The growing costs and endless frustration of excruciatingly long traffic jams prompted state officials in 2011 to adopt a new plan to deal with interstate wrecks.

Its goal: clear all traffic incidents within 90 minutes. That’s urgent, the “Open Roads” plan said, to restore normal traffic flow. State officials knew that accidents were one of the biggest contributors in more than half of all traffic congestion in metro Atlanta, stunting the area’s growth.

Just as pressing: preventing ripple-effect crashes that are part of the cascading calamity when the region’s already taxed transportation system has a breakdown.

Improving coordination among state and local agencies, wrecker services and emergency workers was key to unclogging jams.

The limitation of that plan, however, was on full display Thursday morning when a pedestrian was struck and killed on I-285 in Sandy Springs. That single event ended up shutting down the interstate for miles and snarling traffic on much of the north side for more than three hours at the height of the morning commute.

Response to these accidents often still falls to local agencies, and many have not signed on to the state plan — or didn’t even know about it. Sandy Springs is one that hasn’t signed on, the Georgia Department of Transportation said. That can lead to scattershot coordination among multiple agencies affected by interstate shutdowns.

Mayor Rusty Paul said nothing would have helped his city respond better to such a gruesome scene. The victim was struck repeatedly, police said, and her remains had to be documented and collected along a quarter-mile stretch of the interstate. As of Friday, police still haven’t determined why Gayla Joyce Walker, 53, was on I-285.

“I cannot emphasize enough, this was anything other than your normal accident,” Paul said. “And if you try to apply the normal procedures to this situation, they just simply don’t apply.”

Still, an angry public vented their displeasure on social media. State officials know there is still work to be done as they have made a renewed push in recent months to sign up more local agencies.

“It’s important,” said Mike Roberson, a GDOT official who co-chairs the Metro Atlanta TIME Task Force. It oversees various training and coordination efforts among local agencies, including the Open Roads plan.

Roberson said there have been successes that he attributes to Open Roads as well as to other task force initiatives. For example, in 2008, the average time for clearing major tractor-trailer incidents on the interstate exceeded four hours. The latest data showed a clearance rate at around 90 minutes.

He said agencies adopting an “Open Roads mindset” has helped.

“There is a benefit to all of these tools,” he said. “If you look at all those as a sum total, there has been a major benefit for our region.”

In the case of Thursday’s incident, however, an Atlanta Journal-Constitution review found gaps in coordination among agencies.

GDOT said it didn’t find out that westbound lanes of I-285 had been closed until one of its own units arrived at the scene. That roadside assistance unit reported at 6:52 a.m. that someone had been killed.

What’s more, by state law, police agencies are required to notify the county’s coroner or medical examiner as soon as they know a person has been killed in traffic. But the Fulton County Medical Examiner’s Office said it wasn’t summoned until about an hour and 15 minutes after the first 911 call.

Paul, the Sandy Springs mayor, said the initial emergency call reported a dead animal in the roadway. Later, police found a shoe and a cell phone, he said.

“As soon as they realized what they were dealing with, then they placed the call to the examiner to get out there,” said Paul, speaking by phone Friday from a mayors’ conference in Washington, D.C.

His account doesn’t line up with other reports from Thursday morning, however.

The Sandy Springs Police Department told WSB’s Traffic Center at 6:50 a.m. that it had confirmed a pedestrian fatality.

The medical examiner’s office says it didn’t get a call from Sandy Springs until 7:30 a.m.

The mayor said he doubted that calling the medical examiner any earlier would have made a difference in how quickly the interstate was re-opened.

But medical examiners do independent investigations, and a body is not supposed to be removed until they consent. An early draft of the Open Roads policy from 2007, explicitly outlines the urgency to call the coroner or medical examiner to ensure the roads are reopened as quickly as possible.

The horrific scene Thursday is testament to why medical examiners need to be on the scene as soon as possible, said Betty Honey, an investigator with the Fulton County Medical Examiner’s Office.

“It’s not like this person got hit and was laying in one piece,” she said. “The investigator had to go and actually look for different body parts and things to get this person, because this person was that badly mangled up from being hit by several vehicles. So something like that takes a while.”

She said law enforcement agencies, however, tend to call the medical examiner as an “afterthought.”

“Because we’ve actually had them call and say, ‘We’re ready for you to come and pick up the body,’” she said. “Well, we do more than that. They’re not supposed to disturb the scene. They’re not supposed to move anything. Everything’s supposed to stay the way it is until we get there and take our pictures.”

John O’Laughlin is a former highway patrol fatality investigator and a national consultant who has advised Georgia’s TIME Task Force. He called a three-hour shutdown for such a terrible scene “excellent,” based on what he’s heard.

“The challenges with that many agencies involved have been overcome probably better in the Atlanta area than anywhere else in the nation,” O’Laughlin said. “It’s unfortunate they didn’t make that call a little sooner, but I can certainly understand, given the totality of what was on that scene, why that occurred.”

For commuters frustrated by what happened Thursday, O’Laughlin said the “Atlanta region does as good if not a better a job on this type of situation than any city in the nation. And it’s because of that TIME Task Force.”

Still, trying to coordinate so many agencies into a coordinate response presents challenges.

“Is there push-back from local agencies? Of course there is,” O’Laughlin said. “That’s human nature. Because it’s their jurisdiction and they want to call their own shots on how they do business.”

He also said not to underestimate the trauma that police officers themselves were experiencing Thursday at the scene.

Chamblee Police Chief Donny Williams agreed and said that can have an impact as officers work.

He also said that Sandy Springs police called Chamblee to let them know they had closed the lanes, and that they’re pretty good about that. Chamblee has no interstates, but Peachtree Industrial Boulevard and Buford Highway which run through Chamblee were both backed up because of the I-285 investigation.

As for the Open Roads policy, Williams had never heard of it until last month. He’s notified the city that the police department will be signing on, and he thinks it’s going to help. On surface roads, “If fire or police are the ones [making the call on lane closures] they have their own way of doing things,” Williams said. “It’s always a thing. We say, ‘Can we open up one lane?’ and they say ‘Nope.’ ”

“You hope that signing it and actually doing something that actually makes a lasting effect — you hope those two things both happen.”

Every minute counts with blocking lanes, he said: “What happens is so quick, the backup and how it affects all the other roads that flow into where you’re at. That can make a big difference.”

The Atlanta Regional Commission sees limiting the impact of these types of incidents as a critical issue for the metro area. In March 2012, the commission passed a resolution supporting Open Roads, and this past week’s event underscored the importance of broad participation, said John Orr, division manager for transportation.

“It’s a key quality of life issue in the region,” he said. “It’s addressing these incidents in a timely manner from an economic impact to a public safety impact as well.”