Advancing the Role of Multimodal Accessibility in Transportation Decision-makingITE Mid-Colonial District Meeting

April 14, 2015

Outline

Why accessibility?

Where we’ve been – individual modes / destinations TAZ isochrones

Montgomery bikeshare

Asheville, NC “East of the Riverway”

Where we’re headed – composite / multimodal applications

DC “Healthy by Design”

NCHRP Report 770 (and beyond)

MDOT I-270 Corridor study

Why accessibility?An emerging frame of reference

New Context, Old Tools

Today’s planning context Land use and urban form as variables

Multimodal considerations

Performance based planning

Reinforced by MAP-21 planning emphasis areas

Better tools and measures needed

Multimodal Accessibility

Reflects the D’s: Density,

Diversity,

Design,

D’etc.

Leverages travel time as a universal variable

Is scalable to place and mode

Is conceptually elegant

A Simple but Powerful Framework

6

ACCESSIBILITY =

Land Use

Transportation Network

Opportunities• Number• Variety• Proximity

Travel Time• Connectivity• Directness• Safety

Where we’ve beenAccessibility for individual modes

7

Access to jobs by auto and transit at TAZ level

8

Montgomery Bikeshare

9

Asheville “East of the Riverway”

Historically disenfranchised communities

Reinvestment along industrial riverfront both opportunity and threat

Gridcell analysis focused on walking and transit accessibility

Access to jobs, shopping, health care, and education of interest.

Census and LEHD data associated with hexes based on land use and land cover

Allocation tool was used

Uses Industrial purple

Office red

Retail and services pink

Health care pink

Education blue

Tested a new network of multimodal facilities versus existing

Walk to Employment –Existing Network

Existing Network

Existing Land Use

Walk to Employment –FutureLand Use

Existing Network

Future Land Use

Walk to Employment –Future Network and Land Use

Future Network

Future Land Use

Tested walk access to food markets

Disenfranchised populations are further disadvantaged in terms of accessibility to healthy food

What we need is a new market…

New food market applies land use as a solution to limited accessibility

Asheville Multimodal Network

Where we’re headedTruly multimodal accessibility

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MWCOG/TLC Healthy by Design for Affordable Housing

MWCOG Transportation and Land Use Grant

Locational guidelines for healthy design in affordable housing

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Location & Accessibility

Site & Building Design

Healthy by Design for Affordable Housing

MWCOG/TLC Healthy by Design for Affordable Housing

Identified push and pull factors

Proximity analysis based on 15-20 minute walk

Series of maps by category (e.g. education & childcare, health & social services, jobs, etc.)

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Location & AccessibilityLocating affordable housing in areas with strong walk, bike and transit access to:

• Grocery stores, farmers’ markets, community gardens

• Schools and community centers• Jobs • Social services• Natural spaces and recreational

opportunities• Transit and other non-motorized

options (bike share, car share)

Locating affordable housing away from:• Environmental hazards • Concentrations of liquor stores,

fast food, etc.

Healthy by Design for Affordable Housing

MWCOG/TLC Healthy by Design for Affordable Housing

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Composite mapping to better understand optimal locations for affordable housing

Recommended as policy tool to guide public sector investments

Healthy by Design for Affordable Housing

NCHRP Project 8-78, Report 770

Purpose: Develop responsive tools for estimating bike/walk demand

Outcome: Review of different tools (direct demand and accessibility-based) for forecasting

Springboard: Making accessibility fully multimodal

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Scores Calculated for Each Mode (and purpose)

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AutoTransit Bike Walk

Modal Activity Ranges (defined by speeds)

Starting Point

Travel Time Decay Curve

Accessibility Score =

Σ time-decayed

opportunities

Comparing Accessibility Scores for Different Settings

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Comparing Accessibility Scores for Different Settings

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Accessibility’s Influence on Mode Choice

Logan Circle Clarendon McLean

Auto 4.3 2.3 1.0

Transit 13.6 4.8 1.0

Bike 15.2 3.7 1.0

Walk 38.9 6.9 1.0

Non-motorizedmode share

41% 21% 8%

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Normalized Accessibilities (McLean = 1.0)

MD 355/I-270 Pilot Study Corridor

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Robust multimodal network

Newly adopted Countywide BRT system

Interest in quick-response assessments below the TAZ level

Application of NCHRP 770 concept multimodal

Accessibility Score Calculation

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Accessibility =

𝑂𝑝𝑝𝑜𝑟𝑡𝑢𝑛𝑖𝑡𝑖𝑒𝑠

𝑇𝑟𝑎𝑣𝑒𝑙 𝑇𝑖𝑚𝑒 ∗𝑫𝒆𝒄𝒂𝒚

Where:

Opportunities = Number of Jobs (HBW) or Number of Retail/Service Establishments (HBNW)

Travel Time = Time to reach opportunity over actual network(Network Analyst)

Decay = Factor reflecting decrease in value of opportunities that are farther away

Distance-Decay Relationships (derived from travel survey trip distributions)

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y = 100e-0.07x

R² = 0.9545

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

90.00

100.00

0 10 20 30 40 50 60 70

Per

cen

t o

f T

rip

s w

hic

h a

re L

on

ger

Th

an

Minutes

HBW Walk -- Travel Time Decay

y = 100e-0.088x

R² = 0.9448

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

90.00

100.00

0 20 40 60 80 100 120

Pe

rce

nt

of

Trip

s w

hic

h A

re L

on

ger

Than

Travel time

HBNW Walk -- Travel Time Decay

Calculated for all modes and travel purposesCalculated for all modes and travel purposes

Auto Accessibilities: Work & Non-Work (TAZ)

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Transit Accessibilities: Work & Non-Work (TAZ)

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Walk Accessibilities: Work & Non-Work (Block)

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Bringing Transit Accessibility Down to Block Level

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Decay Factor Applied to

TAZ Transit Accessibility

Score

Transit Walk

Access Time

Work

Travel

Non-Work

Travel

1 min 0.998 0.998

5 min 0.704 0.702

10 min 0.496 0.452

15 min 0.349 0.291

20 min 0.247 0.188

Predicting Mode Shares at Block Level

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Predicting Mode Shares at Block LevelTransit Accessibility: HBW

Transit Mode Share: HBW

Transit Accessibility: HBW Transit Mode Share: HBW

Predicting Mode Shares at Block Level

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Auto HBW

Walk HBW

Auto: HBW Walk: HBW

Comparing MMA Model Estimated Mode Shares by Planning Areawith MWCOG and ACS Household Surveys for Journey‐to‐Work

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Absolute Mode Shares Percentage Differences

ConsideringPlacetypesDefined by Multimodal Accessibility

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Transit MMA LevelW

alk

MM

A L

evel

Land Use & Network Enhancements

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Focus on station areas:• Gude Drive

• Montgomery College

• Edmonston Lane

• Pooks Hill

Effect of Scenarios on Work Mode Shares

Inner circle – existing

Middle circle – BRT improvement only

Outer circle – BRT and enhanced transit oriented development

Effect of Scenarios on Non-Work Mode Shares

Inner circle – existing

Middle circle – BRT improvement only

Outer circle – BRT and enhanced transit oriented development

HBO

Lessons and Observations

Multimodal assessment Common basis of measurement across modes

Strong relationship to observed mode shares

Scalable approach Link between block-level and regional/statewide-level info

Seamless databases emerging nationwide

Access to particular destination types

Benefits to certain population groups

Applicable for a variety of purposes Scenario planning

Project prioritization

Performance measurement

The End