Bulletin of Hydrogeological Association, Vol. 5, September 2020 Maharjan S, Shakya N, 2020

Groundwater irrigation of , Nepal: Status, trends and challenges Surendra Maharjan1* and Nir Shakya 2 1 Groundwater Resource and Irrigation Development Division, Banke, Nepal 2 Trichandra Multiple Campus, Ghantaghar, Nepal *Corresponding e-mail: [email protected]

Received: 14 April 2020/Accepted: 22 August 2020

ABSTRACT The study attempts to collect scare and scatter data of groundwater irrigation carried by government agencies in Bardiya district. The district lies in the western part of Nepal, Province 5, which is also known as the 'food basket' of the country. In the past few years, there are lots of groundwater irrigation developments in the district. The data of groundwater irrigation shows that there is a rapid growth of groundwater irrigation after 2007. The present article tries to show groundwater status, trends and challenges of groundwater irrigation in the last few decades of the district and also update the groundwater irrigation potential map of the district.

Keywords: Groundwater irrigation; development; potential map

INTRODUCTION Nepal is primarily an agrarian country, agriculture Groundwater irrigation is carried out by millions development is at its earlier stage in terms of of independent farmers, often with no planning or mechanization, application of various agricultural control on the part of governmental authorities and inputs and availability of irrigation (Chapagain 2018). explains as an excellent catalyst for social and economic A spectacular increase in groundwater use for irrigation transition. According to the Nepal National Sample has taken place in arid and semiarid countries over the Census of Agriculture 2011–2012 (Central Bureau of last few decades. claims 60% of India’s irrigated Statistics 2012), large part of Nepal’s cultivated land areas are served by groundwater wells; independent area (40%) is reportedly reached by canal irrigation surveys suggest the figure may well be 75%; and schemes, but considerably less is used but an estimated even more, if conjunctive use areas are included. 42% of Nepal ’s farmers do have access to Much the same is true of Pakistan, Nepal Terai and groundwater irrigation. Managing scare and scatter Bangladesh. Governments and donors have invested data and keeping records of up-to-date groundwater heavily in building major dams and canal irrigation irrigation status of every district of Nepal Terai play a projects in these regions; but, as of now, by far the bulk vital role in the sustainable development of agriculture of the irrigation and livelihood benefits are delivered and further research in the water resources sector of by groundwater wells (Shah 2005). Groundwater Nepal. So, the article attempts to highlight the status, development is still in the initial stages in Nepal and trends and challenges of groundwater irrigation of last enough groundwater resources to irrigate nearly one- few decades of the district carried out by government half of the agricultural land in Nepal Terai (Kanskar agencies including Department of Water Resources and 2011). According to him, groundwater irrigation can Irrigation, (GoN), Groundwater play a central role in poverty alleviation and contribute Resource Development Board, GoN and Groundwater to improving food security in the country. Groundwater Irrigation and Development Division Office, Banke, irrigation is also described as a silent revolution and a Province 5 Government. potential source of social conflict (Llamas & Martínez- Santos 2005).

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THE STUDY AREA forest. It has 47,233.50 ha agriculture land which is 1.79% to the total agriculture land of the country and The Bardiya District is located in Province 5 in western it is 22.87% of the total land of the district (District Nepal covering 2,06,500 hectares (ha) area (Fig. 1). The Profile 2017). The altitude of this district varies from district consists of eight out of which 138 m to 1279 m. Elevation decreases from north to 6 are urban municipalities: , south. Tharus are the main indigenous ethnic group of Madhuban Municipality, Municipality, the district. But in later days, ethnic diversity has been Municipality, Municipality increased due to in-migration from the outer districts. and Rajapur Municipality and 2 rural municipalities: Karnali River borders west and north, Maankhola River Badhayatal Rural Municipality and Geruwa Rural bordering east, flows almost in the middle Municipality. The average length of the district is 64 of the district. Most of the surface irrigation projects km and breadth is 35 km. Most of the district (68.76%) are supported by these perennial Karnali, Babai and is low land Terai and the remaining part (31.24%) is Maan Khola rivers. Siwalik Hill and its foothills are almost covered by

Fig. 1: Location map.

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DEVELOPMENT STATUS, TRENDS 39.60 m. Based on these all investigation GRDP/ GDC, AND PAST EXPERIENCES 1994 published hydrogeological map of the region showing groundwater irrigation potential in the district Bardiya district commonly known as the 'food basket' is 39,582 ha and also categorized STW potential area of the western part of the country is endowed with and DTW potential area. In the case of production enormous storage of groundwater in the form of wells used for irrigation purposes, Irrigation Lind both unconfined and confined states. Department of of Credit Project (ILC) Project and Nepal Irrigation Water Resources and Irrigation and Groundwater Sector Project (NISP), in 1993 were implemented; Resources Development Board (GWRDB), Field the cluster identification programme constructed Office , Banke, Government of Nepal (GoN) one DTW at Gulariya Municipality which was later are central levels government are for investigation and developed for irrigation purpose for 60 ha land. From research purpose whereas Groundwater Resources 1994 to 2000, 14 DTW irrigation projects namely and Irrigation Development Division Office, Banke the Shantipur-Jamini DTW cluster were constructed is province-level government organization for irrigating 560 ha land. From 2016 to 2018, Irrigation identification of groundwater irrigation potential and Water Resources Management Project (IWRMP) area with development and implementation of deep project constructed 10 DTW irrigating 400 ha in the tubewell (DTW) and STW irrigation schemes. Sanoshree- area. Besides these, from 2009 to 2019, 16 DTW of 570 ha irrigated land has been In the present context, surface irrigation is constructed under different projects. The total irrigated generally cheaper (it is because farmers have to pay land by 42 numbers of DTW within the last 25 years Irrigation Service Fee (ISF) only) than groundwater is 1,470 ha land. From 1993 to 2019, 6801 numbers but many farmers prefer groundwater in the region of STWs were constructed irrigating 14,619 ha land. because it is easily accessed which is beneath their The total land in the Bardiya district irrigated by small farmland and simple in construction technology groundwater both STW and DTW irrigation project is which makes groundwater obtained individually, 16,089 ha. The year-wise development of groundwater thus bypassing negotiations with other farmers and irrigation with corresponding irrigated land is shown government agencies, often an arduous task. Another in Table 1. more important motive is the resilience of aquifers to dry periods. Farmers also practice conjunctive use There are not any major challenges in groundwater within the surface command area, whenever surface pumping like a decline in groundwater table and no water not available they use groundwater. But the environmental issues due to groundwater overdraft important thing is for many irrigated cash crops, which and no deterioration in quality. It is, therefore, to get usually require large investments from farmers, depend alternative irrigation to surface water or year-round today on groundwater, either totally or on conjunctive irrigation in the district, remaining potential hector of use with surface water. Due to these reasons, there is land as mentioned (around 23,500 ha.) has to be covered high demand in tubewell irrigation in the region there is by shallow or deep tube wells as per the potentiality in a demand of 2660 ha by farmers for the next year 2021 a given map. Farmers of the existing area are much in Groundwater Resources and Irrigation Development more familiar in shallow tube well operation and Office, Banke. its management, in case of deep tube well irrigation system, farmers towards operation and management There are altogether 60 DTWs (Figure 2) in the (O and M) of water distribution is most necessary but district including 19 investigation DTWs of United they are not so well familiar. States Agency for International Development (USAID)/ GoN. Investigations of groundwater in the district The whole package of the DTW system includes were done from 1969 to 1972 under United States DTW drilling (depth varies), electrification with 50 kVA Geological Survey/ Nepal Government constructing 19 distribution transformer, pump house, unplasticized DTWs of an average depth of 160 m and a maximum Polyvinyl Chloride (uPVC) buried water distribution depth of 369 m at Dhakela Village which are not in system, submersible pump supply & installation, etc. function. Similarly, 19 investigation STWs were It is also required to discuss existing mode and past constructed from 1989 to 1990 of an average depth of experiences of operation in DTW Irrigation system.

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In Irrigation Policy 2049, GoN shares 85% of total cost clearly defined, so major & minor maintenance has to and the remaining 15% is kind and/ or cash contribution be defined in terms of expenditure of money. Similarly, of a farmer during the construction period, which is i) periodic training should be conducted in time to time implemented in that area where STW is unfeasible. in the near future to run the DTW irrigation projects It is the demand-driven project with 0.5% of total efficiently ii) electrical transmission line has tobe construction cost as upfront cash (later, completion handed over to Nepal Electricity Authority (NEA), and commissioning of the system it can be converted to get the service so quickly, iii) minimum charge for to maintenance and another expenditure fund to users electricity should be fixed by the Government as per and bank account operates with the representation the pump running hours, iv) only technical training is of related GW Irrigation office in the district). In not sufficient for pump operators accounting as well the case of maintenance, GoN part 75% and farmer as organizational management training have to be contribution part is 25% of the total cost. But after introduced, v) demand charge should be free during the amendment in 2070, In Irrigation Policy 2070 farmers stoppage of pumps by some problems and vi) electric have to borne 3% for new DTW construction, 5% for transmission line installed by the Department of pump installation and equipment, pump house and Irrigation (DOI) and GWRDB to run the submersible distribution system. For electrification with 50 kVA pump is not handed over to NEA. To run the GW transformer installation works, farmers do not have to irrigation system efficiently, quoted experiences have to share the contribution. In maintenance, the GoN share be addressed in the future for sustainable development is 80% and farmer share is 20% of the total cost. But in in the agriculture sector. the policy, major and minor maintenance works are not

Fig. 2: Tubewell location map of Bardiya district.

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POTENTIAL OF GROUNDWATER sediments and transmisivity values between 380 and IRRIGATION 550 m2/ d (GWRDB/ UNDP, 1991). Similar materials and potential seem to exist in the eastern part of the The area lies in the Indo-Gangetic basin (IGB) alluvial district around the Maan River. So these areas are aquifers which is significant groundwater potential in potential for STW irrigation development. The area vast deposits of Quaternary Period sediments by the of good potential for STW is 13,202.92 ha and the perennial rivers (Mukherjee et al. 2015) which indicate marginal potential area is 26,379.07 ha (Fig. 4). Bhabar the area is a high potential for groundwater irrigation. Zone in the northwest at the Bansgadhi area consists of According to GWRDP/ GDC 1994, total potential land coarse sediments with deep water levels of more than for groundwater irrigation potential land is 39,582 ha, 7 m potential for submersible pumps facility STW. In which is 83.80% to the total agriculture land of the the south of the district at the central part at Kalika district. The western part is associated with coarse village area mixed sediments of clay, silt, fine to coarse sediments of the Karnali River so lithologically excellent sand with gravel indicating poor potential area. Nepal consisting 30 to 100% aquifer and permeabilities 90 to government has invested heavily in building major 200 m/d. In the eastern half of the district, there is a dams and canals in these regions including Babai small southern central lobe where the shallow aquifer Irrigation Project and Bheri Babai Multiple Project; deteriorates and slightly larger, overlapping with poor but, as of now, by far the bulk of the irrigation and deep aquifer permeabilities below 20 m/d and this in livelihood benefits are delivered by groundwater wells conjunction with areas of deep water table piezometry. in the upland and tail end of the projects. These projects The area of good DTW irrigation potential is 29,786.89 have developed its command area only in the south part ha and the marginal potential area is 9,795.10 ha land of the East-West Highway and the remaining northern (Fig. 3). STW lithological analysis indicates that in part of 6,093 ha land the only source of irrigation is much of central and west Bardiya consist of coarse groundwater.

Table 1: Development of Groundwater Irrigation Shallow tubewell Deep tubewell Year Total irrigated land (Ha) Number Irrigated land (Ha) Number Irrigated land (Ha) 1996 0 0 8 320 320 1997 0 0 1 40 40 1998 0 0 4 160 160 1999 118 295.0 1 40 335 2000 0 0 1 40 40 2001 0 0 0 0 0 2002 0 0 0 0 0 2003 0 0 0 0 0 2004 0 0 0 0 0 2005 0 0 0 0 0 2006 40 100.0 0 0 100 2007 902 1650.0 0 0 1650 2008 754 1275.0 0 0 1275 2009 786 1300.0 2 80 1380 2010 709 1276.0 0 0 1276 2011 303 757.0 0 0 757

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2012 450 1125.0 1 30 1155 2013 360 900.0 3 60 960 2014 447 1118 1 0 1118 2015 301 752.5 2 0 753 2016 319 797.5 0 0 798 2017 1047 2618 6 240 2858 2018 167 415 6 225 640 2019 98 240 6 235 475 Total 6801 14619 42 1470 16089

Fig. 3: Deep Tubewell irrigation area potential map (Modified after GWRDP/ GDC 1994).

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Fig. 4: Shallow Tubewell irrigation area potential map (Modified after GWRDP/ GDC 1994).

CONCLUSION The article has reviewed groundwater development ha till 2019 in which STW groundwater irrigated land over the past few years of the Bardiya district. The data is 14,619 ha and DTW groundwater irrigated land is of groundwater irrigation shows that there is a rapid 1,470 ha in the district. Remaining potential land in the growth of groundwater irrigation after 2007. There is district that can be irrigated by groundwater is 23,493 more than 90% of irrigated land developed after 2007 ha. So there is a high potential and challenges for showing there will be more demand and irrigation development of groundwater irrigation in the district land will be developed by groundwater. The maximum but it should be carried out in proper planning and construction activities were carried out in 2016/017 in management of the resource. which irrigated land was developed by 2,826 ha land (Table 1). The total groundwater irrigated land 16,089

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Acknowledgments Kansakar DR (2011) Regulating common pool groundwater under fugitive surface water law: The authors are thankful to the Groundwater limitations in laws and regulations in Nepal irrigation Resources and Development Division, (Unpublished). A report submitted to Jalsrot Vikas Banke for providing data and we are also thankful Sanstha/Global Water Partnership Nepal. to Hydrogeologist Mr Nam Raj Bhattrai for his Mukherjee A, Saha D, Harvey CF, et al (2015) continuous help during data collection and discussion. Groundwater systems of the Indian Sub- Continent. J Hydrol Reg Stud 4:1–14. doi: REFERENCES 10.1016/j.ejrh.2015.03.005 CBS (2012) National population and housing census Sagar Chapagain P (2018) Agriculture Production and 2011 (National Report). Kathmandu: Central Food Security in State Number Five, Nepal. www. Bureau of Statistics. arcjournals.org Int J Res Environ Sci 4:2454– GWRDP/ GDC (1994) Reassessment of groundwater 9444. doi: 10.20431/2454-9444.0401010 development strategy for irrigation in the Terai Shah T Groundwater and human development: (Unpublished). challenges and opportunities in livelihoods and GWRDB/ UNDP (1991) Shallow ground water environment resource of the Terai Bardiya District Mid Western Development Region, Nepal. Technical Report No. 25 (Unpublished).

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