Access Management: An R-CUT Above the Rest

Transcription

1 Access Management: An R-CUT Above the Rest Presented by Cristine Gowland LADOTD District 62

2 What is an R-CUT? Restricted Crossing U-Turn Non-traditional intersection design: Side street traffic right only U-turn to complete left turn or thru movement Signalized or Un-signalized Benefits: Improved safety Increased efficiency AKA a J-Turn or Superstreet

3 Safety: Conflict Point Reduction CONFLICT TYPE CROSSING CONFLICTS MERGING CONFLICTS DIVERGING CONFLICTS TOTAL CONFLICT POINTS TRADITIONAL INTERSECTION R-CUT

4 J-Turn = U-Turn?

5 District 62 R-CUT Examples H : LA 21 at Zinnia /Greenbriar H : US 190 from LA 22 to Lonesome H : LA 21 Bootlegger to 11th H : US 190 Superstreet

6 LA 21 at Zinnia/Greenbriar Urban 4-lane Divided 2015 AADT: 22,238 45MPH Posted Speed Limit Signalized Corridor Multiple Projects & Permits Zinnia/Greenbriar Issues Crashes Delays Complaints Unwarranted Signal Requests Lack of Policy

7 Aerial View of LA 21 Area

8 LA 21 at Zinnia/Greenbriar (2007) Before Widening Project (H )

9 LA 21 at Zinnia/Greenbriar (2011) After Widening Project (H )

10 LA 21 at Zinnia/Greenbriar R-CUT Project Info State Project H completed in August 2012 Constructed channelized median through Zinnia/Greenbriar U-turns north and south with bump-outs designed for school buses and fire trucks No public meetings were conducted DA and DTOE held meetings with local HOA and elected officials

11 LA 21 at Zinnia/Greenbriar After R-CUT State Project H Center Median Control with Curb-and-Paddles No U-Turn Signage

12 LA 21 at Zinnia/Greenbriar Un-signalized R-CUT Intersection Greenbriar Blvd LA 21 Zinnia Dr

13 Drone Footage LA Zinnia/Greenbriar

14 Before & After Crash History LA 21 at Zinnia/Greenbriar Year Right Angle Left Turn Rear End Run off Road Right Turn Sideswipe Other Non- Collision Injury TOTAL * *Note: 2 right angle crashes were coded in 2015, but one was a right turn crash and one was a left turn crash.

15 EDSM IV Project-specific Guidance Recommendations Vary by Roadway Configuration Spacing of Median Openings Waivers to EDSM

16 Our Experiences... Public Involvement

17 Our Experiences... Public Outreach

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19 Our Experiences... Convenience vs Safety Public views this as driving out of their way Public may favor convenience over safety Misconceptions about delays

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21 Our Experiences... Traffic Studies Count What are the existing problems in the study area? Will my design work? How well will my design work? How long will my design work? What alternatives will work? Which alternative will work best and is cost-efficient? What is the best form of traffic control? Do I have safety issues to address? How do I phase construction? How can I phase large-scale improvements?

22 Our Experiences... Effects on Local Development Shopping Center Permitted: 9/2016 Gas Station & Shopping Center Permit In Progress Shopping Center & Restaurant (Phase 1) Permitted: 10/2017 Shopping Center & Restaurant (Full Build) Permit In Progress Starbucks & Dental Clinic Permitted: 8/2016

23 Our Experiences... Bump-out Design H Passenger Vehicle Dimensions = 19 x 7 ~34 passenger vehicles can fit in the bump-out *Designed for a WB-67

24 Our Experiences... Bump-out Design

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26 Our Experiences... Bump-out Design Lowboy vs WB-67 Modify Center Curb to Accommodate Larger Design Vehicles 5 Wide Median

27 Our Experiences... Bump-outs Parking in Bump-outs Educate Law Enforcement & Public Location of Bump-outs

28 Our Experiences... Curbing (Older Project) US Lonesome Road (Tee Intersection) Mandeville, St Tammany Parish *View from Lonesome Road (side street) No Left Turn/One Way Signage Channelized Curb on Mainline Gap In Curbing Tip of Median Yellow Channelized Striping

29 Our Experiences... Curbing (Older Project) US Lonesome Road Mandeville, St Tammany Parish *Aerial View

30 Our Experiences... Curbing (Recent Project) LA Cherokee Rose/Innwoods Covington, St Tammany Parish *View from Inwoods (side street) Center Back-to-Back Curb No Gap In Curbing Yield Line Back-to-Back Curb (between yellow lines) One Way Signage

31 Our Experiences... Curbing (Recent Project) LA Cherokee Rose/Innwoods Covington, St Tammany Parish Yield Lines Back-to-Back Curb (between yellow lines) Back-to-Back Curb (between yellow lines) Center Back-to-Back Curb (between white lines) *Aerial View

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33 Our Experiences... Maintenance Debris Collects Signs Have to be Reinstalled

34 Our Experiences... Signalization Two existing, partially signalized R-CUTS Traditional signal warrants may not apply Signalized based on presence of: Limited sight distance Dual movements Significant delays Excessive queues Safety concerns Other issues

35 US 190 Superstreet Background Information Covington, St Tammany Parish 61,490 ADT in mph, six-lane, divided urban arterial from I-12 to US 190 Business (Median width ~ 65 ) Corridor can be divided into two sections: I-12 to the Abita River Bridge (~ 2 miles) 7 traditional signals 6 U-Turns with yield control Abita River Bridge to US 190 Business (~ 1 mile) 3 full-access, two-way stop controlled intersections (80-90 wide) 3 U-Turns with yield control. Bordered by a signalized corridor to the north & I-12 to the south

36 Project Update: US 190 Superstreet (H ) Study completed in 2010 Project Let in September 2017 Original project modified to accommodate new development Construction includes: Installation of new curbing Relocation of intersections and U-Turns Installation of 15 new signals Upgrade controllers and detection for 2 existing signals Installation of a fiber interconnect with switches for all 17 signals All signals on this section will be 2 phases only

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38 Lessons Learned Public involvement is key to a successful job Efficiency versus safety Traffic studies Impacts to commercial development Design of bump-outs Limiting turning movements with curb/signage Maintenance issues Signalization

39 Questions