Looking South along Spalding Road (Existing Conditions)
Looking South along Spalding Road (Artist Rending of Options A, B1, & B2)
The intersection of Spalding Drive and Chamblee-Dunwoody Road is a vital gateway into the City of Dunwoody. The intersection is a major decision point for regional commuter traffic from and into residential and commercial areas within the Cities of Dunwoody and Sandy Springs. Additionally, this corridor provides connectivity for reverse-commuting Dunwoody residents to the GA 400 corridor.
The primary objective of the proposed project is to address the City of Dunwoody's safety concerns. Undesirable intersection geometry is the root cause of the safety problems at the intersection. Primary southbound commuting traffic cannot see oncoming traffic from along eastbound Spalding Drive for a sufficient distance to make safe turning and gap decisions. The lack of visibility is due to a combination of vertical and horizontal curves in Spalding Drive. The severe skew of the intersection further limits visibility along the approaches. Given the intersection alignment, a high number of angle crashes occur, which supports the need for a safety improvement at this intersection.
Efficient and safe traffic operations are fundamental project objectives and essential to the success of the project. Strong commuter time of day traffic patterns and intersection geometry both dictate traffic operations at the intersection. Access to and from the side street neighborhoods must be maintained while also accommodating the regional traffic that moves through the intersection. Careful, detailed analysis will be performed to quantify potential benefits of several design alternatives and provide a basis for cost/benefit comparisons between those alternatives.
The City of Dunwoody places emphasis on pedestrian and bicycle safety and connectivity. That goal is embodied in the City of Dunwoody’s Comprehensive Transportation Plan and has been included in every capital project implemented by the City of Dunwoody. Pedestrian safety is the other major safety challenge in the project area. The intersection lacks signalized pedestrian facilities, with no pedestrian signals or push buttons at any crossing.
Looking North on Chamblee Dunwoody Road (Artist rendering of Options A, B1, & B2)
Public Information Meeting
The City held a public information meeting on February 25, 2014 to provide project background, viable intersection concepts, and other project components. City staff presented a brief presentation, and was available immediately afterwards to answer questions and receive the public's feedback. While many design aspects of this project have already been considered, it is still in its early design stages when modifications may be applied. The dialogue between the City and the public is critical to determine the best solution for this and other projects.
These concepts presented at the public meeting are based on input provided by the surrounding neighborhoods as well as traffic and crash data. From on this initial information and feedback, the desired outcome for this infrastructure project will be to improve the safety for both vehicles and pedestrians, traffic operations, and way-finding improvements. Maintaining the character of the neighborhood and minimizing impacts to property owners are additional goals for this project.
Option A is a traditional intersection improvement that would add left turn lanes on the Chamblee Dunwoody and Spalding legs of the intersection. Pedestrian enhancements would include bikelanes and sidewalks would be added along Chamblee Dunwoody Road and Spalding Road as well as signalized pedestrian crossings. The purpose of this particular option would be to maintain the construction entirely within the City of Dunwoody and not require participation from the City of Sandy Springs. However, it would not improve the sight distance issues along Spalding Road. This option would have an approximate cost of $900k.
Option A Traffic Model
Option B1/B2 are also traditional intersection improvements, that would include the safety enhancements of Option A and would also corrects the poor sight distance on Spalding Road. These options would provide southbound Spalding Road drivers the ability to see oncoming northbound traffic so they may determine if there is adequate gap to safely make a left turn onto Chamblee Dunwoody . These options would extend into the City of Sandy Springs and require their participation on this project. Option B2 would extend south on Spalding an appropriate length to also correct the sight issues for drivers wishing to turn onto Spalding Road from Dunwoody Road and Auden Trail. The approximate total cost of this project would be approximately $1.25-1.35M.
Option C, referred to as the "One-Way Trio", is a non-traditional approach to this intersection. This option would create a network of three one-way roads within the triangle created from Spalding Road, Chamblee Dunwoody Road, and Dunwoody Road. It would redirect northbound traffic from Spalding onto Dunwoody Road and then north Chamblee-Dunwoody Road. Likewise travelers approaching the intersection from the south on Chamblee-Dunwoody Road who intend to travel south on Spalding would be required to continue north on Chamblee-Dunwoody to the Spalding to turn south rather than use Dunwoody Road. With this option, all three intersections would need to be reconstructed; however, alterations to the existing lanes would be virtually limited to repaving and restriping the roads to change from two-way to one-way traffic. This option would also extend into the City of Sandy Springs and require their participation. The approximate total cost of this option would be $900k.
Traffic Model - Option C
Conflict Points - This diagram provides a comparison of the vehicle conflict points at each intersection along Option C compared to existing conditions.
(Updated April 8, 2014)