The city’s detailed security plan for the 117th running of the Boston Marathon shows the same all-out mobilization of officers, bomb-sniffing dogs and explosives specialists as was in place for last year’s race, an indication that the intensity of security preparedness has remained at a high pitch.
Interviews with law enforcement officials and a Globe review of Boston’s plan to police the race show that state and local authorities this year took extensive measures to protect hundreds of thousands of participants and spectators — including the deployment of air patrols, K-9 units, and more than 1,000 uniformed officers and soldiers along the 26-mile course and the finish line.
In Boston alone, there were 824 officers and civilians scheduled to work on Marathon day. That’s a 6 percent increase from 2012, according to copies of the Boston Police Department’s operational plans obtained by the Globe.
“We’ve done as much as we can. Our aim is not to turn this into a police state,’” said Police Commissioner Edward Davis. “We have to allow commerce to occur. When you sweep an area to make sure there are no explosives, you have to control access to the area. Trying to do that along a 26-mile route is very difficult.’’
“I have an 8-year-old child who was murdered here,’’ Davis said. “We will look at everything we’ve done and make sure we do everything we can in the future. These are soft targets. They’re purposely exploited by people.’’
Dogs swept the area for explosives twice before the first runners crossed the finish line, Davis said. Eleven were assigned — four from the Boston police (the same number as last year) and seven from the MBTA. Boston police have a total of 11 bomb-sniffing dogs, which are deployed in shifts.
“Dogs are not infallible,” Davis said. “With such a crowd, the dog can’t check every individual and package. The bomb was comprised of what’s called a pressure cooker, which seals the top of the device. If there is gunpowder in a sealed unit which isn’t emitting any odors, it may be difficult for a dog to detect.’’
Meanwhile, some other state and local agencies also insisted they had even stronger measures in place this year than they had in past years as they have learned from previous races and refined their plans since the Sept. 11 attacks.
The Massachusetts National Guard said it had 464 soldiers along the course, similar to last year and up from around 400 in 2002.
“Our operational plans have never been as thorough and sophisticated as they are today,” said David Procopio, a spokesman for the Massachusetts State Police.
Former Boston police commissioner Paul F. Evans said it is impossible to prevent a terrorist attack without changing what makes the Boston Marathon the Boston Marathon.
“If you want a secure environment, you don’t have any spectators,’’ Evans said. “And that’s not what Boston is about.’’
Davis noted some security measures are simply impractical: “We consider all options but the problem with metal detectors is that they are only good in areas that are controlled and you can’t control something 26 miles long,” the police commissioner said.
Bags and credentials are checked for spectators in the grandstands where VIPs and special guests sit and access is strictly controlled.
“There is a small area around the grandstand that is controlled. . . . The only people who can get in are credentialed,” Davis said.
“That’s because people like the governor and mayor are coming in there. It is a zone set up with increased security. . . . If we tried to do the same thing across the street, all of the businesses would have to shut down.”
The Boston bombing is prompting other road races around the country to rethink their own security plans for future races, even as some of them already have taken steps to lock down access to key portions of the race route.
Organizers of the London Marathon, like Boston among the premier running events around the world, vowed to go on with the race on Sunday – but with extra security. The marathon, which passes by such iconic landmarks as Buckingham Palace, is expected to draw 36,500 runners and 700,000 spectators.
“The race will be going ahead and we will be deploying extra resources as are necessary,” said Nick Bitel, chief executive of the London Marathon.
The New York City Marathon concludes inside Central Park, and race organizers convert the finish area into a secure zone. Nonrunners must have tickets or credentials to enter the areas immediately surrounding the finish line, and all bags are checked.
Other security precautions taken by New York City include a contained start at Fort Wadsworth on Staten Island that requires credentials or a race number for admittance. The baggage that marathoners use for extra clothing are made of clear plastic, and all items inside must be visible for security reasons. The clear bags and other heightened security measures around the start and finish were put in place following the Sept. 11, 2001, attacks.
“9/11 was a game changer in how we approached all security elements across the marathon,” said Mary Wittenberg, chief executive of New York Road Runners which organizes the New York Marathon. “Every year, we’re always adjusting and improving. Now, we go back again.’’
The next major running event on the Boston-area race calendar is the James Joyce Ramble, a 10K that will take place in Dedham on April 28. Even before the Boston Marathon bombings, Ramble organizers had planned to have increased security at its postrace party, and now they are considering more security measures along the course.
What happened in Boston “was certainly why I didn’t have any sleep at all,” said Martin Hanley, founder and managing director of the event. “We are going to try and make everybody safe.’’Todd Wallack, Jonathan Saltzman and Thomas Farragher of the Globe staff contributed to this report.