"This is a much harder target to hit than it was a year ago"

Boston will pay tribute to the victims and survivors of the bombs that exploded at the marathon finish line one year ago Tuesday. The city is also preparing to protect the marathon route when the 2014 race is run next Monday.

Davis joined "CBS This Morning" to discuss his memories from one year ago and the new security measures that are being implemented to prevent another attack. He told the co-hosts that his deepest memory of the bombing is from his arrival to the scene at the Forum restaurant.

"Seeing the bodies of Lingzi Lu and Martin Richard on the ground and recognizing that these were powerful bombs that were constructed to kill and maim people," he said. "I realized it was terrorism at that moment and I also realized the loss that we were facing."

He said that the Boston Police Department has plans to "increase security dramatically" in order to protect runners and spectators during next week's events.

"Bill Evans, the commissioner of the Boston Police Department, has spearheaded an effort to increase security here dramatically. This is a much harder target to hit than it was a year ago," he said. "There will be three times as many police personnel, undercover people in the crowds, bomb dogs, cameras limiting access to anyone that's carrying anything heavy. This is going to be very tight security scenario."

"That study was completed by Dutch Leonard and his partners at the Kennedy School. They looked at everything that happened. They looked what made us different from other crises that different people have run into," he said. "They really recognized that it was about preparedness and collaboration."

Davis said the planning process was very solid and very structured. There were hospitals nearby, there was rapid and expert medical care.

"The total respect that everyone had for each other made all the difference in the world," he said.

He said one year later the "most important" part of the story is that people of Boston demonstrated "psychological resilience."

"I've gotten to know many of the victims. It is remarkable to see how strong they've become in face of this adversity," said Davis. "People who have had life changing injuries are not only preserving, but thriving. It really is the epitome to this phrase 'Boston Strong'"

The former police commissioner attributed resilience to the sense community in Boston.

"Boston's a tough town. There's a lot that goes on here. There are great people," he said. "It's a big city, but it's a small town in a big city. Everyone seems to know each other.

To see Ed Davis' full interview, watch the video in the player above.