The project team is working with MARTA to provide BRT on the corridor; however, to allow for a future potential northern rail expansion, the concept specifically incorporates design elements to not preclude the potential for future heavy rail transit. To request additional transit related information, please email MARTA at: connect400@itsmarta.com.
Existing SR 400 has generally four non-tolled general purpose lanes in each direction from MARTA North Springs Station to McFarland Parkway and three general purpose lanes north of McFarland Parkway.
The SR 400 Express Lanes project would add two priced express lanes in each direction from MARTA North Springs Station to McGinnis Ferry and one priced express lane in each direction from McGinnis Ferry to just north of McFarland Parkway. Additional lanes are required intermittently along the corridor for either general purpose or express lane access points or for potential queuing BRT stations as well as the collector-distributor lanes. Within the SR 400 Express Lanes project limits and upon project completion, SR 400, in general, will have between eight and 10 travel lanes in each direction (express lanes, collector-distributor lanes, and general purpose lanes). Although in some locations the number of lanes increases to allow for access ramps and connections to other roadway facilities, for example connecting to I-285 near the North Springs MARTA Station and to allow for BRT access to MARTA’s Windward Parkway Park-and-Ride.
Building rail stations and providing transit services are not in Georgia DOT’s purview as a state highways and bridges agency. This request for additional MARTA service has been provided to the MARTA team for their evaluation. To request additional transit related information, please email MARTA at: connect400@itsmarta.com.
In coordination with the City of Alpharetta, Encore Parkway has been determined to not be a viable direct access point location. There are currently proposed direct merge/slip ramps within .5 mile of Haynes Bridge Road that will provide motorists the choice to access the express lanes. Encore Parkway was designed as a gateway signature project to include a pedestrian friendly concept and is wide enough to allow the express lanes to pass underneath the existing bridge.
· In addition to Abernathy Road being outside the limits of this project and as stated above, it is GDOT’s general practice not to consider general purpose interchanges for arterial access ramps to express lanes. General purpose and express lane interchanges remain as separate facilities to avoid potential operational impacts of combining both traffic types into a single location. We are forwarding this comment to the I-285 Top End Express Lanes project team, which is evaluating possible access points between I-285 and SR 400 south of the North Springs MARTA Station.
· As currently proposed, motorists in north Sandy Springs may enter and exit the express lanes system within one mile north or south of the Northridge Road where there is a direct merge/slip ramp access between the general purpose lanes and express lanes. These express lanes access points would allow the drivers to enter the system and to transfer from Sandy Springs into the express lanes network along I-285 as well as the collector-distributor (CD) lane system being constructed under the Transform 285/400 Interchange project that is currently under construction.
· Spalding Drive was considered as an access point in early planning studies. Through further evaluation, the North Springs MARTA Station was selected as the access point for this area. An express lanes access point is not proposed at Spalding Drive; however, there is a proposed direct merge/slip ramp access point, near Spalding Drive.
Previous analysis showed the need for one lane of additional capacity on SR 400 in the segment north of McFarland Parkway. This need has been addressed by the recently constructed third general purpose lane in both northbound and southbound directions as part of the Forsyth County SR 400 capacity adding project. The third general purpose lane begins immediately north of McFarland Parkway and extends north of SR 20. Traffic patterns show that there is a congestion drop off at McFarland Parkway and the recently constructed third general purpose lane has further relieved traffic volumes.
While MARTA service does not extend into Forsyth County, the express lanes would be used by Xpress buses with origins and destinations in Forsyth County.
Roswell is a large city within the project corridor, and in order to provide regional connectivity, increased mobility, and more reliable trip times to Roswell residents, an express lanes access point has been under evaluation through ongoing coordination with the City of Roswell’s staff and elected officials. Close coordination is being conducted with these individuals while balancing the need to meet express lanes demand in Roswell to arrive at a most feasible and efficient express lanes access solution within the City of Roswell.
As part of this project, potential traffic impacts related to this express lane access point will be further studied within the confines of GDOT’s Intersection Control Evaluation (ICE) policy.
It is GDOT’s practice not to consider general purpose interchanges for arterial access ramps to express lanes. General purpose and express lanes interchanges remain as separate facilities to avoid potential operational impacts of combining both traffic types into a single location. As a result, GDOT is not considering Mansell Road, as well as other general purpose access points as potential express lane access points.
As part of this project, express lane access points are being studied. The project team has been coordinating with the City of Roswell on access to the express lane system. The City of Roswell originally proposed Big Creek as an overpass without SR 400 access. To remain consistent with the original intent and citizen understanding of the City of Roswell’s Big Creek Parkway project, through coordination between GDOT and City of Roswell, an express lanes access point was removed from consideration at Big Creek. Based on this, in order to incorporate a direct access point for express lanes users in Roswell, the current proposed design is to place the access point for the City of Roswell south of Holcomb Bridge Road.