CHICAGO (AP) — Chicago commuters trying to zigzag around closed streets, diplomatic motorcades and protest zones during this month’s NATO summit could face airport-style security measures on one of the city’s major commuter rail services, officials announced Friday.

With less than a week to go before the May 20-21 gathering, the Metra rail service rolled out a security plan that bars its tens of thousands of passengers from carrying food, liquids or backpacks onto its trains. More than two dozen stations will be closed on the final day of the summit, which falls on a Monday, and stations and platforms will be patrolled by law enforcement personnel and K-9 units.

Adding to the potential for travel headaches, there is a baseball matchup between Chicago’s two teams — the Cubs-White Sox Crosstown Classic — that weekend that could push up passenger numbers. And key roadways, including Lake Shore Drive along Lake Michigan, will be shut down for long stretches.

Starting a day before the summit, Metra riders will be restricted to one small bag about the size of a purse or a briefcase. Luggage, backpacks and bicycles will not be allowed. And passengers may face bag searches or screening before and after boarding.

The agency said it will be forced to close 26 stations along the line running underneath the venue on the final day because it does not have enough staff to provide extra security during a weekday, when ridership is highest. Those stations, on the service’s Metra Electric line, were chosen because they were the least busy.

The line carries around 14,000 riders in from the southern suburbs on an average weekday. “We have a limited amount of manpower with which to accomplish the security screening that must occur through this event,” Clifford said.

Inbound service on the line will be completely shut on May 21 from noon to 6 p.m., around the time delegations are expected to be leaving.

Metra officials would not go into detail about the screening, but they said passengers should allow an extra 15 minutes.

“There will be a variety of methods that we will employ over the three-day period and they will be methods that our customers are accustomed to as they travel in the United States of America,” said Sharon Austin, Metra’s senior corporate director for customer affairs.

Chicago’s other big system, the Chicago Transit Authority, has not announced similar security restrictions, but will have to reroute 24 buses through the summit zone.

Spokesman Brian Steele said the agency is confident its trains can pick up the slack.

“The CTA has extensive experience with this. We do it on daily basis,” he said.

Posted 5/14/2012