Holman Highway 68 / Highway 1 Roundabout Planning Commission May - PowerPoint PPT Presentation

Holman Highway 68 / Highway 1 Roundabout Planning Commission May 14, 2013

Congestion

Roundabout Project Need  Long Traffic Q’s and excessive delay on E/B Holman Hwy 68  Q’s extend well beyond CHOMP  Impact to public safety / access to hospital  Operations / Safety at PB Gate  Acceleration from Holman Hwy to southbound Hwy 1 entrance ramp  Reduction in crashes and crash severity  Dramatic Emission Reduction - as compared to signal

Operations 1400 30 1200 25 1000 20 800 RAB AM 15 Signal AM 600 RAB PM 10 400 Signal PM 5 200 0 0 2015 2030 2015 2030 2015 Control Control Queue Queue Queue Delay Delay (EB) (EB) (SB Off)

Interim Signal Alternative 2015 + Project PM Peak 660

Existing Condition 2015 + Project PM Peak 660

Existing Traffic Signal Condition

Existing Traffic Signal Condition

What About Converting the Existing Intersections?

Roundabout Holman Highway 5/2/2013 11

Design Optimization-Overlay Beverly Manor Holman Highway 5/2/2013 12

Design Optimization-Overview Tighter Radius = Slower Speed, Slower Speeds = Less Merge Distance Req’d Less Downstream Merge Distance Req’d Longer Merge Distance Improved Pedestrian Safety Improved Lane Utilization Improved Improved Entry/View Angle Channelization Separation of Decision Making / Improved Signing and Lane Choice 5/2/2013 13

Design Optimization Improved Entry/View Angle Separation of Decision Making / Improved Signing and Lane Choice 5/2/2013 14

Design Optimization – Off Ramp Tighter Rad = Slower Speed Defined Intersection 125’ merge distance Req’d Movements = Simplified Driver Decisions = Safer Improved Bike Lane Delineation “Built To Deliver” 5/2/2013 15

Design Optimization Improved View Angles (12 deg.) Sends Correct Priority Message Entering Yield to Circulating Traffic “Built To Deliver” 5/2/2013 16

Design Optimization “Built To Deliver” 5/2/2013 17

The Timing is Right  Pebble Beach Project Approved  Concept Plan Complete  Stakeholders On-Board  Relinquishment In Process

Next Steps  Engineering Design  Project Report Amendment  EIR Addendum  Public Outreach and Education  Construction

Design Optimization - Challenges Large RT Radius = Higher Speed Merging Thru Down- Stream Intersection Un-Defined Intersection Vehicular and Bicyclists Safety Concerns Longer Merge Distance Lane Choice/Complexity Compressed Decision Making Dist. Difficult to Sign “Built To Deliver” 5/2/2013 20

Design Optimization - Challenges Very Short Merge Distance Lane Utilization Truck/Freight Flat Entry Angle Concerns Poor View Angle to Left Priority Confusion / Merge Behavior Entry-Circulating Crashes “Built To Deliver” 5/2/2013 21

Interim Layout