President of the Public Works Authority (Ashghal) Eng. Nasser bin Ali Al Mawlawi inaugurated the commencement of excavation works for Mesaimeer Surface and Ground Water Tunnelling, a significant project being undertaken by Ashghal to enhance Qatar’s drainage network.
This inauguration was conducted during a site visit by Ashghal’s President to the work launch site at Al Thummama area. He was accompanied by HE Italian Ambassador to Qatar Guido De Sanctis and senior officials from Ashghal including Director of Infrastructure Affairs Jalal Yousef Salhi and Director of Asset Affairs Hamad Mohamed Al Tamimi. Also present at the inauguration were representatives from Ashghal’s roads and drainage Operations and Maintenance department, CDM Smith the project consultant, Salini Impregilo Construction Company the project contractors, and Herrenkenecht, German manufacturing company for the Tunnel Boring Machines (TBM) being used to excavate the tunnels.
The Mesaimeer tunnel for surface and ground water is one of the key drainage projects within Ashghal’s plans for upgrading Qatar’s drainage network. The tunnel will run under the F-Ring Road and extends 9.7 km. It will stretch 5.4 km from Al Thumama to the west and 4.3 km to the east to the planned pumping station near the new Hamad International Airport.
Being undertaken by Ashghal to enhance Qatar’s drainage network, the Mesaimeer surface and ground water tunnel will alleviate Doha’s storm water by transporting it from a 170 km? of catchment area, covering southern and western parts of greater Doha. The tunnel will be linked to the existing and planned drainage network in the areas that it will traverse.
To allow access for inspections and regular maintenance of the tunnel, an operations and maintenance plan has been developed to ensure satisfactory operation of all elements. This will be facilitated through 21 access shafts linking ground level to the 20 – 30m depth of the tunnel.
The specially manufactured TBMs operating through pressure balanced excavation technology are ideal for Doha ground conditions at a depth of 30 metres. This technology will facilitate the construction of essential infrastructure tunnelling which is paramount to accomplish a sophisticated tunnel network.
Over the past 16 months, Ashghal has been involved in rigorous planning and preparation process for the tunnelling project. The works included design, fabrication and installation of TBMs, geotechnical investigations and site mobilisation. Excavation works were conducted to prepare the launching tunnel and additional elements to support the TBMs such as portal cranes and other enabling requirements were installed.
The Mesaimeer tunnel project is scheduled to be completed by early 2017. Ashghal also reported that design and tender documents preparation for phase 2 of the project are being finalised. This second phase includes a pumping station with a capacity of 19 cubic metres per second, which will ultimately discharge the collected storm water from the Mesaimeer tunnel through an offshore outfall several kilometres away from the shoreline, thus ensuring protection of the shoreline and surrounding environment.
Source : Qatar News Agency