WEST ALLIS - Demolition begins Friday night on the Greenfield Avenue Bridge over I-894. The Department of Transportation will rebuild it and make it wider as part of the massive Zoo Interchange reconstruction. I-894 will be shut down completely Friday night into Saturday while the demolition is underway. Some neighbors are concerned about sleeping during the demolition over the weekend. Others say traffic has increased considerably on side streets since Wednesday when the Greenfield Avenue bridge was closed traffic. This project is expected to last until August.