I asked the "top" four ISP's, and none reported any problems nor any other affects due to the power outage. None reported any power loss at all.
The Internet performance graphs at Matrix shows the world-wide packet loss for the Internet and WWW sites doubled at the time of the Chicago Loop lost power. The packet loss increased from about 3.9% to 7.9%. http://average.miq.net/
The power anomaly (aka blackout) began at 12:45 CDT when a circuit breaker exploded at the 828 S Jefferson Street Commonwealth Edison power station, the resulting fire also damaged other breakers in the station. Power was interrupted between 24th and Chicago Ave; and Lake Shore Drive and Ashland Ave. Power was fully restored shortly after 6pm CDT. I believe this is the same substation which had problems last year. The Associated Press reported 12,000 direct customers were affected.
The Chicago Tribune has a picture of the substation and fire on their web site.
http://www.chicagotribune.com/news/metro/chicago/article/0,2669,ART-47366,FF...
FYI, it wasn't the same substation.... The one last year that was causing the problems was at California and Addison. At the time, I worked at a company that was also at California and Addison, which had their north parking lot seperated from the substation by a fence. For weeks after the big event, fire trucks were there 24 hours a day spraying water on the overheated transformers, to prevent the remaining transformers from dying. For today's outage, ComEd is blaming some automatic fallover system that's made by General Electric for not being able to cut off the failed transformer automatically. I'm currently about 30 miles north of the loop... at 12:46 the voltage coming into the building here was 140-160 volts for several minutes(according to our UPS). I'm wondering if the power was just going nuts everywhere else, causing ameritech equipment to go nuts. Possible explaination for packet loss? I know TCI/AT&T had problems with cable service in the downtown area today. I don't know if their @Home service was affected. -- Kevin