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Multimodal LOS For Urban Streets Richard Dowling – Dowling Associates

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NCHRP 3-70 Research Project y Objective: To develop a scientific basis for evaluating

multimodal LOS on urban streets y 4-year, $1.1 million project y U.S. modal experts y Dr. Aimee Flannery, George Mason University y Dr. Nagui Rouphail, North Carolina State University y Bruce Landis, Sprinkle Consulting y Theo Petritsch, Sprinkle Consulting y Paul Ryus, Kittelson Associates 2


Data Collection y Selected and shot video clips of 90 typical street cross sections

from point of view of auto driver, bicycle rider, and pedestrian. y Showed the clips to 120 people in video labs in four cities. y College Station, Texas y New Haven, Connecticut y San Francisco, California y Chicago, Illinois

y Asked to rate each clip’s

trip experience from “best” to “worst.” 3


What about Transit? y Did on-board surveys in Miami, Baltimore, Portland, and San

Francisco y No matter how bad the service, everybody on board the bus

liked it. y Used mode choice survey results and know patronage

elasticities to construct transit LOS model

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Multimodal LOS Philosophy y Multimodal Level of Service (MMLOS) Analysis for Urban

Streets y Each urban street right-of-way is shared by 4 major types of

users: y Automobile Drivers y Transit Passengers y Bicyclists y Pedestrians

y The urban street should serve all users 5


Definition of MMLOS y MMLOS is the degree to which the urban street design and

operations meets the traveling needs of each user type. y Four level of service grades for each street: y Auto LOS y Transit LOS y Bicycle LOS y Pedestrian LOS

y MMLOS is a

report card. 6

Bancroft Avenue Level of Service User Type AM Pk Hr PM Pk Hr Auto C E Transit B C Bicycle D C Pedestrian C D


Auto LOS – HCM 2000 y LOS by Arterial Class and Speed Threshold Urban Street Class Range of FFS Typical FFS LOS A B C D E F

I 45-55 mph 50 mph

II 35-45 mph 40 mph

III 30-35 mph 35 mph

IV 25-35 mph 30 mph

>42 mph >34-42 >27-34 >21-27 >16-21 <=16

> 35 mph >28-35 >22-28 >17-22 >13-17 <=13

>30 mph >24-30 >18-24 >14-18 >10-14 <=10

>25 mph >19-25 >13-19 >9-13 >7-9 <=7

FFS = Free-Flow Speed 7


Factors Affecting Auto LOS y Number of Stops per Mile y Average speed almost equally as important.

y Stops and speeds are in turn influenced by: y Demand, capacity, posted speed limit, number of lanes, signal

timing, coordination, interference from other users (bus, bike, pedestrian)

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NCHRP 3-70 Auto LOS Model y Probability that driver will perceive LOS “C” or worse

1 Pr( LOS >= C ) = 1 + exp(−α − ∑ β k xk ) k

Parameter

Value

Alpha =

-0.623

Beta (1) =

+0.253

X(1) = Beta (2) = X(2) = 9

Number of Stops/mile -0.3434 Proportion of Intersections with Left Turn Lanes


NCHRP 3-70 Auto LOS Model y Probability that driver will perceive LOS “C” or worse

1 Pr( LOS >= C ) = 1 + exp(−α − ∑ β k xk ) k

With LT lane 0 stops /mi Æ 28% say LOS C or worse 5 stops /mi Æ 57% 10 stops/mi Æ 83%

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Factors Affecting Transit LOS y Frequency of Service y Speed of Service y Passenger Load y Reliability y Accessibility y Bus Stop

Amenities

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Transit LOS Model Transit LOS Score = 6.0 â&#x20AC;&#x201C; 1.50 * TransitWaitRideScore + 0.15 * PedLOS TransitWaitRideScore = fh * fptt

fh

= headway factor

fptt

= the ratio of ridership expected on a route at a headway h, relative to the ridership at 60-minute headways; = perceived travel time factor = the ratio of ridership expected at a perceived travel time rate PTTR, relative to the ridership expected at a baseline travel time rate. The baseline travel time rate is 4 minutes/mile except for central business districts of metropolitan areas with over 5 million population, in which case it is 6 min/mile.

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Converting Transit Scores to LOS y Same as for all modes:

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LOS Model Outputs

LOS Letter Grade

Model <=2.00

A

2.00 < Model <= 2.75

B

2.75 < Model <= 3.50

C

3.50 < Model <= 4.25

D

4.25 < Model <= 5.00

E

Model > 5.00

F


Factors Influencing Pedestrian LOS y Auto Traffic and Speeds, Percent Trucks y Lateral Separation between Vehicles and Pedestrians y Buffers y Barriers

y Crossing Difficulty y At intersections y Mid-block

y Pedestrian Density

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Pedestrian LOS Model y If there is shared use pedestrian/bike path parallel to street: y Then go to shared use path procedures in Chapter 18, HCM

y If no shared use ped/bike path, then Pedestrian LOS is the

worse of: y Pedestrian Density LOS y See Chapter 18, HCM 2000

y Non-Density LOS y The NCHRP 3-70 MMLOS model

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NCHRP 3-70 Pedestrian LOS Model LOS = (0.318 Segment + 0.220 Intersection + 1.606) * (RCDF) RCDF = Roadway Crossing Difficulty Factor

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LOS Model Outputs

LOS Letter Grade

Model <=2.00

A

2.00 < Model <= 2.75

B

2.75 < Model <= 3.50

C

3.50 < Model <= 4.25

D

4.25 < Model <= 5.00

E

Model > 5.00

F


Pedestrian Segment LOS y Function of: y Lateral separation between vehicles and pedestrians y Barriers (trees, bushes, barricades) y On-Street parking

y Presence of sidewalk y Width of sidewalk y Vehicle volumes y Vehicle speeds

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Pedestrian Intersection LOS y Function of: y Right turns on red y Left turns during â&#x20AC;&#x153;Walkâ&#x20AC;? phase y Cross-street vehicle traffic y Cross-street vehicle speeds y Lanes on the cross-street y Vehicle volumes y Vehicle speeds y Delay waiting to cross at signal 18


Ped. Midblock Crossing Difficulty y Can increase or decrease pedestrian LOS by up to 20%. y Factor is related to the minimum of: y Delay waiting for gap in traffic y Delay walking to nearest signalized intersection

y Computation can be turned off.

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Factors Influencing Bicyclist LOS y Auto Traffic y Lateral Separation From Vehicles y Vehicle Speeds y Percent Trucks y Pavement Quality y Driveway Conflicts

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Bicycle LOS Model Bicycle LOS = 0.160*(bicycle segment) + 0.011*(exp(signalized intersection crossing difficulty)) + 0.035*(unsignalized and driveway conflicts) + 2.85

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LOS Model Outputs

LOS Letter Grade

Model <=2.00

A

2.00 < Model <= 2.75

B

2.75 < Model <= 3.50

C

3.50 < Model <= 4.25

D

4.25 < Model <= 5.00

E

Model > 5.00

F


Software Implementation y Now: y Free, unsupported, research quality spreadsheet y Comments welcome

y After June 2010 y If/When included in HCM 2010 update y May be included in some commercial quality, supported software (HCS)

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To Learn More y Final Report: NCHRP Report #616 y http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_rpt_616.pdf

y Userâ&#x20AC;&#x2122;s Guide: NCHRP Web document 128 y http://onlinepubs.trb.org/onlinepubs/nchrp/nchrp_w128.pdf

y For more information or spreadsheet contact: y Kamala Parks, Dowling Associates, Oakland, CA y Phone: 510-839-1742 x 107, kparks@dowlinginc.com

y Rick Dowling, Dowling Associates, Oakland, CA y Phone: 510-839-1742 x 120, rdowling@dowlinginc.com

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2009.Multimodal LOS_Richard Dowling