Kentucky s First DCD Interchange: One Year Later SEAUPG Annual Meeting November 13, 2012 Kentucky s First DCD Interchange One Year Later Project Background Project Schedule Post-Construction Findings http://transportation.ky.gov/us-68-double-crossover-diamond Project Location Project Corridor To Downtown 2,000 To Man o War Blvd. 1.High Crash Rate Project Issues 2.Heavy Through Movement on Harrodsburg Road 3.Heavy Left-Turn Movements onto New Circle
Shared-Use Paths Previous Interchange Layout DCD Interchange Layout Project Schedule Public Meeting #1 March 29, 2011 Project Letting May 20, 2011 Public Meeting #2 June 23, 2011 Traffic Pattern Shift August 14, 2011 All Lanes Open October 9, 2011 Construction Complete November 15, 2011
Contract Notes on Maintenance of Traffic Inner Loop Entrance Ramp LANE CLOSURES SHALL NOT BE ALLOWED DURING THE HOURS OF 6:00 AM TO 7:00 PM MONDAY THROUGH FRIDAY TRAFFIC SHALL BE SHIFTED TO THE ULTIMATE CONFIGURATION PRIOR TO AUGUST 31, 2011. LIQUIDATED DAMAGES OF $5000.00/HOUR WILL BE ASSESSED UNTIL THIS HAS OCCURRED. Inner Loop Exit Ramp Outer Loop Exit Ramp Friday, August 12 Saturday, August 13
Opening Morning Monday Morning Rush Hour Project Cost Lesson Learned #1: Unavoidable Conditions Engineer s Estimate: $5.79 M Winning Bid: $5.67 M ATS Construction 4,400 tons of surface 7,825 tons of base Unsuitable subgrade material Difficult to predict Subgrade manipulation not always feasible Lesson Learned #2: Utilities Lesson Learned #3: Contractor Input Subsurface Utility Exploration (SUE) Urban areas Tight constraints Not cleared before construction Contractor Input prior to Letting KY Contractors Association Aggressive schedules
Post-Construction Crash Data* Crash Data Traffic Operations Public Feedback Averaged 10.3 crashes per month from 2008-2011 *Includes all reported crashes between Beaumont Centre Parkway and Alexandria Drive. Crash Data Crash Types Jan. 1 June 30, 2012 We re averaging 45% fewer crashes with the DCD interchange. AM Traffic Pre-DCD AM Traffic Post-DCD Backups well beyond Snaffle Road Backups onto New Circle Road Beaumont Centre completely clears Common backups to Wellington Way Backups rarely extend halfway to Fort Harrods from Corporate Drive Ramps back up mid-way
KYTC Survey: Over 1,400 responses Overall, do you think this project was a good transportation solution for this location? 72% said it was a good solution Do you think a DCD interchange should be considered at other locations in Lexington or elsewhere in Kentucky? Other DCD s under Design in KY KYTC District 6 is designing two DCD s along I-75 in Boone County 72% said a DCD should be considered elsewhere Inner Loop Crossover Inner Loop Crossover
Inner Loop Crossover Inner Loop Crossover Inner Loop Crossover Inner Loop Crossover Contact Information November 2012 Brian Aldridge, P.E. Stantec Consulting Services 10509 Timberwood Circle Suite 100 Louisville, KY 40223 Brian.Aldridge@stantec.com Phone: (502) 212-5000 Jason Bricker, P.E. Stantec Consulting Services 400 East Vine Street Suite 300 Lexington, KY 40507 Jason.Bricker@stantec.com Phone: (859) 233-2100 http://transportation.ky.gov/us-68-double-crossover-diamond
November 2012 Acknowledgements KYTC Central Office Highway Design Jeff Jasper Keith Caudill KYTC District 7 James Ballinger Bob Nunley Steve Farmer Tony McGaha KYTC Central Office Traffic Jeff Wolfe Lynn Witmer Ted Swansegar LFUCG Division of Traffic Steve Cummins Jeff Neal Billy Treadway Joel Weber January 30, 2012 January 30, 2012
PM Traffic Pre-DCD PM Traffic Post-DCD Heavy congestion on Beaumont Centre Parkway Beaumont Centre clears in signal cycle Free flow leftturn lanes reduce congestion Corporate queues for about 35 minutes Heavy congestion for left turns onto New Circle Backups well beyond Larkspur Drive Corporate queues for about 15 minutes Queues to Burbank clear in one signal cycle Crossing Angle I-270 at Dorsett Ave, St. Louis, MO Missouri DOT 40 50 degrees Bicycle and Pedestrian Accommodations Positive Feedback I am writing to commend ENTRAN and the KYTC for their work on the DCD interchange on US 68 in Lexington, KY. information presented at multiple public meetings, on the project website, and through local media outlets helped me understand how the design works and educated countless citizens about the project. The interchange has improved safety, reduced traffic congestion, and made a significant step in connecting Lexington s expanding bicycle and pedestrian network. Lexington-Fayette Urban County Government Councilman Doug Martin
Positive Feedback Typical Sections Beneath New Circle Sadly, I'm hearing the same pessimistic commentary that I did when they were building the Frankfort Pike round-about. Those naysayer's are nowhere to be found now that it's finished and is working like a charm. No one ever said that the "DCD" would cure all the problems at this particular intersection, but rather that it would reduce a significant amount of the rush hour congestion. From what I've observed during its construction and 3 trips through the intersection (one at morning rush hour), this too is destined to achieve what was intended by the design. Read more here: http://www.kentucky.com/2011/08/15/1846182/motoristsnavigate-new-harrodsburg.html#storylink=cpy Typical Sections At Crossovers Curvature & Crossing Angle New Circle Road Outer Loop Exit Ramp Curvature & Crossing Angle
Existing (2007) Existing AM Morning Peak Hour Simulation DCD Existing AM Crash History January 1, 2008 December 31, 2010 484 Reported crashes 388 rear end crashes (80%) 48 Sideswipe crashes (10%) 90 injury crashes (19%) Outer Loop Exit Ramp Outer Loop Exit Ramp
Peak Hour Traffic Counts 2007 AM Peak Hour Counts Peak Hour traffic is 20% to 40% higher than before the project began in 2007. 2007 PM Peak Hour Counts No Turns on Red Expected Oncoming Traffic Actual Oncoming Traffic Source: Missouri s Experience with a Diverging Diamond Interchange, Lessons Learned
Weaving Condition 2006 Congestion Management Study: Tates Creek Rd. at New Circle Rd. Increased capacity 15% - 25% Delay reduced by as much as 65% Two-Phase Signal Operation Two-Phase Signal Operation Left turns are free-flow Conflict Points are Reduced DCD 2 crossing conflict points Conventional 4 crossing conflict points
East of Pasadena Drive I-44 at SR 13, Springfield, MO I-44 at SR 13, Springfield, MO Opened 6/21/09 Cost: $2.9M SR 13-29,000 vehicles per day Crashes decreased by 60% from 2008 4 others have since opened in Missouri Source: http://www.usatoday.com/news/nation/2010-01-27-diverging-diamondinterchange_n.htm Meeting with MoDOT