The pipeline project will convey water from the planned Ras al-Zour independent water and power project (IWPP) at Dammam to the capital, Riyadh. Three engineering, procurement and construction contracts have been tendered by the client, the Saline Water Conversion Corporation.

Al-Rashid is the low bidder for one package covering three pumping stations along the route of the pipeline, with a bid of $1bn.

Two further packages cover the construction of the pipeline itself. Mapa is understood to be the low bidder for the first segment, from Dammam to a pumping station at Al-Jandalia. The value of its offer is not known.

Al-Rashid is the front runner for the second section, from Al-Jandalia to Riyadh, after submitting the lowest offer of $400m.

The pipeline will stretch for 268 kilometres between Ras al-Zour and Al-Jandalia, and a further 213km from there to Riyadh. In total, the project requires the laying of 943km of pipes.

Bids for the project were submitted in mid-June, following a delay from April as the consultant, Germany's ILF Consulting Engineers, made changes to the proposed pipeline route.

The Ras al-Zour complex will have a capacity of 850-1,100MW of power and 220 million gallons a day of desalinated water.