The justification for the additional expenditure and complexity related to digging a tunnel for part of the way, rather than raising that section of the bridge, was to avoid interfering with air traffic from the nearby Copenhagen Airport, to provide a clear channel for ships in good weather or bad, and to prevent ice floes from blocking the strait. Construction began in 1995, with the bridge opening to traffic on 1 July 2000. The bridge received the 2002 IABSE Outstanding Structure Award. See Jorgen Nissen, and others from Arup's, receiving this award for the bridge in the video put together by Arup's: https://www.arup.com/perspectives/jorgen-nissen