The major new line is one of four being developed by Qatar Railways Company for the Doha Metro transit system.
The contract extension has an estimated value to the joint venture of approximately QAR157m (US$43.1 million). Hill is an 80% partner in the joint venture, which is with Astad Engineering Consultancy & Project Management Company.
The Green Line runs from Al Mansoura to Al Riffa, passing through Education City and also serving Hamad Hospital, Al Shaqab and the upcoming Qatar National Library. The Green Line will include 11 stations over approximately 22km and is expected to accommodate 140,000 passenger trips per day by 2021.