The three big vertical lines are 345-KV power lines on Fermilab site. The corkscrew line is a so-called "static line" that is nominally connected above the HV lines (serves to protect from lightning, I think), but snapped and landed and took one of the three phases to ground. This even knocked out power to all of Fermilab for several hours. It was the second site-wide power outage in an eight hour period.