A tunnel boring machine (TBM) working on the Red Line North of the Doha Metro project has stopped working after hitting a pocket of underground water.

According to sources working on the project, the earth pressure balance (EPB) TBM was dipping below another metro line when it hit a pocket of water, flooded both tunnel and machine. It is understood the machine was running in open mode when it encountered the water and the gate to close off the ingress of water and material could not be moved into place quickly enough.

The project client, Qatar Railways Company (Qatar Rail), has confirmed the TBM and tunnel has hit a pocket of water and flooded. It adds that it is a small issue requiring minor mechanical repairs and no impact on the overall programme of the contract is expected.

Other sources working on the project say that the flooding could cause significant delays if the machine needs to be excavated out of the ground for repairs. They say if that is the case, there may be a delay of four to six months.

A consortium of Italy’s Salini, South Korea’s SK Engineering & Construction and local Al-Misnad Galfar Engineering & Contracting won the contract to complete the underground sections of Red Line North in April 2013. 

Contractors working on other underground sections of line for the Doha metro are watching developments closely. Sources in Doha say that underground cavities are hindering the progress of the tunnelling work, and contractors are now worried that what happened on Red Line North may also happen to them.

Many of the world’s leading construction companies are working on the underground sections of Doha Metro. A consortium of Greece’s Aktor, Turkey’s Yapi Merkezi, STFA also of Turkey, India’s Larsen & Toubro and the local AlJaber Engineering is working on the Gold Line;

A team of the local/French QDVC, South Korea’s GS Engineering & Construction and the local Darwish Engineering is working on Red Line South; and a consortium of Austria’s Porr, Saudi Binladin Group and the local HBK Contracting Company is working on the Green Line.