City Council hears engineering report; roundabout proposed at North Jefferson and Dunlap

Milledgeville City Council on Sept. 24 heard a technical presentation from Simonton Engineering on options to address safety and congestion at the North Jefferson Street and Dunlap Road intersection, including a single-lane roundabout, a traffic signal and an all-way stop.

Paul Simonton of Simonton Engineering told the council the firm’s traffic-count analysis and application of the Manual on Uniform Traffic Control Devices (MUTCD) showed crash history (warrant 7) and 70% warrant factors for volume for some signal warrants. "Because this warranted under crash and it warranted under the 70% factor for 1, 2, and 3, this intersection is a really good candidate for improvements," Simonton said.

The consultants presented animations of the existing (no-build) condition, an all-way stop, a mast-arm signal and a roundabout. The no-build scenario produced a level of service E on Dunlap, with long left-turn queues. The signal option produced AM/PM service closer to B in the model but showed stacking on Dunlap; the all-way stop increased queues on Jefferson. The single-lane roundabout produced modeled delays in the A–B range depending on time of day, and the presenters emphasized that roundabouts reduce conflict points.

Corey Johnson described a concept for a standard single-lane roundabout with an approximately 120-foot inscribed diameter that would require limited right-of-way acquisition in the southwest and northwest corners, a truck apron and some restriping to funnel approach lanes. The consultants said grading and drainage improvements would be required and that utility relocations have not yet been fully evaluated.

On cost and schedule, Simonton presented a predesign opinion-of-cost with placeholders for grading, drainage and utility relocation and said roundabout construction traffic control costs can be higher in some line items while long-term operations and maintenance (electricity, signal controller updates and mast-arm maintenance) tend to make signals more expensive to operate over time. Simonton said previous local projects showed a wide range of roundabout costs and that final estimates would depend on site conditions and right-of-way needs. He cautioned that GDOT (Georgia Department of Transportation) funding or review can lengthen the timeline because right-of-way acquisition and the agency’s plan-development process add time; without those delays he said the project could reach construction next spring or summer.

Councilmembers asked about hillside grading at a northwest corner, crash history at a second intersection, utility relocations and the vendor bid environment. Simonton identified Barrister Road as the worst-rated segment in the city’s pavement rating and recommended full-depth reclamation there (grind, stabilize with cement and repave) as part of the LMIG (Local Maintenance and Improvement Grant) program. He said the city’s LMIG package used a DOT rating form across more than 600 roadway sections to prioritize projects and that the city had stacked three years of LMIG funding; the current bid package returned a single bidder, Reuse Construction.

The consultants and staff did not ask the council for an immediate vote on the roundabout or signal; they presented concepts, cost placeholders and next steps including further traffic counts and coordination on utility/drainage work. The council will receive final engineering reports and cost estimates in a future meeting before any formal decision or contract authorization.

Provenance: presentation and Q&A, Simonton Engineering (SEG 232 to SEG 1206).