The expressway was considered critical for the development of the planned $42million Yorkdale Shopping Centre, southwest of the Spadina-401 interchange. At one point, the Yorkdale development was under the threat of cancellation without the approval to proceed with the Spadina. Only after Metro Council formally approved the whole Spadina project in 1962, did the land owners T. Eaton Co. Limited and developers Webb and Knapp (Canada) Limited announce construction. The interchange of the 401 with today's William R. Allen Road has connections with the private roadways of Yorkdale.