4/3/2017. Water Accounting and Auditing for Irrigation and Drainage Systems. Changes in irrigation and drainage sector

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1 Water Accounting and Auditing for Irrigation and Drainage Systems Wim Bastiaanssen With inputs from Gonzalo Espinoza Jonna van Opstal Tim Hessels Changes in irrigation and drainage sector We are facing a wide range of changes in the I&D sector: Population growth from 3.0 billion in 1960 to about 7.4 billion now to 9.7 billion in 2050 and 11.2 billion in Climate change Localized, generally negative, impacts Growing water scarcity Worldwide, more acute in arid zones Changing water use priorities Pressure on agriculture to release water for domestic and industrial use Societal Rural to urban drift Economic Rising standards of living Education Better educated rural populations Attitudes & expectations Changing attitudes to government; changing expectations for rural youth Agricultural labor Increasing role of women Connectivity Mobile phones, computers, internet New technologies available Remote sensing, GIS, MIS, SCADA, etc. Source: Joop Stoutjesdijk & Martin Burton, WaterWeek 15 March

2 Increased management effort We must quantify and manage the irrigation water balance Source: Joop Stoutjesdijk & Martin Burton, WaterWeek 15 March

3 How much water is available for irrigation every month? Water Accounting Plus (WA+) The need for an independent water accounting system 3

4 WA+ provides information on. How do we acquire (global standard) data? Consumptive use vs. Non-consumptive use Beneficial vs. Non-beneficial use Utilized vs. Utilizable flows Green vs. Blue water flows Surface vs. Groundwater abstractions Monthly storage mechanisms Agricultural, economic, ecosystem services Water productivity Sustainability, resilience Reuse and recycling of water in basins and atmosphere Water scarcity, water security etc Unlocking Reduce bureaucracy 4

5 Remote Sensing Global Hydrological models Open Access data used in WA+ RS data directly downloadable More modelling needed (indirectly available) GIS data Hydrological data Ground measurements Sheets Tables Maps Land Use Land Cover (LULC) - GlobCover Actual Transpiration (T) Protected areas (A) Ratio Fast/Slow runoff Precipitation (P) - CHIRPS Actual soil Evaporation (E ) Bathemetry Surface runoff Actual EvapoTranspiration (ET) - ETEns ET green water consumption (ET_green) Weather data (meteo) Baseflow Soil moisture (SM) - ASCAT ET blue water consumption (ET_blue) Terrain elevation (DEM) Storage changes Surface temperature (LST) - MODIS Water withdrawals (Q) Soil physical data Outflow from basins Surface albedo (alpha) - MODIS Beneficial / non-beneficial water Ratio SW/GW Population density consumption withdrawals Water levels (l) - Jason Reference EvapoTranspiration (ET0) Livestock density Lateral groundwater flow Change in gravity (delta S) - GRACE Interception (I) Grey water consumption Groundwater recharge Snow cover (cl) - MSG Soil erosion (Ero) Environmental flow requirements Cloud cover (sn) - MODIS Dry matter production (Bio) Depth of root zone Leaf Area Index (LAI) - MODIS Crop yield (Y) Vegetation Cover (Vc) - MODIS Crop Yield due to rainfall (Y_P) Net Primary Production (NPP) - MODIS Crop yield due to irrigation (Y_IRR) Total Dissolved Solids Crop water productivity (WP) Chlorophyll Water productivity due to rainfall (WP_P) Water body area Water productivity due to irrigation (WP_IRR) Carbon sequestration (C ) Lifestock feed production (LiveS) Fuelwood production (Fuel) 5

6 Operational flow measurements remain to be a challenge What is the ACTUAL irrigation water distribution? 6

7 Rootzone soil moisure variability November 2016 (Bekaa Valley) Irrigation Applications - Incomati Basin South Africa (30 m x 30 m) cm3/cm3 Agriculture, Ecosystems and Environment, Van Eekelen et al.,

8 Efficiency, productivity and reuse Food production = Efficiency Consumptive use = Water Productivity Withdrawal Return flow = Reuse 8

9 Reliable data on ET and biomass production (Imperial Valley) Example land and water productity in rice (Vietnam) at 30 m x 30 m 2500 Cumulative Evapotranspiration (kaf) Oct- 97 Nov- 97 Dec- 97 Jan- 98 Feb- 98 Mar- 98 Apr- 98 May- 98 Jun- 98 Jul- 98 Aug- Sep Water Balance SEBAL

10 WaterPix for irrigation & drainage P ET Data input for WaterPix Qsw Vertical water balance Pixel-based Yearly basis Remote sensing based Monthly estimates ΔSsm Qgw Percolation and drainage Remote sensing Precipitation Evapotranspiration Soil moisture - Saturated water content Leaf Area Index Root depth variable lat 12 i=1 12 P i ET i ΔSi sm = i=1 Qi sw + Qi gw time lon 10

11 Runoff & Drainage Jordan River, January 2008 WA+ estimates local river flow 0 m3/s 17.4 m3/s Mean = 64mm Mean = 52mm Mean = 12mm 11

12 Water levels and volumes from altimeters RS- based water level estimates Lake Tana (Ethiopia) R 2 = 0.95; RMSE = 16.2 cm R 2 = 0.96; RMSE = 11.5 cm Water level results Surface areas Water volumes R 2 = 0.95; RMSE = 13.3 cm R 2 = 0.97; RMSE = 10.5 cm 12

13 Assessing groundwater abstractions Middle East 13

14 Annual net groundwater abstraction Azraq (Jordan) GRACE-Derived Groundwater Depletion in NW India a) Averaged groundwater depletion in northwest India b) Significant mass decrease in northwest India is captured by GRACE, and is attributed to groundwater depletion. Chen et al

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16 Water Auditing Partnership for Water Accounting 16

17 Do you want to know more about Water Accounting Plus? My dream.. We have a restyled website: 17

18 Thank you! 18