The design contract will cover two light rail lines running north-south and east-west over a total distance of about 38 kilometres. The project will cost an estimated SR 1,500 million ($400 million).

'The project will take 10 years until realisation,' Jalal Nafakh, director of ADA's transportation unit, told the Institute for International Research (IIR) Gulf Traffic/MENA Rail Congress in Dubai on 10 December. 'We are still not sure whether the project will be implemented as a DB [design-build], a DBO [design-build-operate] or a DBOF [design-build-operate-finance] project. We are working on this but we need to find out more details first.'

ADA also expects to choose a consultant for the project to carry out a study determining the final scope of the LR network in January. Seven companies, including Dornier, the US' Parsons Brinckerhoff Internationaland France's Systra, submitted proposals for the contract earlier this year. The study is expected to take 15-18 months.

While the 30 per cent design will be based on overground options only, the comprehensive study might reintroduce an underground element .