The project's scope of work involves the design and construction of 73 kilometers of 400mm to 2400mm in diameter lateral interceptor sewers with installation at depths of between 4 meters and 40 meters using microtunnelling and pipe jacking techniques located at Al Muntaza, Doha, Qatar. The ground conditions across the area are expected to comprise weak rock with a maximum strength of 45 MPa, with a high groundwater table.Bids have been submitted for the main contract and are currently under evaluation. TunnelTalk understands that a total of six slurry/EPB machines, ranging in diameter between 3m and 4.5m, will be procured for excavation of the central spine of the Qatari capital’s largest ever sewerage mega-project. Construction of the main interceptor – which is similar to neighbouring Abu Dhabi’s STEP project – is divided into three design-build lots: north, south and central. The north and south lots, which together total 30km in length, to i.d.s of 3m and 4.5m, are awarded by the Qatar Public Works Authority, Ashghal, to a joint venture headed by French construction giant Buoygues, for a combined contract sum of €550 million.