During the early 1980s, it was anticipated that traffic through the tunnel would rise on the completion of the M25 in 1986. At the time, the expectation was that other routes in London would be improved instead, diverting 15% of traffic away from the tunnel. In 1985, the Transport Minister, Lynda Chalker, announced that the number of toll booths would be increased to 12 each way, but concern grew that two tunnels would not be able to cope with the full demands of a completed M25.