Excavation work for one of the country’s biggest drainage tunnels begins

The Public Works Authority (Ashghal) has started the excavations of the main drainage tunnel within the Drainage Tunnel Project in Al Wakra and Al Wukair, which will extend for over 13 km, in a new step towards implementing its plan to develop the drainage network infrastructure in Al Wakra and Al Wukair.
Eng. Khalid Saif Al Khayareen, Drainage Networks Projects Department Manager in Ashghal, said the main tunnel will accommodate the drainage flows from the current and future drainage network in different areas in Al Wakra and Al Wukair, and transfer these flows to Al Wakra and Al Wukair Sewage Treatment Works, which will have an initial capacity of 150 million litres per day and is set to be the first project in the country to be implemented through Public-Private Partnership (PPP) in the field of drainage projects.
Al Khayareen pointed out that the drainage tunnel in Al Wakra and Al Wukair is one of the largest drainage tunnels in Qatar so far, with a total length of about 13.3 km and a diametre of 4.5 metres. The cost of the project amounts to QR859,100,000.
The main drainage tunnel, which will operate by gravity, will extend from Al Khuwaytim to the Birkat Al Awamer areas. The excavation works will be carried out by two deep Tunnel Boring Machines (TBM), at a depth of about 60 metres underground.
The TBMs incorporate advanced technologies since they were specifically designed to suit the geological characteristics of Qatar, to ensure the efficiency of the excavation process and provide the maximum safety standards for workers. This is in addition to guaranteeing that no damage will be caused to the services or facilities surrounding the tunnel.
The project includes the construction of eight shafts from land to the bottom of the tunnel, with depths ranging from 50 to 63 metres underground. These shafts are made to execute the deep excavation works, and carry out inspections and periodic maintenance of the tunnel. The shafts will also help in connecting the tunnel with the drainage network in nearby areas in the future.
The design life of the main drainage tunnel is about 100 years. The tunnels innovative design adopts the best construction practices and will be implemented in accordance with international standards of health, safety, environment and sustainability management. That is in line with the countrys vision in the sustainable infrastructure field.
In addition, the project consists of two additional packages which are the Drainage Networks Branches in Al Wakra and Al Wukair, and the Treated Sewage Effluent Lines in Al Wakra and Al Wukair.
This integrated network provides an advanced and comprehensive wastewater management solution at low cost of operation and maintenance. The total cost of the project with its three packages amounts to more than QR1.5 billion.
Ashghal started the project implementation works in November 2020, and it is expected that works will be completed in the Q2 of 2024.