Proposed safety solutions for ‘killer corners’ intersection require trade-offs

Decatur, GA — The city of Decatur and contractor AECOM held a meeting at North Decatur Presbyterian Church on June 21 to present a number of possible safety improvements to the intersection of North Decatur Road. and Superior Avenue, and along the corridor from Medlock Road to Clairmont Road.
Possibilities include a “no build” approach with sidewalk and crosswalk improvements but lanes remaining the same, a road diet that would reduce the number of lanes to three and add a multi-use path for pedestrians and cyclists, and another version of the road diet that adds improved capacity on Scott Boulevard to include two turn lanes. Two other possibilities incorporate imbalanced lanes, meaning two eastbound lanes and one westbound lane. One would also include dual turn lanes on Scott, and one would not.
Proposals for Superior and North Decatur, nicknamed “killer corners” by some residents due to the high number of crashes there, include a single-lane roundabout and a hybrid, multi-lane roundabout. AECOM associate vice president and program director Dwayne Tedder said that roundabouts have been shown to significantly reduce crashes.
All the designs have trade-offs between safety, effects on traffic, and cost.
Road diets improve safety considerably. AECOM Project Manager Mickey O’Brien said that road diets reduce crashes between 19%-45%. Road diets can also slow traffic considerably, but adding capacity through an additional turn lane can mitigate the problem.
Predictably, the solutions that offer both the most improvement in safety combined with improvements in traffic are also the most expensive.
A road diet combined with dual turn lanes on Scott is estimated to cost $9.2 million, versus $8.2 million for improving the existing four-lane configuration. A single-lane roundabout at Superior is estimated at $7.7 million, while a hybrid multi-lane roundabout would be $10.2 million.
“There’s a real tension there,” Decatur city Engineer Cara Scharer said, a little ruefully. “If it were easy if there were a straightforward solution, it would have been done already.”
Resident Valerie Maier, who lives on Desmond Drive nearby, says that the city could have made more immediate improvements to the North Decatur and Superior intersection with signage and traffic-calming measures to slow approaching cars. Maier fears that whatever the city decides to do will take so long that she’ll never see it completed.
“I’m 70. I don’t think I’ll live to be 100,” Maier said.
Aside from the complexities of traffic engineering, the project will require cooperation between the city of Decatur and DeKalb County while taking MARTA’s plans for the North Decatur corridor into consideration as well.
“This process started from accidents that took place and requests from a variety of neighborhoods, including city neighborhoods and county neighborhoods,” said Deputy City Manager David Junger. “We will be seeking a collaboration with DeKalb on any solution that we come up with. You can see by looking at the map that the city can’t do this alone.”
To see a version of the slideshow from the June 21 meeting about safety improvements on North Decatur Road, click here.
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