A crane accident at a downtown construction site Saturday led to the evacuation of several buildings and forced the Chicago Transit Authority to reroute trains and buses.
The incident happened when a section of the street under the yellow crane collapsed, causing the massive piece of equipment to lean against the side of a nearby building.
Authorities evacuated buildings near the scene as a precaution because it was unclear how the crane would react when workers try to upright it, officials said.
''All we're worried about now is public safety, so we're making sure everybody is away when we go to do this,'' Fire Chief Mike Fox told WLS-TV in Chicago.
The CTA was forced to reroute service in the Loop on a busy afternoon as a result of the accident.
Not the best picture, but space is kind of tight.
As a note - in this are of the city "ground level" isn't really ground level - the original ground level is about 8-10 feet (call it 3 meters) lower. In the late 19th Century they jacked up entire blocks of buildings, built foundations underneath, and relaid the streets. But underneath isn't solid - it's hollow and they're called "vaulted sidewalks" and such. Many of these spaces are used for storage, among other things.
The point is - this is NOT solid ground the crane was put on, but a construct with very large voids. Construction is largely metal frame and brick-and-mortar (old fashioned red brick, in most cases). Although most in Chicago don't think about this constantly, it's in no way a secret, either. As I said, a lot of business use the spaces underneath for storage. LOTS of people know about these... but apparently not the contractor hired in this case. Or else he/she/they knew, but failed to take into account that the carrying capacity of a 19th Century structure may not have been able to take the weight of the crane.
