Residents who live near the Johnson Ferry Road, Glenridge Drive, and Glenairy Drive intersection said they don’t like proposed accident-reducing solutions that were presented at an open house on Feb. 7.
About 30 residents attended the open house held by Sandy Springs to present concepts that would improve the intersection and reduce accidents. Kristen Westcott, the traffic and transportation manager for the city, said the city has had safety complaints and crashes at the intersection over the years.
Andrew Antweiler with KCI Technologies, the city’s consultant on the project, presented two concepts for the intersection. The first was an improved traffic signal with a realignment of the roads. The second concept would create a roundabout intersection.
Antweiler said the approaches of Johnson Ferry Road and Glenairy Drive are skewed and make it difficult for drivers to see the oncoming traffic as they turn.
Antweiler said the traffic signal is currently set for split phasing. When motorists driving eastbound on Johnson Ferry Road heading straight onto Glenairy Drive, or to make turns, they have a green light, and Glenairy Drive motorists would be stopped. When westbound Glenairy Drive motorists get the green light to drive across the intersection to Johnson Ferry Road or turn onto Glenridge Drive, Johnson Ferry motorists would be stopped by a red light. That results in an additional delay at the intersection.
“From a crash perspective, we have approximately 10 crashes per year, and about 75 percent of those are rear-end crashes, and 12 percent are angle crashes,” Antweiler said.
The accidents are not typically severe, but can be reduced with either concept.
Antweiler said the city tasked KCI Technologies with creating a future-thinking design that would continue to reduce the average delays during peak hours, based on traffic volume projections 20 years into the future, 2045. The traffic signal concept would have an average 30 seconds of delay during the peak morning hour. The roundabout’s delay during that time would be an average of 17 seconds. If the city does nothing, the average delay would be about 77 seconds.
In an interview at the open house, Curt Friedberg, past president of Aberdeen Forest subdivision, said the intersection became more dangerous when concrete barriers, crosswalks, and traffic signals were removed.
As for the possible improvements, Freidberg said the neighbors are concerned that forcing so many cars through a roundabout will create more accidents as motorists won’t slow down.
“As people come off of Johnson Ferry onto Glenridge, they literally go at 25 or 35 miles an hour around those turns, which is exactly what’s going to happen in the roundabout,” Friedberg said.
Antweiler said they designed the roundabout concept with a curve on the approach from Johnson Ferry Road to slow motorists down before they reach the intersection.
Neither of the two options presented were viable, Friedberg said, a sentiment shared by several residents during a Q&A session during the open house.
Friedberg said the intersection has two main problems. Cars are not stopping to make a right turn on red when driving eastbound on Johnson Ferry Road to turn right onto Glenridge Drive. He said they treat it like a yield sign. The odd-shaped geometry of the intersection makes left turns difficult from any direction.
A report from KCI Technologies said that the total construction cost for the improved traffic signal concept would be $2.95 million. The roundabout concept would be more expensive at $3.4 million, but was rated with a better benefit-to-cost ratio because Westcott said roundabouts have a better safety record.
Westcott said the project is not currently funded.
Sandy Springs Public Works Director Marty Martin said this project would take five years, with a year of that dedicated to construction. Before construction starts right-of-way access needs to be secured, and utility relocations completed.
Community members can offer comments on the concepts until Feb. 20. Comments can be submitted online, or be emailed to communications@sandyspringsga.gov. More information about the project can be found on the city’s website.
