Also known as a displaced left-turn intersection, these intersections are meant to improve traffic flow, especially for intersections with busy left turns. That being said, continuous flow seems to be a misnomer, as in most, if not all of the cases, none of the traffic in the intersection is “continuously” flowing. As a result, “displaced left-turn” or “crossover left-turn” would appear to be a more accurate term.
Regardless on the name, there are a number of benefits associated with such a design. These include:
- Reduced accidents
- Lower construction cost versus a complete rebuild
- Can take up less land area than other options
- Increased vehicle capacity for both through and left-turn traffic
- Reduced wait times which can also improve energy efficiency
On the downside, there will likely be an adjustment period for drivers that can take awhile. In the interim there can be confusion, frustration, and some accidents resulting from the new design. Given that going against the flow can be counter-intuitive, it is imperative that the signage be clear and concise when the intersection is reopened to help drivers adjust. Public notification campaigns on and through local media and online can be helpful too.
The list below identifies those continuous flow intersections constructed in the United States since the first one was completed in the mid-1990s. Such intersections can be constructed to improve traffic flow in one direction or up to all four directions. To date, the only four-leg continuous flow intersection is located at UT 154 & 4100 South in West Valley City, Utah. In addition, two examples listed below have since been converted into grade-separated interchanges – they are included for informational purposes.
Any updates, additions, corrections, or suggestions are most welcome.
1995
- NJ 168 & Nicholson Road – Philadelphia area (Audubon), NJ – one-leg
1996
- William Floyd Parkway & Dowling College – New York City (Shirley), NY – one-leg
2000
- MD 210 & MD 228 – Washington, DC area – (Accokeek), MD – one-leg
2006
- US 61 (Airline Highway) & LA 3246 – Baton Rouge, LA – two-leg
- UT 154 & UT 173 – Salt Lake City (Taylorsville), UT (since converted to a grade-separated interchange)
- UT 154 & 4700 South – Salt Lake City (Taylorsville), UT – two-leg
2007
- MO 30 & Summit Drive/Gravois Bluffs Boulevard – St. Louis (Fenton), MO – two-leg
- UT 154 & 3500 South – Salt Lake City (West Valley City), UT – two-leg
- UT 154 & 4100 South – Salt Lake City (West Valley City), UT – four-leg
- UT 154 & 3100 South – Salt Lake City (West Valley City), UT – two-leg
2009
- OH 741 & Miamisburg-Springboro Road/Austin Boulevard – Dayton (Miami Township), OH – two-leg
2010
- US 167 & Camellia Boulevard – Lafayette, LA – one-leg
- US 61 & Junkin Drive – Natchez, MS – one-leg
2010
- US 34 & Madison Avenue – Loveland, CO – two-leg
- UT 154 & 7000 South – Salt Lake City (West Jordan), UT – two-leg (since converted to a grade separated interchange)
- UT 154 & 6200 South – Salt Lake City (Taylorsville), UT – two-leg
2011
- Redwood Road & 5400 South – Salt Lake City (Taylorsville), UT – two-leg
2012
- University Parkway & Sandhill Road – Provo (Orem), UT – two-leg
2013
- UT 154 & 13400 South – Salt Lake City (Riverton), UT – two-leg
2014
- US 550 & US 160 – Durango, CO – one-leg
- MD 200 & US 1 – Washington, DC area (Laurel, MD) – one-leg
2015
- MS 6 & Jackson Avenue – Oxford, MS – one-leg
2016
- Quincy Avenue & Gun Club Road – Denver (Aurora), CO – two-leg
- RM 1431 & Ronald Reagan Boulevard/Parmer Lane – Austin (Cedar Park), TX – two-leg
- I-35 Frontage Road & Loop 82 – San Marcos, TX – one-leg
- I-35 Frontage Road & TX 80 – San Marcos, TX – two-leg
2017
- Woodmen Road & Union Boulevard – Colorado Springs, CO – two-leg
- US 19/GA 400 & GA 53 – Atlanta (Dawsonville), GA – two-leg
- OH 125 & Five Mile Road – Cincinnati (Anderson Township), OH – two-leg
2018
- Military Highway & Northampton Boulevard – Norfolk, VA – two-leg
2019
- FL 82 & Daniels Parkway/Gunnery Road – Fort Myers, FL – two-leg
- US 78/GA 10 & GA 124 – Atlanta (Snellville), GA – one-leg
- NC 16 & Mt. Holly-Huntersville Road – Charlotte, NC – two-leg
- Loop 1604 & Bandera Road – San Antonio, TX – two-leg
- VA 190 & Indian River Road – Norfolk (Virginia Beach), VA – two-leg
2021
- Old US 56 & Lone Elm Road – Kansas City (Olathe), KS – two-leg
- US 550 & NM 528 – Albuquerque (Bernalillo), NM – two-leg
2022
- US 85 & Highlands Ranch Parkway – Denver (Highlands Ranch), CO
PLANNED/PROPOSED
- Wadsworth & 38th Avenue – Denver (Wheat Ridge), CO
- Wadsworth & 44th Avenue – Denver (Wheat Ridge), CO
- GA 54 & GA 74 – Atlanta (Peachtree City), GA (2023/24)
- IN 62 & Epworth Road – Evansville (Newburgh), IN
- US 31 & Thompson Road – Indianapolis, IN two-leg (2022) – added 4/30/22
- I-35 & Westinghouse Road – Austin, TX
- Loop 1604 & Culebra Rd – San Antonio, TX
- I-410 & WW White Rd/Cornerway Blvd – San Antonio, TX
- US 281 & Basse Rd – San Antonio, TX
- I-35 & FM 306 – San Antonio, TX
SOURCES:
- Personal knowledge and use of the CFI in Bernalillo, NM
- http://www.maps.google.com
- https://www.ncdot.gov/initiatives-policies/Transportation/safety-mobility/continuous-flow-intersection/Pages/default.aspx
- https://www.ncdot.gov/news/press-releases/Pages/2019/2019-10-14-charlotte-intersection-getting-innovative-pattern.aspx
- https://en.wikipedia.org/wiki/Continuous-flow_intersection
- https://blog.udot.utah.gov/tag/continuous-flow-intersection/
- https://archive.sltrib.com/article.php?id=55293779&itype=CMSID
- https://www.codot.gov/projects/archived-project-sites/us160_us550durangocfi
- https://www.codot.gov/news/2014-news-releases/03-2014/cdot-to-construct-continuous-flow-intersection-in-durango-a-first-on-colorado-s-state-highway-systemhttps://www.thedenverchannel.com/traffic/driving-you-crazy/driving-you-crazy-please-explain-the-confusing-left-lane-turn-set-up-at-quincy-and-gun-club-road
- https://whatsupwheatridge.com/improve-wadsworth?tool=qanda
- https://highlandsranchherald.net/stories/improvements-planned-for-stretch-of-santa-fe-in-highlands-ranch,252209
- https://www.parametrix.com/who-we-are/news/2021/11/23/first-continuous-flow-intersection-in-new-mexico-opens-to-public
- https://www.texashighwayman.com/alt-intersections.shtml
- https://movinghenryforward.org/2020/01/28/gdot-planning-a-displaced-left-hand-turn-intersection-in-peachtree-city/
- https://news.monroelocal.org/georgia-dot-announces-details-on-construction-of-us-78sr-124-continuous-flow-intersection/
- https://www.youtube.com/watch?v=-FZXAAi0LfI
- https://www.fhwa.dot.gov/publications/research/safety/09060/09060.pdf
- https://www.virginiadot.org/projects/hamptonroads/military_highway_continuous_flow_intersection.asp
- https://ftp.dot.state.tx.us/pub/txdot-info/aus/us290/continuous-flow.pdf
- https://www.vbgov.com/government/departments/public-works/roadways/Pages/indian-rvr-kemps-intersection.aspx
- https://www.fhwa.dot.gov/publications/research/safety/09055/index.cfm
- https://www.14news.com/2022/03/10/indot-holds-public-hearing-intersection-project-newburgh/
- http://www.wrtv.com
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