Skip to main content

Remaining stretch of I-485 will feature three unique types of interchanges

Image
By
The remaining 5.4 miles of I-485 currently under construction in Mecklenburg County will feature three unique interchanges.  All three are in use elsewhere within the country, but would be the first ones built in the Tar Heel State.

At two of the interchanges, the new designs are considered upgrades (in traffic flow and cost savings) versus what had originally been planned.

The interchange design names are Split Diamond, Diverging Diamond, and Turbine.

Heading East from the current terminus at NC 115, the three new interchange designs run as follows:

The Split Diamond interchange will be located at Prosperity Church Road.  This interchange will consist of two access roads and six roundabouts.

Split Diamond Interchange with Prosperity Church Road (NCDOT)
The Diverging Diamond Interchange (DDI), first used in Missouri, is starting to catch interest in North Carolina.  The interchange design, actually reverses the lanes of traffic on the surface/cross street.  This will be located at the Mallard Creek Road exit on I-485.

This design replaces a planned Single Point Urban Interchange (SPUI) for 485 and Mallard Creek.


We covered a Diverging Diamond Interchange back in October when NCDOT announced it is considering the design on NC 133 where it meets the US 74/76 freeway in Leland.  These two intersections, along with two more on nearby Interstate 85 at NC 73 and Poplar Tent Road, are some of seven prospective locations for this new style of interchange.

Finally, the Turbine - an interchange that has all left turn movements circling around a central bridge in a clockwise direction, creating a seamless movement between the two highways.  This replaces the previously planned four-level stack interchange.  (Similar in design to where I-77 and 485 meet in Southern Mecklenburg County.)

The new "Turbine" interchange at 85/485.  (NCDOT)      
According to NCDOT, this type of interchange will cost less to build and maintain, take up less space, and allow for less interruptions to existing I-85 traffic during construction.


Story Links:
Last Outerbelt juntions to display unique functions ---Charlotte Observer
I-485 Charlotte Outer Loop ---NCDOT
Labels:

Comments

Froggie said…
NCDOT apparently doesn't see it as such, but I-40/Exit 195 (at NC 109) in Winston-Salem, is very much a split-diamond.
9:53 PM
Anonymous said…
Should that be counterclockwise, or am I missing something? (Maybe clockwise in countries that drive on the left...)
11:37 AM
Douglas Andrew Willinger said…
Reminds me of my Alexandria Orb proposal:

http://wwwtripwithinthebeltway.blogspot.com/2007/02/alexandria-orb-page-one-news-december.html

http://wwwtripwithinthebeltway.blogspot.com/search/label/Alexandria%20Orb
8:01 PM
Post a Comment

Popular posts from this blog

North Carolina Continues to Move Forward with Rail

By
2023 and the first half of 2024 have seen continued growth in North Carolina's passenger rail system.  From increased daily trains from Raleigh to Charlotte, federal funds for studying additional corridors, and receiving a historic grant to begin the construction of high-speed rail between Raleigh and Richmond, the last 18 months have been a flurry of activity at NCDOT's Rail Division.  And that's just the tip of the iceberg. As ridership and routes increase - the engine of North Carolina passenger rail trains will become a more common sight. (Adam Prince) Increased Passenger Train Service: On July 10, 2023, a fourth Piedmont round-trip rail service between Raleigh and Charlotte commenced.  The four Piedmont trains plus the daily Carolinian (to Washington, DC, and New York) bring the total of trains serving the two cities daily to five. The current daily Piedmont and Carolinian schedule between Charlotte and Raleigh (NCDOT) The result was over 641,000 passengers utilized pa
Post a Comment
Read more

The Midway Palm and Pine of US Route 99

By
Along modern day California State Route 99 south of Avenue 11 just outside the City limits of Madera one can find the Midway Palm and Pine in the center median of the freeway.  The Midway Palm and Pine denotes the halfway point between the Mexican Border and Oregon State Line on what was US Route 99.  The Midway Palm is intended to represent Southern California whereas the Midway Pine is intended to represent Northern California.  Pictured above the Midway Palm and Pine can be seen from the northbound lanes of the California State Route 99 Freeway.   This blog is part of the larger Gribblenation US Route 99 Page.  For more information pertaining to the other various segments of US Route 99 and it's three-digit child routes check out the link the below. Gribblenation US Route 99 Page The history of the Midway Palm and Pine The true timeframe for when the Midway Palm and Pine (originally a Deadora Cedar Tree) were planted is unknown.  In fact, the origin of the Midway Palm and Pine w
Post a Comment
Read more

US Route 101 in Benbow, Garberville and Redway

By
The communities of Benbow, Garberville and Redway can all be found along US Route 101 within southern Humboldt County.  The former surface alignment of US Route 101 in Garberville and Redway once crossed the Garberville Bluffs along what is now Redwood Drive via a corridor constructed as part of the Redwood Highway during the 1910s.  US Route 101 through Benbow, Garberville and Redway was modernized by 1935.  US Route 101 would eventually be upgraded to freeway standards in Benbow, Garberville and Redway by extension of the Redwood Freeway during 1966-68.  As the cover photo the original grade of US Route 101 and the Redwood Highway can be seen at the Garberville Bluffs during 1934.  US Route 101 can be seen in the communities of Benbow, Garberville and Redway on the 1935 Division of Highways Map of Humboldt County .   The history of US Route 101 in Benbow, Garberville and Redway Benbow, Garberville and Redway lie on the banks of the South Fork Eel River of southern Humboldt County.  D
Post a Comment
Read more