Without a "fixed link" to the BC mainland, there is little probability of substantial improvements in the mobility characteristics of some of the more congested or heavily signalized sections of the Island Trans-Canada Highway or the Nanaimo Parkway. Proposals have been made for this kind of link for over a century. Because of the extreme depth and soft seabed of the Georgia Strait, and the potential for seismic activity, a bridge or tunnel would face monumental engineering, safety, and environmental challenges at a prohibitive cost.