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 68Q’s extend well beyond CHOMPImpact to public safety / access to hospital

Operations / Safety at PB GateAcceleration from Holman Hwy to southbound

Hwy 1 entrance rampReduction in crashes and crash severity

Dramatic Emission Reduction - as compared to signal

Operations

2015

Con

trol D

elay

2030

Con

trol D

elay

0

5

10

15

20

25

30

RAB AMSignal AMRAB PMSignal PM

2015 Queue (EB)

2030 Queue (EB)

2015 Queue

(SB Off)

0

200

400

600

800

1000

1200

1400

Interim Signal Alternative2015 + Project PM Peak

660

315

Existing Condition 2015 + Project PM Peak

660

315

Existing Traffic Signal Condition

250’

Existing Traffic Signal Condition

40 MPH

What About Converting the Existing Intersections?

Holman Highway

115/2/2013

Roundabout

Bev

erly M

anor

Holman Highway

Design Optimization-Overlay

125/2/2013

Tighter Radius = Slower Speed,

Slower Speeds = Less Merge Distance Req’d

Less Downstream Merge Distance Req’d

Improved Pedestrian Safety

Improved Entry/View Angle

Longer Merge Distance

Improved Lane Utilization

Separation of Decision Making / Improved Signing and Lane Choice

Design Optimization-Overview

135/2/2013

Improved

Channelization

Improved Entry/View Angle

Separation of Decision Making / Improved Signing and Lane Choice

Design Optimization

145/2/2013

200’75’

Tighter Rad = Slower Speed 125’ merge distance Req’dDefined Intersection

Movements = Simplified Driver Decisions = Safer

Improved Bike Lane Delineation

155/2/2013

Design Optimization – Off Ramp

“Built To Deliver”

Improved View Angles (12 deg.)

Sends Correct Priority Message

Entering Yield to Circulating Traffic

Design Optimization

165/2/2013 “Built To Deliver”

Design Optimization

175/2/2013 “Built To Deliver”

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

Merging Thru Down-Stream Intersection Un-Defined IntersectionVehicular and Bicyclists Safety Concerns

Large RT Radius = Higher Speed

205/2/2013

Longer Merge Distance

Lane Choice/Complexity

Compressed Decision Making Dist.

Difficult to Sign

“Built To Deliver”

Design Optimization - Challenges

Flat Entry Angle

215/2/2013

Very Short Merge Distance

Lane Utilization

Truck/Freight

Concerns

Poor View Angle to Left

Priority Confusion / Merge Behavior

Entry-Circulating Crashes

“Built To Deliver”

Interim Layout