The Ministry of Works & Housing has invited companies to prequalify by 7 September for the contract to expand the Sitra causeway. The BD 25 million ($65 million) project aims to ease congestion by allowing the crossing to support heavier vehicles (MEED 2:4:04).The project calls for the replacement of the existing bridges with two new concrete bridges with lengths of 200 metres and 400 metres, and embankments with a total length of 2.4 kilometres, adjacent to the existing causeway. The new structure will support a four-lane carriageway, and three grade-separated interchanges are to be constructed at either end and in the middle of the crossing. Dredging of about 1 million cubic metres of material will be required to improve tidal flow in Tubli Bay. The existing Sitra bridges will be demolished. The Danish/local COWI Almoayeddrew up designs for the expansion.