Widening 4.7km of the existing SH20 motorway between Walmsley Road, Manukau Road and Queenstown Road
Construction included a 544m x 22.1m duplication of the existing Mangere Bridge; modification or replacement of four existing bridges, a median-divided carriageway with four lanes in each direction between Rimu Road and the Gloucester Park interchange, and a minimum of three lanes elsewhere and a bus shoulder lane in both directions
