Doha Bank is backing a project financing to be used to construct the 2.2 billion riyal ($604.3 million) Water Security Mega Reservoirs Project for Qatar General Electricity & Water Corporation (KAHRAMAA), the bank has said. The deal has been signed with Leighton Contracting Qatar, a unit of United Arab Emirates-based Habtoor Leighton Group, with Doha Bank adding in the bourse filing it had already issued project-related guarantees to the company. The reservoirs in the project, named Rawdat Rashed, have a capacity of 100 million gallons each and will be the largest reinforced concrete reservoirs in the world, the statement said, without mentioning the total capacity of the project.