Prof. Medhat Aziz Director, NRI, MWRI,EGYPT Eng. Tahani Sileet General Director, Nile Water Sector, MWRI,EGYPT

Transcription

1 NILE RIVER FLOOD PROTECTION Prf. Medhat Aziz Directr, NRI, MWRI,EGYPT Eng. Tahani Sileet General Directr, Nile Water Sectr, MWRI,EGYPT

2 Main Features f the Nile River Basin area : abut 3.0 millin square km. Area f lakes is 81,500 square km. Area f swamps is 70,000 square km. Length : 6700 km. Length f Rivers and Tributaries is 37,500 km. Average annual rainfall 1661 BCM Average annual yield at Aswan 84 BCM 11 Riparian States with 370 millin peple

3 Nile River Fld Classificatin Highest recrded fld fr the natural river at Aswan :150 BCM( ) Lwest recrded value: 42 BCM( ). Nile River natural flw recrds at Aswan can be divided int 5 categries: 1-Very lw fld (52, r less, BCM). 2-Lw fld (70 BCM). 3-Average fld (92 BCM). 4-High fld (110 BCM). 5-Very high fld (exceeding 110 billin BCM).

4 Key Issues in Fld Management Lack f gd quality hydrlgical (flw) data Establishing and perating real time gauging statins Data Cmmunicatin system & data sharing between agencies & cuntries Lack f capacity t predict shrt perid rainfall data Institutin and Staff capacity building in fld frecasting & hydrlgical mdels Sustainability f fld frecasting systems Very shrt lead time

5 Reginal Backgrund Sudan The annual fld frm the Blue Nile replenishes sil misture and fertility, and recharges grundwater, s is the mainstay f agriculture Hundreds f villages,because f their prximity t the river banks are adversely affected in years f abve average flds. Egypt HAD was cmpleted in 1970, and generatin f hydrpwer and regulatin f water fr irrigatin became a mainstay f the Egyptian ecnmy. Strage filled ver abut 10 years, and releases were stable until Ethipia severe drughts in the 1980s, where the lake levels declined prgressively High fld years in 1998 t 2001 prved that fld risk management is still n the agenda fr the gvernment f Egypt.

6 Sinai Flash Flds Flash flds n and after 18 January 2010 left 780 hmes ttally destryed, 1,076 submerged and the area suffered material lsses f ver US$25.3 millin. The flds ruined 59km f rads, killed 1,838 animals and felled 27,820 (mstly live) trees.

7

8 August Khartum, Sudan Pht: IFRC

9 Examples f fld Damage Impact f Flash Flds as f 11 August 2014 in Sudan Surce IRCS. (IFRC)

10 Measures Undertaken High fld risk: Egypt Nile River bank prtectin (abut 200 km alng the River Nile were prtected by stne revetment). Hydraulic structure prtectin Preventin f Nile encrachments t allw fr the river maximum discharge capacity. Lw fld risk: Prviding water requirements fr agricultural lands Slving navigatin prblems Sudan Sme riparian villages have develped systems f lw levees (terraces). Mre frmal levees exist in certain urban areas (Khartum, Dngla).

11 Fld Frecasting Egypt Nile Water Sectr: watershed rainfall mnitring using rainfall satellite images, which give an indicatin fr the cming fld fr abut ten days in advance. the sectr mnitrs the fld water levels and discharges alng Nile Basin gauging statins. Planning Sectr: mnitrs, thrugh fld frecasting and simulatin center, the climatic changes and Nile Basin rainfall indicatins. It uses the satellite images and hydrlgical mdels. HAD Authrity : Uses the previus flw recrds and cmpare it with the cming fld recrds using the least square methd t develp a linear relatinship between incming flw frm the beginning f August t the end f June and the frecasting fld perid. The authrity uses the previus Nile Basin fld recrds t get an apprximatin fr the cming fld. Fr shrt perids, the cming flw recrds are used t have an indicatin fr the cming 15 days. Nile Research Institute: uses the statistical frecasting appraches perfrming histrical recrd analysis t prpse and utline the target flw. It can prvide the frecasting fr ne r mre cming year/s.

12 Billin Cubic Meter Fld Fecasting / / / / / / / / / / / / / /14 Egypt Day 250 Billin Cubic Meter Day 2013/14 Average frm 2001/02 t 2012/13 Billin Cubic Meter April May June July Aug Sep Oct Nv Average 2013/2014 Dec Jan Feb March Data : Rainfall Satellite Images RFE (8km) 3prducts: Accumulated rainfall fr studied year cmpared with : accumulated f the pervius years, average accumulated rainfall fr the pervius years and Every 10 days fr studied year cmpared with average fr each 10 days fr pervius years.

13 Nile Frecast Center established in 1992 t prvide a real-time hydrmeterlgical frecasting system fr the Nile River Basin. Capabilities: - Mnitr hydr meterlgical cnditins in the Blue Nile and Atbara Basins; - Data management and prcessing; - Analyze utputs frm different frecasting tls - Prduce and distribute regular Nile Frecast Center Bulletin - Set different alternatives and scenaris fr Nile WRM

14 Fld Frecasting Sudan Fllwing the flds f 1988, the Sudanese Ministry f Irrigatin and Water Resurces initiated the establishing f an peratinal fld frecasting system, develped with the Netherland technical assistance and became peratinal in 1992, knwn as FEWS Sudan. This system was updated in cllabratin with ENTRO with the mdern standards f the current Delft FEWS frecasting platfrm using data prvided frm Different surces : Rainfall estimates(usgs, TRMM and CMORPH) and water level frm Hydrlgical statins.

15 Fld Frecasting Sudan The frecasting mdel is cmbined frm three mdels: HEC-HMS rainfall runff mdel f the upper blue Nile catchement (upstream f the brder at Eddeim gauging statin). HEC-RAS mdel f the Blue Nile between Eddeim and Khartum Linear crrelatin Mdels between key gauges in the Blue and Main Nile between Eddeim and Dngla. Majr utput f the Sudan FEWS : Estimated rainfall gridded maps and weighed rainfall hyetgraphs Simulated flw hydrgraph at Eddeim (upper Blue Nile watershed utlet) using HEC-HMS hydrlgical mdel based n satellite rainfall estimates. Updated frecast flw hydrgraph at Eddeim based n the bserved flw series during the histrical perid. Simulated and updated frecast f flw and water level hydrgraphs at Blue Nile Hydr statins: Rseires, Singa, Sennar, Medani, Kamlin, and Khartum. Fld seasn cmparisns fr the bserved 2014 fld water level hydrgraph with the histrical water level hydrgraphs and seasnal mean. Linear crrelatin water level frecast at Blue and main Nile frm Eddeim t Dngla.

16