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Sunday's time change could pose traffic problems

STAMFORD, Conn. --Sunday's early switch to daylight-saving time is forcing state workers to manually fix hundreds of traffic signals that are programmed to make the switch on the traditional first Sunday of April.

Ignoring the switch could result in traffic signals being off by an hour, possibly gridlocking dozens of communities, the state Department of Transportation said.

"It's a difficult problem that's expensive and time-consuming because we have to go out to all the signals with a replacement program," said Jack Carey, DOT's manager of traffic engineering.

Most computers and electronics built before 2005 are programmed with daylight-saving time starting on the first Sunday in April and ending the final Sunday in October. Those rules, in place for two decades, were overturned by a 2005 U.S. law that extended daylight-saving time by three weeks in the spring and one week in the autumn.

Connecticut officials didn't foresee any problems when Congress passed the law, but are now checking hundreds of intersections to make sure traffic signals are operating in the same time frame, Carey said.

Problems would be most notable in signals that switch to flashing warning lights from 10 p.m. to 6 a.m. When daylight-saving time advances the clocks an hour, unaltered would still be flashing until 7 a.m. and disrupt the early rush hour.

Other lights are time to stay red or green longer based on the time of day. A light at a major intersection may stay green longer during the evening rush to prevent backups, so daylight-saving time could cause a slowdown if the timing is off, Carey said.

The state controls about 2,500 traffic signals. Many are set from a central computer system operated by the DOT, but about 900 need to be manually changed by state employees.

The state has ordered new timers, which collectively cost about $1 million, for those signals. Carey expects they will be installed before 2 a.m. Sunday.

Other transit systems are expecting a smooth transition this weekend.

Amtrak trains will run as scheduled and their on-time performance will be adjusted at the end of the month to account for the hour lost during daylight-saving time, Amtrak spokeswoman Karina Romero said.

All of Metro-North Railroad's clocks and timing devices are connected to an atomic clock in Bethesda, Md., that should automatically reset at 2 a.m. Sunday, said Dan Brucker, railroad spokesman.

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Information from: The Advocate, http://www.stamfordadvocate.com

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