The CTA is considering several plans to modernize the Purple Line and Red Line north of Belmont. One of the alternatives calls for building a subway from just north of Belmont to Loyola which would replace the existing elevated structure.

Under this alternative, the Wrigley Field station would be under Sheffield between Addison and Waveland, with the main entrance at Addison and Sheffield and a secondary entrance at Waveland and Sheffield. In addition, the new Irving Park station would have a secondary entrance just two blocks north of the bleacher entrance (at the corner where Sheffield, Sheridan, and Byron meet). There is no current funding for any of these alternatives and no estimate of if or when it might happen.