The lights were on Wednesday morning, but overnight storms knocked out the computer system that times them during rush hour periods. The system allows for longer green light cycles to accomodate heavier traffic going in certain directions on certain roads. The outage only affected roads north of the Beltway.
Crews worked all morning and into the afternoon to make sure the lights would be fine for the afternoon rush hour. About half of the 800 traffic lights in the county are timed with the computer system, and the outage affected approximately 200 of them. The county wants to have all 800 lights on the automated system by 2012. When that occurs, a county spokeswoman says large-scale outages like Wednesday morning's should no longer occur.
This outage is different than that of one that occurred two years ago, when the system failed for all roads in the county. That was attributed to a computer error.