CR 30 / CR 11 and CR 30 / CR 11C Intersection Improvement Project. What Should We Build?

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1 CR 30 / CR 11 and CR 30 / CR 11C Intersection Improvement Project What Should We Build?

2 Background CR 11 (Timberline) Donath Lake CR 30 CR 11C Stop controlled intersections Currently long delays (several minutes) Level of Service F during rush hour 23 reported crashes at the 2 intersections in the last 3 years. Boyd Lake

3 Federal Funding Application North Front Range Metropolitan Planning Organization (NFR MPO) call for projects 22 projects by 7 entities CR 30 / CR 11 scored the highest of all submittals in terms of issues related to function, capacity, safety etc. $534,000 awarded for improvements (partial funding)

4 What Should Be Built? Turn Lanes and Signals? Single Lane Roundabouts?

5 Roundabouts 101 in 60 seconds..

6 What Is NOT A Roundabout? NO! NO! NO! NO! NO!

7 What Is A Roundabout? YES!

8 Roundabout Terminology Modern Roundabout Yield at entry Deflection at entry Slow speed Circulating Road Yield Line and Entry Central Island including Truck Apron Exit Pedestrian Crosswalk Splitter Island

9 Roundabout vs. Traffic Circles Size is different Speed is different Design is different Traffic circles are being removed, roundabouts are being built More than 2,000 roundabouts in the U.S. Kingston, New York

10 Roundabouts and Safety Conflict Points Signal: 32 Total 16 Crossing Roundabout: 8 Total 0 Crossing on a national level when compared to signals: 40% fewer overall accidents for roundabout 75% fewer injury accidents for roundabout

11 Capacity and Operations No lost time (start up and all-red) Simultaneous entries Easily handles wide variety of volumes Accommodates left turns same as right and through movements Much less idling Works for 5 legged intersections

12 Where to Build A Roundabout Not everywhere! A site specific review is important Good Locations: Similar volumes on all legs Short, concentrated peak volumes High percentage of left turns More than four approach legs High crash locations Bad Locations: Highly unbalanced flows on approaches Topographic / site constraints Very busy intersections where roundabouts cannot provide capacity Isolated intersection in an existing network of signals

13 Miscellaneous Items: Large Vehicles / Trucks Older Drivers (IIHS and AARP support more roundabouts) Bikes / Peds

14 Public Opinion Taft/Vine Roundabout support = 55% Roundabout support = 85% (includes School District and Emergency Services)

15 Roundabouts in Larimer County Taft Hill and Vine Drive (2006) Urban Design Function : F to an A, no delays Total crashes down 11% Severe crashes down 75% CR 30 / CR 9 (2009) Rural Design Function: F to an A, no delays Total crashes down 62% Severe crashes down 38%

16 Back to CR 30.

17 Technical Comparison Signal Function Safety Air Quality Bikes/Peds Trucks Spatial Requirements- Aesthetics Construction neutral neutral neutral Roundabout Cost million 1.3 million

18 Public Outreach and Input Web information Newsletter to area residents Newspaper ad Open house Individual meetings Results: 12 written comments 9 in favor of roundabout 3 in favor of signals

19 Potential Design Refinements for Roundabouts Based on Public Input Minimize impact of lighting requirements (cutoff lighting, less luminaries, etc.) Balance the design speed for rural roundabouts Make sure landscaping maintenance is clear

20 Staff Recommendation Based on technical comparison, and strong public support, Larimer County staff recommends the single lane roundabouts. Considerations should be given for design refinements based on public input.

21 Discussion and Questions for the Board: Is the BCC comfortable moving forward with roundabouts? Or is an alternate approval process needed?