CARS would offer a cash-rate return for 3 to four years over the construction stage of the project, Mr Cox said. The Orbital, at 39 kilometres, will be Australia's longest tollway and will run through the fastest-growing area in Australia, joining underdeveloped industrial land with ports, roads and rail links. With no bridges or tunnels, construction risks were minimal, Mr Cox said. Transurban has also lodged a bid for construction of Sydney's Lane Cove Tunnel and is examining ventures overseas. "We are currently looking at a couple of alliance opportunities which may require some modest seed capital," Mr Cox said. "However, no major direct equity commitments are under consideration."