TENDER NO. 181/2008

MUSCAT WASTEWATER SCHEME PROJECT

CONTRACT NO. 3

BAUSHER NETWORK – AL KHUWAIR NETWORK

Scope of Works

The Tenderer is advised that the proposed Bausher Network system in its entirety has been divided into four separate Contract areas, as further described in the Particular Specification.

Works Carried Out by Previous Contractor

The Tenderer is advised that a part of the works contained within this Contract site area have already been carried out by another Contractor under a previous contract.

The works required under this Contract will require the incorporation of all suitable construction carried out under the previous contract.  This will involve inputs in terms of survey & site investigation, cleaning, verification, repair and preparation to ensure that the works are complete to the standard that was originally intended.

The Tender Drawings shall show the approximate extent of the works carried out by the previous Contractor.

Al Khuwair Network System – New Network Construction

The construction of the Al Khuwair network system shall be completed under this Contract.  This will include all property connection construction as defined in the Specification.  The approximate situation in terms of work completed/remaining is as follows:

These new network sections will include the installation of a Fibre Optic Duct system.  The extent of fibre optic cable installations to be confirmed by the Engineer.

Al Khuwair Network System – Existing Network Rehabilitation

In sections of the Al Khuwair area there is an existing network of sewer pipes.  This network has never been operational.  This existing infrastructure shall be incorporated into the overall Al Khuwair Network to be delivered under this Contract.  To facilitate this incorporation the existing system shall undergo a programme of rehabilitation works as detailed in the Tender Drawings.  At present there is no provision of property connection infrastructure to these areas.  The works will therefore include all property connection construction as defined in the Specification.  The approximate property connection quantities for this area are included in the property connection information given in the above table for ‘New Network Construction’.  The approximate situation in terms of rehabilitation work to be carried out is as follows:

Treated Effluent (TE) System:

The TE irrigation system will operate from the Al Ansab Sewage Treatment Plant.  A 1000mm dia. main will run parallel to the twin rising main from the Central Pumping Station.  The system will be extended in several directions to provide irrigation supply throughout the Bausher Network area.

This irrigation supply system extends into the Al Khuwair contract area at the locations indicated on the Tender Drawings.

A Fibre Optic Duct system will be constructed along the route of the TE irrigation main for system control and monitoring purposes.  The extent of Fibre Optic cable installations to be confirmed by the Engineer.  This duct system will be required to interface with a similar Fibre Optic Duct system to be constructed under Contract No 2.

The approximate situation in terms of work completed/remaining is:

TE Main Completed    -        0 km

TE Main Remaining    -        8.25 km

In further detail, Contract No 3 consists of the following:

·         Sewer network construction, as detailed in the Tender Drawings.  This network construction will interface with the sewer network construction to be carried out under Contract 2, at the locations indicated on the Tender Drawings.  This interface will generally be located to the south of the major road artery the Sultan Qaboos Highway, at locations where the overall network crosses the Highway.

·         Some network sections shall be constructed by microtunneling construction.  Such sections are indicated on the Sewer Layout drawing as “NDRC” and additional sections may be instructed during the operation of the Contract.

·         The above sections of microtunneling construction may be omitted from the Contract and constructed by another Contractor.  In such circumstances there will be a requirement for close cooperation and coordination between the two Contractors, primarily via the regular coordination meetings detailed below.  Where the microtunneling works are omitted, the value of such works shall not be considered for the purposes of any assessment under Conditions of Contract Clause 52(3).  The successful Tenderer will be advised during the mobilisation period, or earlier, of his obligations in respect of the microtunneling work.

·         Incorporation of works carried out by previous Contractor.  This will require such works to be cleaned, appraised and approved for use, where necessary.

·         Sewer network rehabilitation works as indicated in the Tender Drawings.

·         Property survey and indicative Property Connection (House Connection) design, where this information has not been supplied in the tender documents.  In all instances it is the responsibility of the Contractor to finalise the Property Connection design; any indicative details that are shown in the tender documents are intended as a suggested layout and the Contractor is responsible for all necessary revisions to optimize the property connection and to mitigate for any onsite conditions encountered.

·         Construction of individual Property Connections, by a two stage dry & wet procedure.

·         Construction of Treated Effluent irrigation main as indicated in the Tender Drawings.

·         Installation of fibre optic duct system in same trench as Treated Effluent irrigation main; fibre optic cables to be installed by others.

·         Construction of Fibre Optic Duct network in same trench as the sewer network construction; the extent of Fibre Optic cable installations to be confirmed by the Engineer.

·         Design and construction of minor network pumping stations and rising mains to gravity sewer network.  The Tenderer shall note the possibility that a requirement for additional minor pumping stations may be identified during the operation of the Contract.

·         Procurement of all necessary No Objection Certificates wherever a valid No Objection Certificate has not previously been obtained.  Maintain validity of all No Objection Certificates until completion of relevant section of the works.

·         Procure and maintain validity of Excavation Permits for all installations.

·         Participation in interface coordination with all other relevant contracts involved in the Muscat Wastewater Scheme, including but not limited to attendance at regular coordination meetings.

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