The CTA viaduct was replaced at Greenleaf Street during the weekend of June 8-10. Trains were stopped in the morning of June 8 to enable workers to remove the old viaduct and make final preparations to install new retaining and foundational walls.
The new viaduct was swung into place at about 7 p.m. on June 9.

In July of 2011 the Chicago Transit Authority Board approved a $10.3 million contract to replace the Purple Line viaducts at Grove, Dempster and Greenleaf streets and to repair the retaining wall along Chicago Avenue from Greenleaf to Hamilton. Funding for the project is provided by an Illinois Department of Transportation grant through the Regional Transportation Authority.

The CTA viaducts are scheduled to be replaced at Dempster and Grove within the next few weeks. Weather permitting, Dempster Street will be closed between Sherman Avenue and Sherman Place for approximately five days, starting June 22.