optimisation for sustainable water resources management · optima, d09.2 elard 1...

OPTIMA, D09.2 ELARD

1

INCO-CT-2004-509091

OPTIMA

Optimisation for Sustainable Water Resources Management Instrument type: Specific targeted research or innovation project Priority name: SP1-10

D09.2 Lower Litani Basin Case Study Due date: 30/04/07 Actual submission date: 25/05/07 Start date of project: 01/07/2004 Duration: 36 months Lead contractor of deliverable: ELARD Revision: vs 1

Project co-funded by the European Commission within the Sixth Framework Programme (2002-2006) Dissemination level PU Public X PP Restricted to other programme participants (including the Commission Services) RE Restricted to a group specified by the consortium (including the Commission

Services)

CO Confidential, only for members of the consortium (including the Commission Services)

OPTIMA, D09.2 ELARD

1

Executive Summary This report presents the results of the water resources optimization conducted for the Lower Litani River Basin as part of the project entitled “Optimisation for Sustainable Water Resources Management” (OPTIMA), an EU sponsored three-year regional research project, which started on July 1st 2004, and is implemented in Lebanon by Earth Link and Advanced Resources Development (ELARD) s.a.r.l and the National Center for Remote Sensing (NCRS). The overall aim of the project is to develop, test, and critically evaluate an innovative approach to water resources management in the Mediterranean region. The Litani River is the longest and largest river in Lebanon. With a length of 170 kilometers, it originates from al oleic springs in Hosh Brada in the Bekaa Valley and flow southward, and discharges into the Mediterranean Sea, 7 km north of Tyre, an ancient Phoenician city. The characteristics of the Litani Lower basin were input in a topology model using a Water Resource Model (WRM), which is used to assess the efficiency of the baseline model scenario. The involvement of the various stakeholders and their contribution allowed the identification of the main key issues and constraints for the optimization process for the different scenarios of the Litani Lower Basin. Different optimization scenarios were tested including instruments and constraints and a set of feasible solutions were derived. The report summarizes the main findings of the optimization runs. This report is sub-divided in 3 distinct sections. Section 2 presents a summary of the baseline scenario. Section 3 presents the optimization scenario and discusses the optimization results. Section 4 presents the next steps.

OPTIMA, D09.2 ELARD

2

Table of Contents Executive Summary .....................................................................................................1 Table of Contents.........................................................................................................2 List of Figures...............................................................................................................3 List of Tables................................................................................................................4 1. The Baseline Scenario..........................................................................................5

1.1. Baseline Topology Model .............................................................................5 1.2. Economical analysis.....................................................................................8 1.3. Objectives and constraints in the Lower Litani Basin ...................................9

1.3.1. Strengths and weaknesses ..................................................................9 1.3.2. Threats and opportunities...................................................................10 1.2.3. Objectives and Constraints.................................................................11

2. Optimization Scenarios and Results ...................................................................13 2.1. Scenario 1: Infrastructure based ................................................................13

2.1.1. Additional Infrastructure......................................................................13 2.1.1.1. Prospective KFAR SIR DAM..............................................................13 2.1.1.2. Prospective Khardale Dam.................................................................14 2.1.1.3. Deir Mimess waste water treatment plant ..........................................14

2.1.2. Maintained infrastructures ..................................................................14 2.1.2.1. Qasmiyye Canal .................................................................................14 2.1.2.2. Taibe Domestic Station ......................................................................15 2.1.2.3. Touristic resorts..................................................................................15

2.2. Scenario 2: Demand Change Scenario ......................................................15 2.3. WRM Results of New Scenarios ................................................................15

2.3.1. Results of Infrastructure scenario (water ware model) .......................16 2.4. Optimization Scenario ................................................................................17

2.4.1. Topology and Instruments ..................................................................17 2.4.2. Objectives and Constraints in the Optimization Scenario...................19

2.4.2.1. Objectives...........................................................................................19 2.4.2.2. Constraints .........................................................................................20

2.5. Optimization Results ..................................................................................20 3. Further Steps ......................................................................................................25

OPTIMA, D09.2 ELARD

3

List of Figures Figure Page

Figure 1. The topology water resource model baseline scenario................................5 Figure 2. Zone of the kfar Sir dam .............................................................................13 Figure 3. Zone of the Khardale dam .........................................................................14 Figure 4. Litani Lower basin Topology model used in the Optimization runs.............17 Figure 5. Frequency distribution for water cost criteria of the 82 retained alternatives computed in the optimization .....................................................................................22 Figure 6. Frequency Distribution for the Benefit/Cost criteria for the retained 82 alternatives.................................................................................................................22 Figure 7. Frequency Distribution for the Supply/demand criteria for the retained 82 alternatives.................................................................................................................23 Figure 8. Frequency Distribution for the Total shortfall criteria for the retained 82 alternatives.................................................................................................................23 Figure 9. Frequency Distribution for the Total unallocated criteria for the retained 82 alternatives.................................................................................................................23

OPTIMA, D09.2 ELARD

4

List of Tables Table Page

Table 1. List of the various nodes forming the topology model of the Lower Litani basin.............................................................................................................................6 Table 2 . Calculation of the unit cost (Euros/m³) of water for the irrigation from the Qasmiyyeh Canal.........................................................................................................8 Table 3. The various parameters input in the water resource model for the calculation of cost/benefit ratio for the various demand nodes existing on the Litani Lower portion.....................................................................................................................................9 Table 4. Main elements of strengths and weaknesses of the Lower Litani Basin according to the results of the first working session...................................................10 Table 5. List of opportunities and threats for the Lower Litani Basin .........................10 Table 6. Advantages of the economical instruments and their role in meeting the set objectives ...................................................................................................................12 Table 7. Summary of WRM Results of the New Scenarios......................................16 Table 8. Type of nodes and associated infrastructures/methods in the list of instruments.................................................................................................................18 Table 9. Percentage of application of the instruments used in optimization run ........21 Table 10. List of constraints applied in the optimization model.................................21 Table 11. Retained potential scenarios based on the set of constraints, economical analysis, and potential combination of instruments....................................................24

OPTIMA, D09.2 ELARD

5

1. The Baseline Scenario

1.1. Baseline Topology Model The characteristics of the Litani Lower Basin were input in a topology model using a Water Resource Model (WRM), which allows translating the real model into a baseline model. The major points of water discharge, recharge, diversion, demand, and control on the River were input into different types of nodes to form a baseline Water Resources Model (WRM) for the Litani Lower Basin. The collected data during field visit and literature review, allowed drawing a baseline scenario. This baseline scenario was updated following the first participatory workshop. The model topology is shown in Figure 1. Table 1 presents a list of the various nodes considered in the baseline scenario.

Figure 1. The topology water resource model baseline scenario

OPTIMA, D09.2 ELARD

6

Table 1. List of the various nodes forming the topology model of the Lower Litani basin

Type of Node X Y Name Description

1 confluence -93

275 Quasmieh canal C Point of Return flow from Qasmiyye Demand (0)

2 confluence -64

275 Ain kouroum C Point of Flow Discharge from Ain El Kouroum Sub

3 confluence -61

275 Tair falsay C Point of Flow Discharge from Arzoun Sub

4 confluence -45

275 Ain Zarqoun C Point of Flow Discharge from Ain Zarqoun Sub

5 confluence -39

275 Ouadi Arzoun C Point of Flow Discharge from Arzoun Sub to Tair Felsay

6 confluence -32

275 Ain Srifa C Point of Flow Discharge from Srifa Sub to Chehour

7 confluence -

28 275 Boustane Habba C Point of Flow Discharge from

Ain Sinai Sub to Mazraat Tair Semhat

8 confluence -24

275 Quakiyit el jeser C Point of Return flow from Quakiyit El Jeser Demand

9 confluence -14

275 Ez Zaidanieh C Point of Flow Discharge from Ain El Basatine Sub

10 confluence -8 275 Chaqra C Point of Flow Discharge from Chaqra Main Sub

11 confluence 0 275 Taibe C Point of Flow Discharge from Taibe Pumping Station

12 confluence 9 255 Tour C Point of Return flow from Tour Demand

13 confluence 9 225 Qlaiaa C Point of Return flow from deir Mimess

14 confluence 9 190 Khardale C Point of Return flow from Khardale Demand

15 confluence 15 263 Disharge deir mimes C

Point of Flow Discharge from deir Mimess Waste water Plant

16 confluence -84

275 Ain En Nemra C Point of Flow Discharge from Ain Nemra Sub

17 confluence -80

275 Ain Bedias C Point of Flow Discharge from Ain Bedias Sub

18 confluence -50

275 Ain Azahi C Point of Flow Discharge from Ain Azahi Sub

19 confluence 13 280 Ouadi el Azhaqani C

Point of Flow Discharge from Ouadi Azhaqani Sub

20 control -17 275 Ghandouriyyeh

Control Water Level Monitoring Station in Ghandouriyyeh Area

21 control 9 205 Khardale Control Water Level Monitoring Station in Khardale Area

22 control 20 -5 Qelia Control Water Level Monitoring Station in Qelia Area (start)

23 control -95 275 Qasmiyye Control Water Level Monitoring Station

in Qasmiyyeh Area (end)

24 demand 2 240 Tour De Touristic resorts / domestic water demand / 4" pump directly on the River

25 demand -55 250 Teir Falsay De

Touristic resorts / domestic water demand / 4" pump directly on the River

26 demand 5 300 Taibe Domestic Station De

Domestic Water Pumping Station for Taibe village (approximately 6000 Capita)

OPTIMA, D09.2 ELARD

7


27 demand -88 -10 Qasmiyye Canal De Banana and citrus lands (total of

3220ha)

28 demand -20 250 Qayqaiet el Jeser

De

Touristic resorts / domestic water demand / 4" pump directly on the River

29 demand 2 175 Khardale De Touristic resorts / domestic water demand / 4" pump directly on the River

30 diversion,single 9 240 Tair Felsay Di Divert a total of 0.24 Mm3/ year of water for Tour touristic resort

31 diversion,single 9 175 Khardale Di Divert a total of 0.24 Mm3/ year of water for Khardale touristic resort

32 diversion,single -20 275 Quakyit el Jeser Div

Divert a total of 0.24 Mm3/ year of water for Qayqaiet touristic resort

33 diversion,single -55 275 Tour Di

Divert a total of 0.24 Mm3/ year of water for Tair Falsay touristic resort

34 diversion,single 5 275 Taibe Di Divert a total of 18000 m3/day of water for Taibe touristic resort

35 diversion,single -88 275 Qasmiyye Di

Divert a total of 26 Mm3/ year of water for irrigation for the Qasmiyyeh Canal

36 geometry -4 275 Aqui1 Change from the Cretaceous formation to the Eocene formation

37 geometry -10 275 Aqui2

Change from the Eocene formation to the Cenomanian formation

38 geometry -77 275 Aqui3

Change from the Cenomanian formation to the Quaternary formation

39 geometry 20 55 Aqui5 Change from the Jurassic formation to the Cretaceous formation

40 geometry 9 140 Aqui6 Change from the Eocene formation to the Cenomanian formation

41 end -99 275 End Quasmieh Outlet of the Litani River at the

sea 7 km north to Tyre

42 geometry -10 240 geom 60

43 geometry -14 340 geom 8

44 geometry 2 190 Geom dem7 45 geometry 17 140 Geome

46 geometry -24 250 Quakiyit el Jeser

47 geometry 0 300 Taibe

48 geometry -61 250 Tair falsay

49 geometry -61 250 Tair Falsay

50 geometry 2 255 Tour

Change in the direction of the River at various locations

51 start -2 425 Chaqra Subcatchment/ seasonal stream/RRM

OPTIMA, D09.2 ELARD

8


52

start 20 -30 Qelia

Start of the Litani Lower River at Qelia control point beyond the dry section after the Qaraoun lake

53 start -

27 400 Srifa Subcatchment/ seasonal stream//RRM

54 start -

39 205 Ain Yalouch Subcatchment/ spring

55 start -

50 400 Arzoun Subcatchment/ seasonal stream/RRM

56 start -

25 300 Boustane Habba Subcatchment/ seasonal stream/RRM

57 start -2 425 Chaqra Subcatchment/ seasonal stream/RRM

58 start 20 257

Disharge Deir mimes

Discharge of domestic waste water (18000m3/day) from Deir Mimess area

59 start -

79 350 Ain Bedias Subcatchment/ spring/RRM

60 start -

16 205 Ain el Basatine Subcatchment/ spring/RRM

61 start -

75 425 Ain el Kouroum Subcatchment/ spring/RRM

62 treatment 9 275 El Faqaani T Treatment station for the Deir Mimess wastewater discharge in the River

1.2. Economical analysis Conceptualization of the real model topology helps assess the economical efficiency of the baseline model scenario, such as the supply to demand ratio and the cost/benefit ratio. The calculation of the economical value of the currently existing infrastructures on the Litani River was based on local cost of water imposed by the local authority. The Litani water authority provides 26 Mm³ of water volume through the Qasmiyyeh Irrigation canal after its rehabilitation for a total area of 3220 hectares. The Litani water authority provides water from the Litani Irrigation canal through the main and secondary channels to the local farmers at a cost of 34 Euros per 1000 m² per year for surface irrigation, and at a cost of 23 Euros per 1000 m² per year for trickle irrigation. About 10% of the total irrigated area (333 hectares) are equipped with modern irrigation techniques such as trickle irrigation and consequently benefit from the reduced tariff. The cost of one-meter cube of water for irrigation is computed in Table 2.

Table 2 . Calculation of the unit cost (Euros/m³) of water for the irrigation from the Qasmiyyeh Canal

Area (m2) Fees Eu/1000m2 Total water (m3) Total fee Eu Surface 33300000 34 1132200 Trickle 2887000 23 66401 Total 32200000 26000000 1198601 Unit cost (Eu/m3) 0.046 As for domestic water consumption, the Taibe pumping station in Taibe area is providing a total of 18000m³/ day. Jabal Amel Authority that falls under the jurisdiction of the Ministry of Power and Energy provides the subscribers with 1m³ of water per day at an annual fee of 138 Euros per year. Therefore, the total cost of 1m³ of water for domestic use is 0.37 Euros.

OPTIMA, D09.2 ELARD

9

The water authorities are not charging the touristic resorts existing on the Litani River. As mentioned in section 5.1, the touristic resorts are withdrawing around 0.08 Mm³ of water from the Litani River. The Litani water authority can benefit from quantities for either domestic or irrigation purpose. An estimated rate of 0.23 euro per m³ could therefore be attributed to the water withdrawn for touristic demand. A summary of the economic factors input in the Water Resource Model for each of the infrastructure existing on the Litani River is displayed in Table 3. Table 3. The various parameters input in the water resource model for the calculation of cost/benefit ratio for the various demand nodes existing on the Litani Lower portion

Infrastructure Capital

Cost (euros)

Fixed Operation cost (Euros/ m³)

Variable Operation cost (Euros/ months)

Shortfall (Euros/m3)

Durabili-ty N (years)

Rehabilitation costs (Euro/year)

Benefit Pricing of water (Euros/ m3)

Qasmiyyeh Canal

3x106 - 2000 0.002 60+30 1 x106 0.046

Normalized 50000 0 24000 27000 - 30000 1196000 Taibe pumping station

1 x106 - 500 - 50 0.37

Normalized 20000 0 6000 - - 2430900 Touristic resorts

18400 - - 40 - 0

1.3. Objectives and constraints in the Lower Litani Basin The list of objectives and constraints was partly deduced from the lists of strengths, weaknesses, threats, and opportunities of the current Litani River Basin pointed out by the various stakeholders.

1.3.1. Strengths and weaknesses According to the stakeholders, being the longest River exclusively running in Lebanon, the Litani River presents advantageous topological features and is of significant interest for all researchers and public authorities. The volume of water that is recorded at the Qasmiyye monitoring Station ranges between 62.6 Mm3 to 400 Mm3 depending on the climatic fluctuations. Therefore, the volume of water supplied by the Litany River is relatively significant. The Litani provides work opportunities in many sectors especially the irrigation and touristic sectors. It has been also suggested that the water of the Litani River is not significantly polluted, especially in the lower portion because of the remoteness of the Litani from the major villages and cultivated lands. The weaknesses of the Basin reside in the lack of management/enforcement in the River basin, which leads to numerous violations on the River and to the imbalanced exploitation of the River water. During wintertime, the water of the Litani River is lost to the sea because of the decrease of water consumption especially for irrigation purposes in the period from December to March. The disposal of solid waste and wastewater in the River resulting from the absence of treatment plants in the area contributes to pollution of the River. The use of water consuming irrigation techniques leads to an imbalanced distribution of water on the River Basin, where some villages are not being provided domestic water, whereas cultivated areas are being supplied with an excess volume of water. The Litani Lower River lacks useful infrastructures that enable efficient use of water, such as hydroelectric stations and dams. Strengths and weaknesses are summarized in Table 4.

OPTIMA, D09.2 ELARD

10

Table 4. Main elements of strengths and weaknesses of the Lower Litani Basin

according to the results of the first working session

Strengths Weaknesses Water Availability (use of water for agricultural, touristic, and domestic purposes)

Water loss to the sea (excess of water during winter time)

Socio-economic Benefits (Job opportunities) Lack of management in the exploitation of the water (water is not being used for hydroelectric power generation, or for industries) Lack of legislation enforcement/ Violations on the River (lack of control over recreational sites on the Litani)

Awareness

Lack of action plans for the River Water Quality (limited or “light” pollution) Increasing sources of pollution (waste water

disposal in the River) not being controlled Advantageous physical characteristics/ Topology of the River

Topology of the River (hard topography, remoteness, etc…)

1.3.2. Threats and opportunities The threats and opportunities pointed out by stakeholders and deduced from issues questionnaires allowed the definition of the major fields to account for during the selection of constraints and objectives for optimization scenarios of the Litani Lower Basin (Table 5).

Table 5. List of opportunities and threats for the Lower Litani Basin

Opportunities Threats

Opportunities for irrigation and development of the agricultural sector

Increase of surface water and ground water pollution

Opportunities for electricity generation

Demographic growth; Increase of water demand

Decrease of crop productivity

Lack of citizenship spirit/ Lack of coordination activity

Unbalanced exploitation of the river in Tourism/

Water Loss to the sea

Increase in irrigation demands

Lack of funding and management resources

OPTIMA, D09.2 ELARD

11

1.2.3. Objectives and Constraints The main objectives and constraints that were set were derived from the strengths, weaknesses, threats, and opportunities will be represented on the future scenario model with different types of nodes:

1. Environmental Level flow in the river in some portions The environmental flow in the river needs to be preserved. This parameter will be represented by control nodes distributed at critical sections in the River. These nodes will account for the River section, for the inflow and demand at those sections.

2. Supply meeting consumption demand The supply meeting demand will be evaluated in the WRM output: the targeted water supply/ demand ratio is higher than 1.

3. Benefit exceeding cost in infrastructures and economic instruments This ratio will also be evaluated in the WRM model; the targeted Benefit to Cost ratio should exceed 1. The objectives that were set for the future scenarios will target these issues:

1. Increase water demand efficiency This objective aims at adopting practices in the different sectors that can secure an effective use of water, such as less consuming alternative crops, and more efficient irrigation techniques.

2. Better exploitation of the River (balanced exploitation) A better exploitation of the River can be achieved by confronting the use of minimum amount of water and the Benefit to cost ratio. It consists in analyzing the relatively most beneficial sectors or practices that could benefit from the Litani water.

3. Control sources of pollution The control of sources of pollution aims decreasing point source pollution such as wastewater discharge point by the construction of treatment plants, or the implementation of a wastewater network in the villages of origin.

4. Decrease losses to the sea In wintertime, the water availability significantly exceeds the water demand, whereas during summer time, water availability cannot meet water demand. This objectives aims at a better control over the quantities of water between summer time and wintertime in such a way to minimize loss of water to the sea and store water for periods where water supply cannot meet the demand. This can be achieved by storage infrastructures such as dams or hill lakes. This factor will also be represented by a control node at the end of the Lower Litani basin, and by the monthly “Water supply/water demand ratio” output by the Water Resource Model.

OPTIMA, D09.2 ELARD

12

The instruments that will be used to meet the objectives are divided into four different sectors: infrastructure, legal, awareness, and management as follows:

1. Infrastructure • Irrigation canal that allows the distribution of irrigation water to upstream

areas; • Two Dams (Prospective Khardale Dam; 128 Mm3) and (Prospective Kfar Sir

Dam) and/or Hill lakes which allows the retention of water during wintertime for drought seasons;

• Waste water treatment plant(s) to reduce water quality degradation due to waste water discharge;

• Hydroelectrical plant(s) that allow the “non-consumptive” use of water for electricity production;

2. Legal • Update legislation/improve enforcement; • Decrease violations on River i.e. removal of the touristic resorts or illegal

irrigation water withdraw. 3. Management • Water pricing; • Improvement of the canalization (decrease of losses) at the domestic

pumping station and Qasmiyyeh irrigation canal; 4. Awareness • Irrigation technologies (surface irrigation to drip or sprinkle) in the coastal

irrigated areas; • Alternative crops (less water consuming).

The advantages of each of the economical instrument that will be used in the future scenario model are presented in Table 6. Table 6. Advantages of the economical instruments and their role in meeting the set objectives

Increase in water

availability

Increase of water supply

Decrease of water pollution

Decrease in water demand

Decrease losses to the sea during wintertime

Increase water demand efficiency

Direct Increase

of Benefit

Infrastructure Irrigation canal 2 Dams Waste water treatment plant(s) Hydroelectrical plant(s) Hill lakes Legal Update legislation/improve enforcement Decrease violations on River

OPTIMA, D09.2 ELARD

13

Management Water pricing Improvement of the canalization Awareness Alternative Irrigation technologies Alternative crops (less water consuming)

2. Optimization Scenarios and Results

2.1. Scenario 1: Infrastructure based This scenario focuses on adding new infrastructure aiming at reaching the objectives stated above. Based on series of meetings with the Litani River Authority (LRA), the main proposed infrastructure in addition to the pre-existing ones such as the Qasmiyye Canal are mainly two dams. Both dams (Prospective Khardale Dam) and (Prospective Kfar Sir Dam) will allow the retention of water during wintertime for drought seasons, decrease losses to the sea, and secure water needs during summer time “high irrigation season”. About 12 km separate both dams.

2.1.1. Additional Infrastructure

2.1.1.1. Prospective KFAR SIR DAM The Kfar Sir Dam is proposed near the Qaiqayet El Jisr bridge where the area provides a wide lake of projected storage of about 16 Mm3. The altitude of the dam is about 110m asl. The expected height of the dam is about 50m. According to LRA, the capital cost of the dam is expected to be about 15 Million Euros. Figure 2 shows the zone of the Kfar sir prospect dam. A demand node associated with the Kfar Sir dam is supposed to irrigate approximately 2100 ha. Kfar Sir Dam is to secure a total additional demand of 0.5 m³/sec. Additionally, its implementation is expected to decrease about 5% the loss to the sea.

Figure 2. Zone of the kfar Sir dam

OPTIMA, D09.2 ELARD

14

2.1.1.2. Prospective Khardale Dam The Khardale Dam is a major prospective dam of a storage capacity of approximately 128 Mm³. It is located at an elevation of 240 m asl, with a total height of 77m. The expected cost of such a dam reaches about 120 million Euros. Figure 3 shows the area of the Khardale dam. A demand node providing water for the irrigation of approximately 9000 ha was associated to the Khardale dam. The Khardale dam is expected to decrease losses to the sea, and secures an incremental water supply of approximately 10m³/sec.

Figure 3. Zone of the Khardale dam

2.1.1.3. Deir Mimess waste water treatment plant Water quality analysis did not show major contamination in the River that could be modeled using the STREAM water quality model. Fecal coliform values increase in the sampling locations that are located downstream to a touristic resort, as well as in the location of waste water discharge at Deir Mimess. Values of BOD are below detectable limits, which may be due to the dilution effect, because the sampling has not been performed during River recession period. Despite this fact, a potential waste water plant was planned after Deir Mimess Discharge Node, in order to reduce the level of contamination in the water before the Domestic Taibe Pumping station. This node is expected to redirect approximately 70 % of received waste water as treated water.

2.1.2. Maintained infrastructures

2.1.2.1. Qasmiyye Canal The Qasmiyye Canal that is located on the coastal end of the Lower Litani River was maintained in the infrastructure Scenario. According to the Litani River Authority, the Lower part of the Litani River is supplying through an irrigation canal (Qasmiyye Canal) a volume of 26 Mm3 of water for the areas located on the coast north and south to Qasmiyye (the outlet of the Litani River), e.g., Sarafand. The Qasmiyyeh canal was constructed in 1944, and then rehabilitated in 1996, after 50 years of its construction. There are currently 1281 subscribers to the Qasmiyyeh water conveyor, which is providing water for an area of 3220 hectares of citrus and banana.

OPTIMA, D09.2 ELARD

15

The canal is derived from the Lower Litani River at the Zrariye village; water is generally conveyed by gravity. After the rehabilitation (1996-1999), the irrigated surface have increased by 15%, the total water consumption has decreased by nearly 45% due to more efficient distribution decreasing leaks and addition of regulating gates. The water shortage was decreased by 64%. Water shortage occurring in the Qasmiyye Canal is compensated by an additional volume of 13.5 Mm³ of water provided from the Qaraoun lake, which is located outside the area of study to fulfill the water shortage existing in the summer. Upon implementation of two upstream dams, the summer water shortage is to be self secured exclusively by the Litani Lower Basin.

2.1.2.2. Taibe Domestic Station According to the South Lebanon Water and Wastewater Establishment, only one pumping station existing at the Litani River in the Taibe area is extracting a volume of 18000 m³ per day from the Litani River. This pumping station is conveying water to Taibe area, which in return distribute it -after chlorination- to numerous villages (estimated population is 10 000 capita; Jabal Aamel Water Authority) located south to Litani River for domestic use. If the losses through network are estimated at 50% loss, the average water consumption in this area is 900 l/capita/day, which exceeds normal rates by at least 400%. In the infrastructure scenario, rehabilitation of the canalization of the Taibe station was applied in order to decrease losses, and consequently decrease water consumption or provide with the same amount a larger population.

2.1.2.3. Touristic resorts Following the installation of the two dams along the river, at least two touristic resorts were removed from the scenario decreasing consequently violations, local water quality degradation, and illegal water consumption from the Litani Lower Basin.

2.2. Scenario 2: Demand Change Scenario The demand scenario is an infrastructure scenario based on a future (10 years time span) decrease of water consumption in irrigation following the use of advanced irrigation techniques such as drip irrigation in the Qasmiyye Canal, the Kfar Sir and Khardale Dam irrigation demand nodes. This decrease of water consumption could also be achieved following awareness campaigns. An increase of the population of 2.5 % (based on demographic annual change estimate) was accounted in the water domestic consumption. Therefore a greater amount of withdrawn water quantity from the river was attributed to the Taibe demand node in order to provide water for a greater number of inhabitants, in the ranges of daily water consumption values.

2.3. WRM Results of New Scenarios The WRM results related to the infrastructure and the demand scenarios are summarized in Table 7. A comparison with the baseline scenario results is also shown.

OPTIMA, D09.2 ELARD

16

Table 7. Summary of WRM Results of the New Scenarios

Criterion Baseline Scenario

Infrastructure scenario

Change in demand scenario

Comments

Municipal demand (Mm3) 2.52 2.52 18.92

Increase of municipal supply/demand

Irrigation demand (Mm3) 28.60 93.47 65.43

Increase of irrigation supply/demand

Touristic demand (Mm3) 0.42 0.27 0.13 Decrease of

touristic demand Total demand (Mm3) 31.55 96.26 84.47

Net supply (Mm3) 25.58 108.3 101.2

Total consumptive use (Mm3)

21.4 93.76 82.85

Total losses (Mm3) 3.31 26.6 21.61

Better exploitation of the River water

Shortfall (Mm3) 10.15 2.5 1.63 Decrease of shortfall

Supply/ demand (%) 67.84 97.74 98.22 Increase of supply

to demand ratio

Reliability (%) 81.92 95.19 82.31 Increase of the reliability

Economic Efficiency (Euro/m3)

0.01 - 0.02 Increase in demand scenario

Water Cost (Euro/m3) 0.1 0.06 0.07 Decrease of water

cost Benefit/cost ratio 1.10 0.96 1.21 Ratio wandering

around 1

2.3.1. Results of Infrastructure scenario (water ware model) The results of both new scenarios were as follows:

• Increase of the supply to demand ratio • Decrease losses to the sea by 50%. i.e., 50% of water savings for the

summer period • Benefit to cost ratio was almost equal to 1 • Decrease of the period of shortfall

The achieved results match with most of the set objectives, and respect the environmental constraints set in the model.

OPTIMA, D09.2 ELARD

17

2.4. Optimization Scenario

2.4.1. Topology and Instruments The optimization scenario is a combination of the two scenarios, the infrastructure and demand scenarios, thus including the new infrastructures and change in demand nodes. The topology of the optimization scenario is shown in Figure 4. In the instrument section, a specific infrastructure/instruments was associated to each node selected from the list of instruments lists figuring in the model as shown in Table 8.

Figure 4. Litani Lower basin Topology model used in the Optimization runs

Khardale dam

Kfar Sir dam

Waste Water treatment plant

OPTIMA, D09.2 ELARD

18

Table 8. Type of nodes and associated infrastructures/methods in the list of instruments

Instrument Sector Type

Yearly Capital Cost

(Euros)

Demand

Reduction (%)

Loss Reduction (%)

Return

Flow Reduction (%)

Consumpti

on Reduction (%)

Associated Node

IRRIGATION TECHNOLOGIE

S (DRIP) -

Irrigation (3220 ha)

Generic Demand 500000 35 0 0 20 Qasmiyye

Canal

URBAN WATER SAVING

(PLUMBING FIXTURES) -

GENERIC

Domestic Generic Demand 12000 25 0 0 0

Taibe domestic

Plant

Pipe Leakage control Lebanon Domestic

Case specific Demand

150000 5 50 25 0 Taibe

domestic Plant

IRRIGATION TECHNOLOGY (SPRINKLER) -


Generic Demand 800000 25 85 50 25 Qasmiyye

Canal

CHANNEL LINING,

CONCRETE (Roller

Compacted Concrete, RCC)

-

Irrigation Generic Demand 100000 0 70 70 0 Kfar Sir

demand

CHANNEL LINING,

CONCRETE (Roller

Compacted Concrete, RCC)

-


Generic Demand 500000 0 70 70 0 Khardale

demand

CHANNEL LINING,

COMPACTED EARTH (CLAY) -


Generic Demand 3000000 0 70 70 0 Khardale

demand

CHANNEL LINING,

COMPACTED EARTH (CLAY) -

Irrigation Generic Demand 700000 0 70 70 0 Kfar Sir

demand

Awareness irrigation

Campaigns Irrigation


20000 25 0 5 20 Kfar Sir demand


Campaigns



20000 25 0 5 20 Qasmiyye Canal


Campaigns



20000 25 0 5 20 Khardale demand

EDUCATION and TRAINING

of URBAN WATER USERS

Domestic Case

specific Demand

5000 50 0 0 20 Taibe

domestic Plant

OPTIMA, D09.2 ELARD

19

Instrument Sector Type

Yearly Capital Cost

(Euros)

Demand

Reduction (%)

Loss Reduction (%)

Return

Flow Reduction (%)

Consumpti

on Reduction (%)

Associated Node

Kfar Sir Dam Reservoir Case

specific Demand

120000 Kfar Sir Reservoir

Khardale Dam Reservoir Case

specific Demand

960000 Khardale Reservoir

Waste water treatment plant Reservoir


200000 Waste water Taibe

2.4.2. Objectives and Constraints in the Optimization Scenario The main objectives and constraints that were set were derived from the strengths, weaknesses, threats, and opportunities, were represented on the future optimization scenario model with different types of nodes and in the set of constraints portrayed in the optimization tool.

2.4.2.1. Objectives The objectives that were set for the future scenarios are as follows:

1. Increase water demand efficiency This objective aims at adopting practices in the different sectors that can secure an effective use of water, such as more efficient irrigation techniques and better exploitation of the River water.

2. Control sources of pollution The control of sources of pollution aims decreasing point source pollution such as wastewater discharge point by the construction of treatment plants.

3. Better exploitation of the River (balanced exploitation) A better exploitation of the River can be achieved by confronting the use of minimum amount of water and the Benefit to cost ratio. It consists in analyzing the relatively most beneficial sectors or practices that could benefit from the Litani water. In wintertime, the water availability significantly exceeds the water demand, whereas during summer time, water availability cannot meet water demand. This objective aims at a better control over the quantities of water between summer time and wintertime in such a way to minimize loss of water to the sea and store water for periods where water supply cannot meet the demand. This is to be achieved by the storage infrastructures such as the two additional dams. This factor can be controlled at the end-node of the Lower Litani basin, and by the monthly “Water supply/water demand ratio” output by the Water Resource Model. The decrease of water losses to the sea by 50% with respect to the baseline scenario was achieved in both scenarios as shown in the model end node. In that way a better exploitation of the river was achieved through preserving water losses for summer time, period during which water shortage is significant.

OPTIMA, D09.2 ELARD

20

2.4.2.2. Constraints

1. Environmental Level flow in the river in some portions The environmental flow in the river needs to be preserved. These nodes account for the River section, for the inflow and demand at those sections. There are four control environmental nodes that secure that the minimum flow that is to be achieved through out the year is the flow rate not exceeded during 347 days for the year 2003-2004. The four environmental control nodes are placed after the control monitoring nodes. In the case of the proposed scenarios the control environmental nodes indicate no violation for the proposed scenarios at all levels of the River.

2. Supply meeting consumption demand The supply meeting demand will be evaluated in the WRM output: the targeted water supply/ demand ratio was set at 80%. Supply reliability was set at a minimum 80 % in the set of constraints.

3. Benefit exceeding cost in infrastructures and economic instruments The benefit to cost ratio analyzed for each model exceeded 0.8, yet in the optimization scenario this ratio was set at a minimum of 0.8 in the list of constraints.

4. Water cost The water cost varies generally between 0.046 euros/m³ and 0.37 euros/m³ depending on the water use purposes. In the list of constraints, the targeted water pricing was set at a maximum 0.05 Euro/m³.

5. Water Shortfall This parameter represents periods during which needs in water within the basin cannot be secured by the Litani Lower River especially in summer time. Upon implementation of the two dams, water shortage is expected to decrease, because of a better management of water in flood and base flow periods. Water shortfall was set at a maximum of 15% in the set of constraints

2.5. Optimization Results The optimization run conducted on the Litani Lower basin future Scenario resulted in 82 alternatives (over 1000 runs) consisting of a combination of some the proposed instruments. The best alternatives that have achieved best results in the 4 constraints are mainly those including the Kfar Sir dam and the Awareness campaigns, in addition to the leakage control, and awareness campaign for the domestic water plant. The Khardale dam has not been retained as instrument in the computed alternatives. The instruments used in optimization along with their percentage of application in the 82 retained alternatives are shown in Table 9.

OPTIMA, D09.2 ELARD

21

Table 9. Percentage of application of the instruments used in optimization run

Application (%)

Instrument Name %app %min %max

Investment (Euros)

Operation cost (Eu/unit)

Node name

IRRIGATION TECHNOLOGIES (DRIP) - GENERIC 38 0 99 108054 11

Qasmiyye Canal De

Awareness irrigation Campaigns 55 0 100 10976 0

Qasmiyye Canal De

Awareness irrigation Campaigns 56 0 100 11220 0 Kfar Sir De EDUCATION and TRAINING of URBAN WATER USERS - 49 0 100 1565 0 Taibe dem Pipe Leakage control Lebanon 51 0 100 76829 26 Taibe dem

Awareness irrigation Campaigns 59 0 100 11707 0

Irrigation Khardale de

URBAN WATER SAVING (PLUMBING FIXTURES) - 50 0 100 2830 2 Taibe dem CHANNEL LINING, COMPACTED EARTH (CLAY) - 24 0 91 112422 0 Kfar Sir De CHANNEL LINING, COMPACTED EARTH (CLAY) - 0 0 0 0 0


CHANNEL LINING, CONCRETE (Roller Compacted Concrete, RCC) 13 0 83 43085 43085


CHANNEL LINING, CONCRETE (Roller Compacted Concrete, RCC) 23 0 96 16512 82562 Kfar Sir De IRRIGATION TECHNOLOGY (SPRINKLER) - 27 0 92 121447 0

Qasmiyye Canal De

Table 10 shows that benefit/cost ratios were in all the selected alternatives greater than 1 ranging between 1.13 and 2.2. The total shortfall ranges in all the alternatives between 3.8 and 9.5%. Water pricing ranges between 0.04 and 0.05 Euro/m³.

Table 10. List of constraints applied in the optimization model

Type MAX/MIN Results achieved in Optimization

Selected set of constraints Benefit/Cost 0.8 (Max) 2.22 (Max) Supply/demand 0.8 (Max) 1 (Max) Shortfall 15% (Max) 3.8 (Min)-9.5 (Max) % Water pricing 0.05 Euro/m3 (Min) 0.04-0.05 Euro/m3 Other constraints Total Unallocated - 19.6-50 Mm3 Reliability of Supply - 84-100%

OPTIMA, D09.2 ELARD

22

Figure 5, 6, 7, and 8 show the frequency distribution of the results for each of the constraints in the set of alternatives computed upon the running of the optimization model. According to generated statistics, there is a linear inverse correlation in plots of the water cost versus cost-benefit ratio, and supply/demand ratio and water shortfall. A linear correlation exists between supply to demand ratio and Benefit /cost ratio in most of the analyzed alternatives. A first screening of the 82 solutions consisted in selecting the alternatives having the supply/demand ratio equals to 1. A second screening consisted in the selection of alternatives combining low shortfall and high benefit cost ratio exceeding 1.5. Nevertheless all alternatives including instruments related to the Khardale dam were discarded, since Khardale dam was not selected in the set of feasible alternatives.

Figure 5. Frequency distribution for water cost criteria of the 82 retained alternatives

computed in the optimization

Figure 6. Frequency Distribution for the Benefit/Cost criteria for the retained 82 alternatives

OPTIMA, D09.2 ELARD

23

Figure 7. Frequency Distribution for the Supply/demand criteria for the retained 82 alternatives

Figure 8. Frequency Distribution for the Total shortfall criteria for the retained 82 alternatives

Figure 9. Frequency Distribution for the Total unallocated criteria for the retained 82 alternatives

OPTIMA, D09.2 ELARD

24

The potential 13 retained scenarios fulfilling all the set constraints aim at decreasing water consumption and demand, losses, and return flow. The scenarios 45, 23, 39, and 49 presented in Table 11 are characterized by a relatively low shortfall not exceeding 4%. These scenarios mainly include the shift to drip Irrigation, awareness campaigns, and losses control in domestic supply pipes. Other retained scenarios having a higher shortfall, rely on the use of the Channel concrete lining, to decrease losses and return flow, in addition to the awareness campaigns in both domestic and irrigation sectors, and less consumptive/more efficient irrigation methods such as sprinkle and drip irrigation at variable application percentages (Table 11).

Table 11. Retained potential scenarios based on the set of constraints, economical analysis, and potential combination of instruments

Supply/demand

Shortfall (%)

Water Cost (Euros/m3)

Benefit/Cost

IRRIGATION TECHNOLOGI

ES (DRIP) -Qasmiyye


Campaigns-Qasmiyye


Campaigns-Kfar Sir

EDUCATION and TRAINING of URBAN WATER USERS -

Pipe Leakage control

Lebanon

URBAN WATER SAVING

(PLUMBING FIXTURES) -

GENERIC

CHANNEL LINING,

COMPACTED EARTH (CLAY) -Kfar Sir

CHANNEL LINING,

CONCRETE (Roller

Compacted Concrete,

RCC) -Kar Sir

IRRIGATION TECHNOLOG

Y (SPRINKLER)

-Qasmiyye35 25 25 50 5 25 0 0 250 0 0 0 50 0 70 70 850 5 5 0 25 0 70 70 50

20 20 20 20 0 0 0 0 25Alternative82 0.997 3.976 0.064 1.13Low Shortfall ranges between 3 and 4 %Alternative49 1 3.915 0.044 1.988 0 0 100 0 100 0 0 0 0Alternative39 1 4 0.043 1.886 0 100 100 48 100 0 0 0 0Alternative23 1 4.027 0.046 1.82 48 0 0 52 100 35 0 0 0Alternative45 1 3.941 0.049 1.716 0 100 100 79 0 0 0 58 0Higher Shortfall 0 0 0 0 0 0 0 0 0Alternative57 1 9.186 0.045 2.133 0 100 100 84 100 20 0 0 0Alternative58 1 9.174 0.043 2.053 32 0 100 56 100 91 0 0 0Alternative63 1 9.244 0.047 1.871 0 0 0 0 0 30 0 83 25Alternative47 1 9.313 0.047 1.843 26 0 100 78 0 0 62 0 0Alternative15 1 9.343 0.05 1.809 0 0 0 0 100 66 57 0 0Alternative34 1 9.346 0.048 1.805 0 100 0 0 0 0 0 57 81Alternative32 1 9.364 0.047 1.747 31 100 0 30 0 0 0 57 0Alternative44 1 9.304 0.047 1.717 46 100 0 79 0 17 0 51 46Alternative26 1 9.385 0.048 1.452 92 0 100 0 0 0 56 0 0

Baseline

Demand Reduction (%)Loss Reduction (%)Return Flow Reduction (%)Consumption Reduction (%)

OPTIMA, D09.2 ELARD

25

3. Further Steps A participatory stakeholder meeting will be held in May to discuss the optimization results, discuss stakeholders preferences and reactions. The results of the workshop will be used to finalize the optimization process. One of the interesting results in this study is the fact that the Khardale dam, which has already been approved for implementation by LRA, was not retained. This issue shall be discussed during the workshop and could lead to changes in decisions taken in the future. Most of the implementation measures proposed are not costly and can be implemented. Given the involvement of LRA and other stakeholders in the project, ownership of results is high, which could lead to higher probability of implementation of the selected alternatives.

optimisation for sustainable water resources management · optima, d09.2 elard 1...

Documents