River Rouge isn't gone, it's still Ford's largest factory. 6000 people work there. There are 5 plants with the Dearborn Truck facility being the largest. They sold the steel plant to a Russian firm but it too is still there staffed by UAW local 600. Certainly it isn't as much used at it once was but it is still there. One can tour the facility with staff from the Henry Ford Museum. It's the site of the largest "living roof".
Yes, Detroit is a disaster and going through great parts of are are like visiting a ghost town.
John Thornton