Insights in the water-energy-food nexus in the Nile Basin with the new Eastern Nile Water Simulation Model

Transcription

1 Insights in the water-energy-food nexus in the Nile Basin with the new Eastern Nile Water Simulation Model Wil N.M. van der Krogt, Henk J.M. Ogink For International Conference Sustainability in the WaterEnergy-Food Nexus, May 2014, Bonn

2 Eastern Nile characteristics Eastern Nile basin: Nile River basin without the Equatorial Lake basin Nile River length: 6,650 Km EN Basin area : 1,8 million km2 Population : 149 million Located in 4 countries: South Sudan, Ethiopia, Sudan and Egypt Divided into 4 sub-basins: Baro-Akobo-Sobat-White Nile, Abay-Blue Nile, Tekeze-Setit-Atbara and Main Nile Water use: irrigation, DMI, hydropower, navigation, environment Infra-structure: dams, inter-basin transfer, by-pass canals. hydro-power stations

3 Eastern Nile characteristics: discharge Mean Water Discharge 2840 m3/s Main Nile 100% Atbara 13% Blue Nile 55% White Nile 32% According to the report Cooperative Regional Assessment for Watershed Management, Transboundary analysis, Country report, Egypt, July 2006, mean discharge is 2800 m3/s, where 56% is contributed by the Blue Nile, 30% by the White Nile and 14% by the Atbara River.

4 Eastern Nile characteristics: elevation Ethiopia, South Sudan Sudan Egypt Hydro-power potential Irrigation potential

5 Under construction Blue Nile hydro-power potential (Et) Options for the Abay Blue Nile reservoir cascades: Renaissance FSL 640 : under construction Various cascade combinations of Karadobi, Beko Abo Low / High, Lower / Upper Mandaya and Renaissance FSL 640 / 620 dams

6 Why balance: the Water Balancing Act Supply Quantity (Natural Scarcity, Groundwater Depletion) Demand Quality Degradation Cost of Options Population growth Increased welfare Inefficient use Nile 1 januari 2008

7 Nile on short / long term Squeezing the Nile Therefore: A need for a joint understanding of current and future availability and impacts of interventions in the water system on food and energy

8 Eastern Nile Water Simulation Model 1. It has been developed at ENTRO, Addis Ababa, a joint cooperation of the 4 EN countries 2. It has been based on data from the ENTRO library and public domain 3. It is the latest and presently most complete water balance model of the Eastern Nile (EN), covering all users and infrastructure 4. It uses unique hydrological time series with length of 103 years ( ) RIBASIM7 ENTRO library Training at ENTRO

9 1 - Joint development through ENTRO ENTRO the Eastern Nile Technical Regional Office Academics from Ethiopia, Sudan, South Sudan and Egypt Distributed through ENTRO to universities in these four countries: Cairo Univ., Univ. of Khartoum, Addis Ababa Univ. and Univ. of Juba Applied in follow up studies, currently in Atbara Dam Complex Sudan, and Enhanced WRM Study Egypt.

10 2 - Model is public domain (via ENTRO) The model compiles data available from various studies, available in the ENTRO library, and public domain data (internet) The model, including all data, can be requested at ENTRO. site: entro@nilebasin.org The model is built for the generic modeling software RIBASIM (River Basin Simulation Model). The software is free use for education and research purposes and can be requested at Deltares. site: Ribasim.info@deltares.nl

11 3 - Complete Water Balance Model ENWSM covers the catchments of the main EN basins us High Aswan Dam (HAD) incl. Lake Nasser. All current and planned water use and infrastructure, among others: 162 sub-catchments 111 dams: 11 existing and 100 under construction 114 Irrigation areas: 18 existing and 96 potential 3 potential wetland by-passes Lakes, swamps, domestic water use etc. Nile River basin 1 januari 2008

12 3 - Complete Water Balance Model Complete EN network schematization for ENWSM (RIBASIM7) with map

13 4 - Unique hydrological time series: 103 years of monthly flows Avg annual natural flow 86.1 Bcm Aswan recording station (inflow Lake Nasser) 12,500 12,000 11,500 11,000 10,500 10,000 9,500 9,000 8,500 8,000 7,500 7,000 6,500 6,000 5,500 5,000 4,500 4,000 3,500 3,000 2,500 2,000 1,500 1, /29/ /27/ /25/ /23/ /21/ /19/ /17/1955 Simulated flow (m3/s) 12/15/ /13/ /11/ /9/ /7/1995 Monitored flow (m3/s) Malakal recording station 2,400 2,300 2,200 2,100 2,000 1,900 1,800 1,700 1,600 1,500 1,400 1,300 1,200 1,100 1, /29/ /27/ /25/ /23/ /21/ /19/ /17/1955 Simulated flow (m3/s) 12/15/ /13/ /11/ /9/ /7/1995 Monitored flow (m3/s) Verification case: Nile natural flow, no structures and no users, check recorded and simulated river flows at the 42 recording stations ( ) 1 januari 2008

14 3 - Illustrations of W-E-F impacts of interventions Construction of new Atbara Dams Complex (Rumela-Burdana dams) Development of new Kenana irr. Construction of new Beles dam and Dinder and Beles irr and connection with Lake Tana Various combinations of new Renaissance dam with Beko Abo, Mendaya and Karadobi hydro-power dams Heightening of existing Roseires dam Construction of new Renaissance dam 1 januari 2008 Others: alternative crop plan climate change

15 Simulation cases in the illustrative analysis Case Combination of measures S000 No management actions. Base line, current condition. S001 Renaissance640 Beles dam + Dinder and Beles irr. (Et) High Roseires + Kenana irr. (Su) S002 Abbay dams cascade A of Karadobi + Beko Abo Low + Mandaya + Renaissance620. Beles dam + Dinder and Beles irr. (Et) High Roseires + Kenana irr. (Su) S003 Abbay dams cascade B of Karadobi - Beko Abo Low - Madaya Upper - Renaissance dam640 Beles dam + Dinder and Beles irr. (Et) High Roseires + Kenana irr. (Su) S004 Abbay dams cascade C of Beko Abo High (1062) + Mandaya + Renaissance620 Beles dam + Dinder and Beles irr. (Et) High Roseires + Kenana irr. (Su) S005 Abbay dams cascade D of Beko Abo High (1062) + Mandaya Upper + Renaissance640 Beles dam + Dinder and Beles irr. (Et) High Roseires + Kenana irr. (Su) S006= S001+alt. crop plan, S007= S001+Climate change

16 Border ET-Su Results: change in flow regime Compared to present (S000): Monthly flow variation flattened out almost completely: beneficial for Sudan irrigation Inflow to Lake Nasser reduces by about 9-11% Sediment inflow to Roseires reduced 1 januari 2008

17 Results: change in Lake Nasser water level Jan Feb Mar Apr May S000 Jun Jul S001 Aug S007 Sep Oct Nov Dec Lake Nasser water level Compared to present (S000): Average monthly level of Lake Nasser reduces, Toshka spilling reduces, Lake Nasser open water evaporation losses reduces by 31% (S001), Toshka pumping energy consumption increases by 26% (S001)

18 Results energy: change in production Total energy production (GWh) per country Compared to present (S000): Overall energy production increases by % Energy production in Sudan increases by 14-18% Power production at Aswan reduces by 13-15%

19 Results water : change in open water evaporation Average annual open water evaporation (Mcm) from reservoirs Compared to present (S000): Lake Nasser open water evaporation losses reduces, Open water evaporation in Sudan and Ethiopia increases Overall open water evaporation the same (S001) and slight increase cascade cases (S002-5) 1 januari 2008

20 Results food: Irr and DMI water use Total water use for irr. and pws per country (Mcm) Total water use per country S000 S001 S002 Ethiopia S003 Sudan S004 Egypt S005 S006 S007 South Sudan Water use of Sudan (Mcm) Sudan water use S000 S001 S002 S003 S004 S005 Evap. from reservoirs 1 januari 2008Irr. and pws use S006 S007

21 Example follow-up use of ENWSM Atbara Dam Complex sedimentation and operation study Atbara Atbara Setit Atbara Tekeze

22 Conclusions The ENWSM can be used to explore W-E-F interaction in Ethiopia, Sudan, South-Sudan and Egypt for various scenarios and interventions Illustrations show that new dams in Ethiopia benefit Ethiopia s power production but as well increases the benefits of Sudan s irrigation water use from the regulated flow. Strong points of the model are the unique hydrology (103 years) and the completeness of infrastructure and water use Additionally, the joint development by experts from the basin countries at ENTRO and the public availability of the model (via ENTRO) has contributed to making the model a shared reference for future analysis, as is already the case for Egypt and Sudan (Atbara dams complex study)

23 Thanks Grand Ethiopian Renaissance Dam 1 januari