Kesrouane Coastal Area Water Supply Project
One of Japanese Projects in Lebanon
The Government of Lebanon has received a loan from Japan Bank for International Cooperation (JBIC), (currently Japan International Corporation Agency - JICA) towards the cost of implementation of Kesrouane Coastal Area Water Supply Project.
A contract was concluded between CDR and the Joint-Venture BARESEL AG / AL TAJJ Est. for the construction of this project, and between CDR and the Joint-Venture Dar AI Handasah Nazih Taleb & Partners and Montgomery Watson for the supervision services.
Description of the Proposed Works
The project aims to supply the coastal and surrounding areas of Kesrouan Caza by potable water from EI Madiq spring and boreholes emerging in Nahr Ibrahim River. The water is conveyed thru a 4 km Tunnel into the main transmission lines to the reservoirs and distribution networks of the Coastal and most populated villages of Kesrouane starting from Aaqaibe to Nahr EI Kalb (including Aaqaibe, Kfar Chiham, Bouar, Safra, Adma, Tabarja, Kfarhbab, Sahel Aalma, Ghazir, Jounieh, Batha, Daraoun, Ghosta, Sarba, Hantouch, Zouk Mikael, and Zouk Mosbeh).
The main project executed components are:
• 15 Km GRP Transmission pipes, diameter up to 1,000mm
• 57 Km DI Water supply branches, diameter up to 600mm
• 45 Km Polyethylene Distribution networks, diameter up to 22smm
• 11 Water reservoirs, capacities ranging between 500, 1,000 and 3,000m3 (Civil & MEP)
• Including Pumping Stations with power up to 250KW (Civil works)
• Sand removal Basin, Control and Chlorination systems (Civil & MEP)
• Hydraulic tunnel: 4.03 km long and 3.0 m minimum final lined diameter. A 1,000mm
• potable water pipe is laid inside this tunnel, conveying a flow of about Im3/s along
• with an open channel for irrigation water conveying a flow up to 2m3/s
• Catchment works for Madiq spring
• 5 Boreholes with flow up to 150 L/s each in Nahr Ibrahim River bed
In addition, and in order to reduce pollution at Jounieh Bay Coastal Road (modified Routing of the transmission line), additional sewage works were conducted including: 4.5 Km pumping sewer line from SPS to sea outfall, ND 700mm and 2.5 Km Gravity sewer line along a section of the coastal road, diameter up to 700mm.
Reservoirs and Madiq Works
Decree No. 5348 dated 21/04/2001 and decree No. 7846 dated 30/04/2002 were released for
the land accusations for the reservoirs and pumping constructions.
The main construction works of the available pumping stations and reservoirs have been executed, namely Upper Sahel Aalma/Jounieh reservoir (1000m3), Upper Sahel Aalma reservoir (1000m3), Upper Bouar reservoir (500m3), Lower Bouar pumping station and reservoir (500m3), Lower Kfarchihham pumping station and reservoir (1000m3), Upper Aaqaibe reservoir (500m3), Lower Aaqaibe pumping station and reservoir (1000m3), Daraoun pumping station and reservoir (1000m3), Batha pumping station and reservoirs (2x500m3), Ghousta reservoir (1000m3), Sarba reservoirs (2x3000m3), Bkirki pumping station and reservoir (500m3).
Remaining reservoirs were excluded from the project scope, however the remaining finishing
and MEP (pipes and fittings) works, for the executed lower level reservoirs (fed by gravity) are
completed. The upper level executed reservoirs are partially taken over by Water Authorities
and set in service by conveying water from higher levels with no pumping.
the raw water, collected from the mentioned boreholes (no. 5) with a total flow up to 650 L/s and from the spring, will be treated through removing the suspend sand within the sand removal basin and disinfection (Chlorination).
It shall be noted that the spring catchment works were also executed and proved to be of high efficiency by increasing the amount of the gravity collected water either from the spring in dry season or from the boreholes with maximum levels of underground waters in wet seasons.
The main transmission line section from (between Nahr Ibrahim and Tabarja) was completed by 2005. On the other hand, the remaining transmission pipeline routing, extending from Adma branch to Zouk, has been relocated to the Coastal Road of Maameltein and has been lately completed. Along with this section, sewage works were also conducted in order to replace the existing pumping and gravity sewage leaking lines causing pollution to the surroundings.
Transmission branch lines to all project reservoir locations were completed along with the all project villages' distribution networks (Aaqaibe, Kfar Chiham, Bouar, Safra, Adma, Tabarja, Kfarhbab, Sahel Aalma, Ghazir, Jounieh, Batha, Daraoun, Ghosta, Sarba, Hantouch, Zouk Mikael, and Zouk Mosbeh). Additional distribution lines on the Costal road were completed too, and temporary /permanent connections to existing pumping stations and networks were completed to ensure permanent serviceability of water supply.
In total, the executed transmission and distribution network is of 120 Km covering the whole area of Kesrouane Caza abovementioned coastal villages.
TBM related works in terms of starting chamber (blasting), platforms, site arrangements, installation of generators / air compressors, workshop, tipping area and site batching plant, were completed by setting out and initial operation of the TBM in year 2005.
Survey works have been performed for the accurate setting out of the alignment, entry and exit, it has been sustained systematically during excavation progress to ensure application of deviation correction measures where needed.
Executed Tunnel entry access road: it consisted of the construction of retaining walls assuring the separation between the road that enclose the pipelines and the river. Additional works for the stabilization and the protection of the walls footings have been executed. Pipes have been laid and backfilled along the executed part of the walls.
Executed Tunnel exit access road: to achieve the construction of retaining structure between the existing road of Ma'aisra and the tunnel exit access road and platform. The works consist of excavation, projection of shotcrete over steel reinforcement, then boring of nails that are reinforced and filled with cement rout to ensure retaining of the platform surrounding.
Initial start up of the TBM machine took place by July 2006 were the first 100 m were executed to connect the machine back up system (conveying belt...). During excavation, immediate rock-bolting using expandable materials were executed where necessary. Back up equipments (rails, locomotives, hauling bins to the tipping area) and materials testing (shotcrete, dowels ... ) were performed systematically. Due to the encountered geological conditions, the rate of excavation progress was sometimes low.
The mentioned works were being conducted continuously on a NON-stop basis, the level of progress was noticeable despite the faults and water inflow existence, by September 2008 the breaking through took place. Shotcrete (wire mesh and dowels) final lining works were conducted after that based on the excavated geology assessment.
In order to take benefit from the inflowing water for future use in the irrigation channel as an additional quantity, and in order to protect the pipe with reinforced concrete casing, the Tunnel inside section was modified.