The project, DW050 Muaither Area Sewage CP773!1 Package 1 is situated in Zone 55 in west of the Muaither Precinct, in the municipality of AI Rayyan, north of AI Sailiya Road. The main aim of this project is to provide a positive sewerage outfall to project DW015 - Rawdat Abal Heeran by constructing a deep trunk sewer which will collect and discharge the flows to the existing PS 32A, which pumps the sewage to the Doha West STW. This project also provides positive outfalls to other projects in the West Muaither area, namely the QAF development, DW044 and part of DW002 where no sewerage infrastructure is currently available. Figure 1-1 shows the project catchment boundary.
The project comprises approximate 6.6km long deep gravity trunk sewer (excluding provisional section of sewer) through DW044 and DW017 project area with internal diameter ranging from 800mm to 1000mm. It also consists of 1.3km length of stubs (excluding provisional section of sewer) within DW044 area to allow surrounding sub-catchments to discharge into the proposed trunk sewer in the future. Future connections to the stubs are not in the scope of this project. Due to the trunk sewer being at depths greater than 6m, pipes will be built using trench less construction techniques.
It should be noted that although the OAF development is included as a provisional sum in the contract documents which may be instructed by the Engineer.
The Contractor is responsible for constructing the trunk sewer according to OCS 2010 specification and complete in all respect as per Technical Specifications and drawings enclosed in the tender documents.