Motorists who travel I-675 to I-285 will have noticed major land clearing along the interstate. The project is building a new collector-distributor (CD) system between I-675 and Bouldercrest Road.
Georgia DOT awarded the $90.7 million dollar project in August 2022. The estimated completion is fall 2025.
I-285 at I-675 CD System
The new CD system will be on both I-285 West and East at the I-675 junction. It also ties into the adjacent Bouldercrest Road exit. But what is a CD system? It separates traffic entering and exiting the interstate away from the main lanes. A CD system has separate lanes next to the main line. Their use within the metro area is most prevalent along I-85 in Gwinnett County.
Presently, motorists going from I-675 North to I-285 East enter the interstate and they are immediately in an exit only lane for Bouldercrest. When the new CD system is complete, these motorists will instead be in separate lanes next to the mainline I-285. They will have the choice to either exit to Bouldercrest or merge into 285.
A similar set-up will occur going westbound. Traffic going from Bouldercrest to I-285 West will enter a CD system with motorists bound for 675. From there, cars can continue towards 675 or onto 285.
As an added benefit, CD systems allow a motorist to return to the mainline if they enter it by mistake.
As part of the project, crews must replace the existing Bouldercrest Road bridge over I-285. This is to support changes at the Bouldercrest interchanges. Changes will include a new quadrant ramp from Bouldercrest northbound to I-285 west. This ramp must then pass underneath the bridge.
In addition, there will be two all new bridges — one each going either direction on the collector-distributor system. The bridges will cross a stream in the area. The bridge work contributes to the high project cost.
Georgia DOT first initiated design work for the project in 1999. They resumed it in 2014. Engineering work and right of way acquisition then continued for several years leading up to construction.
The state advertised the project for construction bids in April 2022. They awarded a contract to CW Matthews Contracting in August for $90.7 million. The current contract completion date is October 31, 2025.
Total project costs have been about $125 million. Federal and state transportation funds have paid for the project.
Featured image shows I-285 at I-675 under construction in April 2023. Georgia DOT photo.