Abu Dhabi celebrates tunnel breakthrough

UAE-based Abu Dhabi Sewerage Services Company (ADSSC) and its programme manager CH2M HILL have completed construction of the city’s new main sewer tunnel.

The tunnel marks a milestone achievement in Abu Dhabi’s billion-dollar Strategic Tunnel Enhancement Programme (STEP). The 41 km long tunnel is the major component of one of the largest and longest gravity-driven sewerage networks in the world.

“We used a total of eight huge tunnel boring machines (TBMs) to excavate the 41 km of deep tunnel so the recent breakthrough of the last TBM was celebrated as a significant programme milestone and one we have been working towards since 2008,” said Bob Marshall, CH2M HILL STEP programme manager.

“With the deep tunnel complete, we can shift our attention to the network of link sewers that connect into the tunnel on both Abu Dhabi Island and the Mainland.”

Alongside the 41 km main sewer tunnel, the project also includes 43 km of smaller diameter new link sewers up to 3 m in diameter, and a large pumping station at Al Wathba Independent Sewerage Treatment Plants.

Once completed in 2015, the infrastructure will triple the capacity of Abu Dhabi’s sewerage network. The system will provide for an average wastewater flow of 800,000 m³/day, with an ultimate capacity of 1.7 million m³ per day by 2030.