Water allocation optimization in the Orontes River Basin
Georges Comair and Raquel Flinker
Outline
Description of the setting
UN Convention and Factors Associated with Equitable Water Use
Optimization function
Optimal allocation results
The Orontes River Basin
Factors Associated with Equitable Water Use
1. Geography 2. Hydrology 3. Climate 4. Past utilization of the waters 5. Economic and social needs6. Population dependent on the waters 7. Comparative costs of alternative means of satisfying
the economic and social needs of each basin state8. Availability of other water resources9. Degree to which the needs of a basin state may be
satisfied, without causing appreciable harm and substantial injury to a co-basin state.
Factor 1: Geography
Countries Catchment area
(km2)
Lebanon 2,208.73
Syria 16,979.18
Turkey 5,556.56
Total 24,744.48
Turkey22%
Lebanon9%Syria
69%
Factor 2: Hydrology
11%
44%
45%
Contribution to annual discharge
Lebanon Syria Turkey
Factor 3: Climate
Turkey Lebanon Syria
662
560
463
Precipitation
mm
35.3%
23.5%
41.2%
Climate
Syria Lebanon
Factor 4: Existing Utilization
89%
11%
Factor 5: Economic and Social Needs Water demand that meets Economic and social
needs.
Syria does not use its water resources very efficiently
CountriesCurrent Water Demand (million m3)
Lebanon 80
Syria 2,687
Turkey 500
Total 3,26782.2%
2.4%
15.3%
Economic and Social Needs
Syria - FAOLebanon - GovernmentTurkey - Es-timate
Factor 6: Population Dependent on Waters
63.1%36.9%
Population De-pendant on Wa-
tersSyriaLebanonTurkey
CountriesPopulation Dependant on Waters
Lebanon 0
Syria
2,528,000
Turkey
1,480,571
Total
4,008,571
Factor 7: Comparative Costs of Alternatives
CountriesGDP (million US$) World Bank 2010
Lebanon 39,006
Syria 59,147
Turkey 734,364
Total 832,517
7.1%
4.7%
88.2%
Comparative Costs of Alternative
SyriaLebanonTurkey
Factor 8: Availability of Other Resources
Water Stress Index
Syria Turkey Lebanon0
10
20
30
40
50
6054
2620
0
20000
40000
60000
80000
100000
120000
Total water demand in each coun-try
Total re-newable wa-ter re-sources
Factor 9: Appreciable Harm
82.2%
2.4%
15.3%Economic and Social
Needs
SyriaLebanonTurkey
Can be measured by impacts on social, economic and environmental needs.
Class Survey
1. Geography
2. Hydrology
3. Climate
4. Existing utilization
5. Economic and social needs (water demand)
6. Population dependent on waters of the basin
7. Comparative costs of alternative (GDP)
8. Availability of other resources (Water Stress Index)
9. Appreciable harm
Geogr
aphy
Hydro
logy
Rainf
all
Exist
ing
utiliza
tion
Wat
er d
eman
d
Popu
latio
nGDP
WSI
Appr
eciable
harm
0
5
10
15
20
25
6
108 9
15 14
9
15 14
8
15 14
20
1210
8 85
Factor Weights (%)
Class AcademiaExperts
Optimization
Minimize E = 2
Xij is the share of the ith factor for the jth country (%)
Aj is the proportion of the total water that each country should receive (%)
Wi (%) is the weight to be given to each factor taken from the class survey
Existence of Solutions Weierstrass Theorem
Describes conditions on the objective function and the constraint set so that we are guaranteed that solutions will always exist Constraint set is compact (closed and bounded) Objective function is continuous on the constraint set
Optimization results
58%23%
19%
Results - Class
Syria TurkeyLebanon
55%25%
20%
Results – Water Experts
Syria TurkeyLebanon
83%
10%7%
Agreement
Syria TurkeyLebanon
Questions
1. What additional factors do you think should be included in this analysis?
2. Do you agree with the assumptions made for each factor?