The project, which is valued at BD 25 million ($65 million), will entail replacing the two existing causeway bridges and widening the Sitra highway crossing. In addition, the selected contractor will expand both interchanges at either end of the causeway. Pilings underpinning the existing bridges are considered inadequate to support 40-tonne trucks which have to be diverted creating a major bottleneck (Bahrain, MEED Special Report, 30:5:03, page 26).