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Sustainability of Groundwater Use for Irrigation in Northwest Region of Bangladesh

Sustainability of Groundwater Use for Irrigation in Northwest Region of Bangladesh. Workshop on Research to Inform Food and Nutrition Security Policies 3-4 July, Ball Room, Rupashi Bangla Hotel, Dhaka. Challenges. 2 º C. Withdrawal of GW.

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Sustainability of Groundwater Use for Irrigation in Northwest Region of Bangladesh

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  1. Sustainability of Groundwater Use for Irrigation in Northwest Region of Bangladesh Workshop on Research to Inform Food and Nutrition Security Policies 3-4 July, Ball Room, RupashiBangla Hotel, Dhaka

  2. Challenges 2ºC Withdrawal of GW • Sustainability of GW use is becoming a vital concern in many countries of the world, Bangladesh in particular, mainly NW of Bangladesh-where GW declines 5-10m in the dry period • WB‘s concern is that expected 2°C rise in world’s aver Temp in next decades and shifting of rain patterns could leave some areas under water & otherswithout enough water for irrigation or drinking which threatening food production, livelihoods & reduction on poverty in South Asian Countries. June 19, 2013 • Contribution of GW use for irrigation has increased 2.5 times over 20 years • Below-average rainfall, higher temp • causing drought, increased ET, delayed • monsoon, dry up of surface water bodies & thus • lowering of GWT leading water crisis are some • barriers to ensure sustainability in the NW Bangladesh.

  3. Challenges (contd.) • Irrigation cost has increased many folds which threatens the economic viability of future crop production. • Irrigation cost in Bangladesh = > 4times higher than India, 6 times than Thailand and Vietnam. This is mainly because of dependence on GW irrigation • Defects in present IWM practices has been identified. If water is managed properly, BGD can save addl. amount ≈ 1/6 of the total BGD • Budget for FY 2003-4 (USD 8,962 million) (Dey • et al., 2006), and also similar to the ADP budget • of Bangladesh for FY 2009-10 (USD 4072 • million). www.iwaponline.com/wp/00806

  4. Objectives • Assess trends in groundwater table and 10 major crops for the past 30 years. • Financial and economic profitability of different crops along with likely changes over time due to declining GW tables. • Estimate cost of excess water lifted for irrigation. • Recommend policies for sustainable use of irrigation water in northwestern Bangladesh. For assessing sustainability of GW use for irrigation, three objectives based on ToR and one more have been selected

  5. Methodology Sustainability Indicators Environmental Sustainability Social Economic • Social • % of people practicing GW recharge methods • % of people using alternative sources of water for irrigation or other purposes • Peoples’ perception in water management • Environmental • River water contrib. to GW • Precipitation • Groundwater table • Groundwater withdrawals • Well intensity • Excess water • Ten major crops and areas • Wetland area • Change in crop type • GW contamination • Conservation for ASGUI, we have selected 16 indicators belong to E, E, S issues • Economic • Cost of GW use for irrigation • Financial Profitability • Economic profitability

  6. Study Area • Rajshahi • Pabna • Bogra • Rangpur • Dinajpur } Northwest Bangladesh Geographically, the study area extends 230 48’ 14.3’’ to 260 03’ 16.8’’ latitudes and 880 18’ 44.99’’ to 890 43’ 50.71’’ longitudes.

  7. Data We have used both P& S data Data for ET estimation Location: Five Upazilas from five districts in NW region. RS Data: MODIS satellite images & Landsat 7 ETM+ were used in this study. Field coordinates of 131 Boro rice fields located in the selected 5-upazilas were collected using hand held GPS.

  8. Data analysis • Software • SPSS 16.0 and MS Excel • ILWIS 3.4 and Arc GIS 9.2 software for image processing and analysis • Arc GIS 10 - used for mapping. • Financial profitability analysis of major crops : • Formula used ∏ = P1Q1 + P2Q2 - ∑PiXi – TFC • Economic profitability/comparative advantage of major crops: • Border price measured at Farm gate (Import Parity) : Pj = Pjb + Cjm – Cjd • Border price measured at Farm gate (Export Parity): Pi = Pib E0-Ci • Nominal protection (NPC) expressed as: NPCi = Pid/Pib • Effective protection

  9. Comparative advantage of crop production Domestic resource cost (DRC) Estimation of ET Forecasting of irrigation cost Autoregressive Integrated Moving Average or ARIMA (p,d,q) models used. An AR(p) model has the form: Yt = a1Yt-1 + … + apYt-p + et SEBAL and FAOPenman-Moneith : Where, Go – Soil heat flux, W.m-2 H – Sensible heat flux, W.m-2 λE – Latent heat flux, W.m-2 associated with ET; Rn- Net radiation FAO Penman-Monteith method Figure : Components of the Energy Balance

  10. Normalized Differentiate Vegetation Index (NDVI) Map ET + + Estimation of Excess Water Precipitation Excess Water GoB-BRAC weather station for climatic data Vegetation indices over NW region

  11. Results Groundwater table • Declining trend of GWT overtime y = -0.014x - 4.218 R² = 0.313 7”/y Fig . Changes in depth of GWT depth (Jan-May) over time. Fig . Map of depleted upazilas in five districts

  12. Why GWT declines? Fig. Increase of irrigated area over time Fig. Increase of TW over time • DTW became almost double • STW reached more than five time higher • TW increased 8.5 times where irrigated land increased 1.6 times. • TW intensity: 6.9 to 36 nos/ km2 Fig. Intensity of TW

  13. River water level • RWL (Yearly avr.) • 20.1m • 18.3 m Fig. Northwest region river water level fluctuation (yearly avg.) River water discharge • RWD (Yearly avr.) • 90.8 • 56.9m3/sec Fig. Changes in river water level (a- maximum, and b-minimum) GW & SW appeared to be distinct sources of water, basically they are one singular source of water connected in the hydrological cycle. Fig. Relationship between RWL & GWT

  14. Change in Wetland area in selected Districts About 1/3 of the wetlands in NW region has been lost over 21 yrs. Declining trend of annual rainfall (mm)

  15. Changes in crop areas Sudden increase of B A during 1980/81- 2000/01 & Marginal 2000/01- 2010/11. Sudden increase of BA is likely liberalization of govt policy (1979) on procurement, installation and distribution, and management of irrigation equipment & thus farmers installed huge nos. TW indiscriminately for getting higher production owing to achieve food security Figure Change in crop area over time at Boro area highest in Rangpur followed by Rajshahi, Dinajpur, Bogra and Pabna districts

  16. Increase of Boro area over time B=17A 2010/11 Area, ha A 1980/81 Boroarea Why farmers produce boro? 1. Most of farmers are marginal and small group and they have peace of land to meet their principal food - Rice demand, they produce rice. Second one is likely, if a farmer’s field is within the coverage of irrigation scheme, he has physical benefit of rice cultivation due to intrusion of IW in his plot and thus refrain the farmer to opt for other crops

  17. NDVI ET of boro rice 21 January 11 April ET 11 April 21 January ET estimated by SEBAL and Penman-Monteith methods.

  18. Excess water extracted Fig. NW region Irrigation water requirement and extraction Fig. Water requirement & Excess water lifted Amount extracted was highest in Badarganj of Rangpur district followed by Godagari of Rajshahi, Birampur of Dinajpur, Chatmohor of Pabna district, and least in Dhupchancia of Bogra district Fig. Cost of excess water

  19. Financial Profitability of Five Major Rabi Season Crops Highest GR found for Potato followed by boro, lentil, wheat, mustard Highest NR for Lentil followed by potato, wheat, boro and mustard Figure: Cost and return of different crops cultivation Figure: Farm Category wise Benefit Cost Ratio of Boro Rice

  20. Economic Profitability Table : Domestic resource costs (DRC) for selected agricultural commodities DRC<1 Comparative advantage, we can think for import substitute DRC>1 not efficient for export

  21. Major Cropping Patterns and suggested crops in the study area

  22. Actual and projected irrigation cost (Tk/ha) Simulation of time path of boro rice production cost and GWT depth 1

  23. Using forecasted irrigation cost (other costs reaming same) the financial and economic analysis of boro rice Considering FIS, after 20 yrs, TPC will be increased to 1.5 times & Net return will be 1.5 less than now. In case of economic Prof. DRC is increasing if it reaches to >1 then production of boro will be comparatively disadvantage

  24. Status of sustainability of GW use for Irrigation in NW Bangladesh √ Satisfied Not Satisfied To ensure sus, what are the statuses of study findings

  25. Environmental Impact 12464.8T (2010) OC N S K Zn 3895 T (‘73-90) P Nutrient mining Pesticide use Drought Polluted water percolation

  26. Socio-economic impact Nutrition deficiency Jobless Time and Energy loss for collecting water Economic loss from pisciculture - drought Health problems

  27. If water is not managed properly, Days are coming when - possibilities of

  28. Conclusion

  29. Recommendations 4. Local planners should consider recharge areas when planning land use that could reduce recharge or pose a risk to GW quality. 5. Strengthen appropriate monitoring organizations for tracking GW recharge, surface and GW use & improvement in surface and GW quality. 6. Regional cooperation can guarantee a sustained future in terms of water availability since the basin areas of the river systems is dissected by international boundaries. 7. Water User Association rooted strong small holder irrigation community should be given statutory powers to fix rate determined by WRAs/BADC/BMDA. 1. Encourage HYV crop rather than boro. Emphasis should be given on lentil in Pabna district and wheat (except Bogra), mustard and potato (except Rajshahi and Pabna) in other four districts because return is higher in these crops. Production of potato & lentil would be highly efficient for import substitution. 2. An estimated water budget should be prepared that includes recharge, extraction & change in storage in the aquifer(s). 3. Managed Aquifer Recharge should be undertaken as a national programme & strategy considering different regional contexts by adopting a series of activities like harvesting of surface & rain water & their storage & conservation through excavation of existing canals, ponds, khals, & water bodies in massive scale.

  30. 8. Irrigation water price should be determined as a rule on volumetric basis in order to meet equity, efficiency and economic principles. WUA should fix the rate of irrigation cost from private TW which is much higher than public TWs. 9. Optimization of command area of each DTW and STW though consultation with Water User Association where electric connection to pumps is key component for regulation on GW use & to be realized phase-wise i.e., with short-term, medium-term and long-term planning. 10. Modern water management technology like alternate wetting and drying (AWD), water saving technology like hose pipe irrigation, drip irrigation, climate change adaptive technology such as drought tolerant crop variety, etc. would bear no value without carrying out irrigation volumetrically.   Policy recommendations (contd.) 11. Awareness, campaign and advocacy on sustainable water management concepts, principles and methods. Department of Agriculture Extension can take a lead for this action. 12. Plan of Action in line with basic policies namely NAP 2010, NFP 2006, CIP 2011, NWP 1999, NAPA 2009, NSDS 2008, BCCSAP 2009 etc. might be formulated under existing BADC or BMDA or proposed GD or WRA on short-term, medium-term and long-term basis.

  31. Thank you

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