Abu Dhabi’s green tunnel construction on schedule

Considered one of the largest and longest gravity-driven sewerage networks in the world, a 41-kilometre-long ‘green' tunnel in Abu Dhabi is on schedule, a senior official has said.
The 41-kilometre-long main tunnel and 42-kilometre-long link service tunnels will be completed by the first quarter of 2015, Alan Thomson, Managing Director of Abu Dhabi Sewerage Services Company (ADSSC), an Abu Dhabi Government entity responsible for waste water management in the emirate, told Gulf News.
The pumping stations as part of the project will be completed by the end of 2015, and after completion, the project will be commissioned in phases, Thomson said.
The entire project, which began in 2009, is expected to be operational by 2016, he added.
The eco-friendly tunnel will drastically reduce the carbon footprint of Abu Dhabi's sewerage system and save Dh4.2 billion which can be spent on energy and maintenance costs in the next 25 years.
The project, named Strategic Tunnel Enhancement Programme (STEP), will cost Dh5.7 billion. The deep tunnel, starting at 27 metres underground and reaching a depth of 100 metres, should not require regular maintenance for the next 80 years.
The tunnel, starting from Karama area in Abu Dhabi city to Al Wathba treatment plant, will triple the capacity of Abu Dhabi's sewerage network.
The existing system deals with 400,000 cubic metres of sewage a day, but the new tunnel can carry 1.7 million cubic metres of sewage, which is the expected demand by 2030.
The new tunnel will do away with 34 pumping stations in the existing system that consume huge amounts of energy. They will be replaced by one pumping station at Al Wathba treatment plant, Thomson said.