structure of Groundwater

Table 2 presents the district wise additional number of groundwater structure feasible in Bihar. District wise irrigation potential scenario is presented so that a proper planning for groundwater structures may be created to supply additional irrigation. Tube well density in Bihar is only 5.9/km2 while in Punjab and Haryana it is 12.36 and 10.47/km2, respectively. Bihar has potential to increase tube well density upto 28.2 km2. Additional 1684182 numbers of groundwater structures are feasible having a combination of 1680665 shallow tube wells and 3517 number of deep tube well. Based upon these facts million shallow tube well projects has been launched by Union Govt. of India to boost up on-farm water management for increasing crop production in Bihar.

Plan Panel's Tubewell Scheme

Minor irrigation department of Bihar has to sink 10.26 lakh million shallow tube wells and distribute 10.26 lakh diesel pump sets of 5 hp at a cost of Rs. 2886.41 crores. Under the scheme, the state government received central grant of Rs. 25.50 crores. With this amount, the minor irrigation department has to sink 33,798 shallow tube wells and distribute equal number of diesel pump sets among farmers in the current calendar year of 2001-2002. Of the centra] grants, Rs. 25 crores has been available to the National Bank for Agriculture and Rural Development (NABARD), which is the implementing agency. Of the total expenditure earmarked for the scheme, Rs. 42.50 crores would be bank loans, while Rs. 17 crores beneficiaries share.

Planning Commission has accorded the mode of development for popularization of shallow tube well with 30 per cent subsidy, 50 per cent loan to beneficiary and 20 per cent beneficiary contribution. All categories of farmers are eligible with preference to SC/ST for availing the subsidy and loan. Total 1.006 million shallow tube well has been proposed with cost of Rs. 2827.71 crores to cover 2.042 m ha land to increase 6.0 million tones additional food grain production.

Aquifer Condition

Aquifer condition (district and division wise) of Bihar is presented in Table 3. In Bihar district wise average depth of aquifers has been assessed. The average depth varies from 20-50 m. and depth of shallow tubewell will vary from 15-25 to 40-60 meters range. The recommended depth of shallow tubewell is 40-60 m in Patna, 30-50 m in Gaya, and divisions of south Bihar. In it is 25-30 m in Saran, 27- 45 m in Tirhut and 25-35 m in divisions. After completion of project 85 per cent groundwater development is expected to exploit. Currently no block of Bihar falls in the over exploited and dark area and only 7 blocks have been found under gray zone.

Ground water development forms the major part of minor irrigation programme and include construction of dug well, dug - cum bore well, filter points, private shallow tube well and deep public tube wells. It is essentially a people's programme implemented primarily through individual and cooperative efforts with finance obtained mainly from the institutional sources. The ground water scheme comprise of open wells/dug wells, shallow tube wells, bore wells, filter points and deep tube wells, where only deep tube wells are state owned and rest are individual owned.

Tube wells and lift irrigation schemes depend on supply of electricity. Since only 14 percent electricity of the state is available for agriculture purpose, therefore, dependency is major upon diesel-operated machines. Bihar geographically falls in the very good category of rainfall zone and has vast ground water reserve of 2.569 million hectares meters. Therefore, the immense scope of creating more irrigation potential by utilizing untapped underground water resources to increase production and productivity should be properly utilized.

Acknowledgments This work was done within the framework of the Associateship Scheme of the Abdus Salam International Centre for Theoretical Physics, Trieste, Italy. References

Anonymous (1997). State Planning Commission Report, Govt. of Bihar, Patna

Singh, S.S., Singh, J.P. and Khan, A. R. (2002). Groundwater utilisation for on-farm management to increase crop production in Bihar. International Groundwater Conference, Dindigul, Tamil Nadu, February 20-22, 2002. Table 1. Total Groundwater Potential, Utilization And Balance Potential For Which Planning Needed (Basin Wise)

SI. Name of Basin Ground water Potential/ Utilization No. Available Utilization Balance (L.ha-m). L.ha-m. Per cent (L.ha-m). 1. Ghaghra, Gandak, 7.31 3.40 46.55 3.91 Burhi Gandak, Mahi &Baya 2. B agmati- Adhwara 1.86 0.79 42.22 1.07 3. Kamla 1.19 0.45 37.56 0.74 4. Kosi 3.70 1.21 32.67 2.51 5. Mahananda 2.31 0.51 22.28 1.80 6. Karmanasa 1.66 0.55 23.96 1.11 7. Sone (including left 2.51 1.15 45.85 1.36 out area of Kanhar) & GmS-KAO 8. North Koel 0.68 0.17 25.40 0.51 9. 2.07 0.88 42.38 1.19 10. Kiul-Harohar 3.09 1.57 50.91 1.52 11. Badua-Belharna 0.59 0.17 30.85 0.42 12. Bilasi-Chandan-Chir 0.89 0.30 35.00 0.59 13. Ganga-Stem 1.56 0.84 53.85 0.72 Total 2.42 11.99 40.75 17.43 Table 2. Additional Number of Groundwater Structure Feasible in Bihar

SI. District Irrigation TYPE & NUMBER OF FEASIBLE GROUND WATER No. Potential to ABSTRACTION STRUCTURES be created Deep Shallow Dugwell Borewell (ha.) Tubewell Tubewell (0.75 ha) (1.5 ha.) (7.5 ha) (2.25 ha) 1 2 3 4 5 6 7 1. Siwan 54334 54 48934 2. 55119 55 24809 3. Rohtas 391992 391 182929 58798 13066 4. Gaya 191773 191 89494 28765 6395 5. Bhagalpur 320285 320 149466 48042 10676 6. Araria 142703 147 66251 7. Saharsa 97254 97 43777 8. 39875 39 23983 9. Samastipur 64462 64 38708 10. Kishanganj 99339 99 44719 11. j Patna 73561 73 22087 12. Bhojpur 152120 152 91280 13. 51330 51 26417 14. 108905 108 96482 5445 3630 15. Gopalganj 68523 68 61723 16. Purnea 137620 137 61960 17. 72440 144 19317 14488 9658 18. Madhepura 49328 49 22214 19. 81256 81 48770 20. 83597 83 37648 21. Darbhanga 71556 71 42970 22. 43598 43 26198 23. 48771 48 29314 24. Aurangabad 162300 190 81150 21099 25. East champaran 125594 125 45237 26. Munger 204815 204 40962 64100 2048 27. Saran 77964 77 0264 28. West champaran 228452 228 82260 29. Madhubani 02214 102 61342 Total 3405580 3517 1680665 219638 86398 Table 3. Aquifer Condition In Bihar

SI. No. Name of District No. of Blocks Depth of shallow Average depth suitable for tubewell (recommended in meter tubewell in meter 1 PATNA 23 40-60 50 2 BHOJPUR 14 40-60 50 3 BUXER 11 40-60 50 4 NALANDA 17 40-60 50 5 ROHTAS 12 30-50 40 6 BHABHUA 9 30-50 40 MAGADH DIVISION 7 GAYA 23 30-50 40 S JEHAN AB AD 10 30-50 40 9 NAWADA 10 40-60 50 10 AURANGABAD 7 30-50 40 TIRHUT DIVISION 11 MUZAFFARPUR 15 25-35 30 12 VAISHALI 16 25-35 30 13 SITAMARHI 18 30-50 40 14 4 30-50 40 15 WEST CHAMPARAN 18 40-50 50 16 EAST CHAMPARAN 26 30-50 40 SARAN DIVISION 17 SARAN 20 25-35 30 18 SIWAN 16 25-35 30 19 GOPALGANJ 14 25-35 30 20 DARBHANGA 16 20-30 25 21 MADHUBANI 20 30-50 40 22 SAMASTIPUR 20 25-50 37 MUNGER DIVISION 23 MUNGER 8 30-50 40 24 BEGUSARAI 17 30-50 40 25 7 30-50 40 26 KHAGARIYA 7 20-30 25 27 6 30-50 40 28 6 30-50 40 BHAGALPUR DIVISION 29 BHAGALPUR 16 30-60 45 30 BANKA 8 30-50 50 KOSHI DIVISION 31 SAHARSA 10 15-25 20 32 MADHEPURA 11 15-25 20 33 11 15-25 20 PURNEA DIVISION 34 PURNEA 14 15-25 20 35 KISHANGANJ 7 15-25 20 36 ARARIA 9 15-25 20 37 KATIHAR 16 15-25 20 Table 4. Effect Of Conjunctive Use Of Irrigation Water On Mustard Yield In Gandak Command, Bihar

No. of Depth of Source Mean S.D. WUE irrigation irrigation yield (q/ha-cm) (cm) (q/ha) 2 12 1T+1C 18.8 1.10 1.56 1 6 1C 11.6 0.62 1.93 0 - - 7.1 - - T= Tubewell, C= Canal, Seasonal rainfall 24 mm Source - Status Report On-farm Water Management RAU, Pusa, Bihar 1992

Table 5. Effect Of Conjunctive Use Of Irrigation Water On Wheat Yield In Gandak Command, Bihar

Outlet No. Fertilizer dose Irrigation Mean yield Number Source (q/ha) 0.65 L Farmers Practice 2 Canal 18.6 (Head) Farmers Practice 2 1T+ 1C 23.1 General Recommended Dose 2 Canal 22.7 General Recommended Dose 2 1T+1C 30.2 4.70 R Farmers Practice 2 Canal 10.2 (Tail) Farmers Practice 2 1T+1C 15.6 General Recommended Dose 2 Canal 13.8 General Recommended Dose 2 1T+1C 18.6 Source - Status Report On-farm Water Management RAU, Pusa, Bihar 1992