Utilizing Connected Travel Demand and Land Use Models in

the Sacramento Region

Gordon R. GarrySacramento Area Council of Governments

April 30, 2010

Why improve SACOG models?

• Models are tools to apply research in the most effective and comprehensive manner to address policy issues

• Research points to interrelated causes and consequences

• Policy issues are often, and more frequently, interrelated

MEPLAN - Land Economics to PECAS model

SACSIM activity-based travel model

I-PLACE3S - Land Use/Transportation Impacts

Develop Better Information and Tools for Decision Making

PECAS and I-PLACE3S

• Differences– Economic forecast vs. vision development – Path dependent vs. horizon year

• Common elements– Parcel data– Development policy tools– Development costs and rents

• Partial overlap– Employment types, residential definitions

Conclusions on land use models

• Policy drives data and models • Incremental improvement = continuity • Model development is “pushed” by research

advancements and “pulled” by policy needs• Integrated cross-discipline planning and

decision-making can be improved with good analysis

Overview of Regional Travel Model (SACSIM)

Performance characteristics

A regional analysis example

A land use project analysis example

I-PLACE3S UsesRegional to Neighborhood-level applications

Regional Blueprint Land Use Scenarios

Regional Transportation Plan Public Workshops

• Edit roadway links or roadway projects

• Edit transit routes

Neighborhood Study Area Land Use Scenario

Roseville Fairgrounds

Changes from base case:

700 more employees

400 more dwelling units

- 7 % VMT

74 Acres

Local Land Use Plan Updates

• Two cities used I-PLACE3S to develop General Plan land use scenarios

“Place Types” are the Building Blocks

User-Defined, includes:

• Inventoried allowed land uses

• Land uses that might not yet exist in codes (e.g. mixed use)

New Modules Developed Through King County WA Study

Public health (outcomes: physical activity, BMI, walk and bike trips)

Climate change and air quality (outcomes: CO2, NOx, HC, and CO; vehicle trips and VMT)

Climate Change Module (Household Inputs)

• Household demographics– Working adults– Non-working adults– Children

• Household Income• Access to transit• Area intersection density• Household area density• Area mix of land uses

Physical Activity and BMI Module (Person Inputs)

• Demographics– Number of adults in

household– Employment status– Number of children

in household• Ratio of adults to cars• Household income

• Access to transit • Intersection density• Area housing density• Area land use mix• Park availability• Area retail and fast food

establishments

Demographic Variables

Density & Accessibility Measures

P roduction

E xchange

C onsumption

A llocation

S ystem

PECAS Framework Components

• Economic Interactions (Activity Allocation):• Production to exchange to consumption location chains determined for all goods, services and labor

• Equilibrium markets for all commodities, with prices & clearing• Consumer surplus and producer surplus considered

• Space Development (Land Use):• Changes in space year-to-year based on allowable zoning and prices from Activity Allocation

• Links to:•Travel model (trip-based or tour-based)•Non-spatial economic model

Benefits

• Apply economic analysis to spatial/land use issues• Simulate developer decisions in addition to

government policies• Land use impacts for travel and emissions• Peak spreading of congestion• Pricing policy analysis• Improved impact assessment

Model comparison – Unit of Analysis

• SACMET = TAZ and Trip– TAZ is a geographic area with number of people,

jobs, etc.– Trips are “disembodied” and treated as a

“gravitational” event• SACSIM = Persons and Tours

– Population represents variety of people in a “real” way

– Travel is an outgrowth of activities—a way of stringing activities together

Typical Household’s Travel

Sample home

Central City

Shopping Center

Office

Trip 11

Trip 1,2,3

Trip 4

Trip 7

Trip 8,9,10School

Trip 12

Trip 13

Soccer field Trip 14,15

Trip 16,17

Office

Trip 5

Trip 6

A Practical, Regional Planning Application

• Vehicle miles traveled as primary indicator– Defining area types by average VMT per

household• Land use characteristics of VMT-defined

areas• Drilling down to specifics in prototype areas• Forecasting results

2005 VMT Per Household

2005 VMT Per Household

• 2005 reg. average VMT/HH = +/-50 miles– Dark green = Group 1--Very Low VMT (< 25

miles)

– Light green = Group 2--Low VMT (25 – 45 miles)

– Yellow = Group 3--Average(45-55 miles)

– Orange = Group 4--High (55-75 miles)

– Red = Group 5--Very High (75+ miles)

Density in Prototype Areas

• Density = Jobs + housing per acre at place of residence

• Higher density = lower VMT

28

13

64 3

0

5

10

15

20

25

30

1 Very Low 2 Low 3 Average 4 High 5 Very High

VMT Grouping

Transit Proximity in Prototype Areas

• Proximity = % of households within ¼ mile of nearest transit

• Higher proximity = lower VMT

100%

91%

74%

22%

13%

0%

10%

20%

30%

40%

50%

60%

70%

80%

90%

100%

1 Very Low 2 Low 3 Average 4 High 5 Very High

VMT Grouping

Mix of Use (Diversity) in Prototype Areas

• Mix Index = 0 (homogeneous development) to 100 (balanced mix)

• More balanced mix = lower VMT

66

56

44

23

7

0

10

20

30

40

50

60

70

80

90

100

1 Very Low 2 Low 3 Average 4 High 5 Very High

VMT Grouping

Bike/Walk Mode Share in Prototype Areas

• Regional Average = 7.5 %• Higher share in lower VMT areas

37.4%

19.4%

7.7%5.5%

2.3%

0%

5%

10%

15%

20%

25%

30%

35%

40%

1 Very Low 2 Low 3 Average 4 High 5 Very High

VMT Groupings

Transit Mode Share in Prototype Areas

• Regional Average = 1.2 %• Higher share in lower VMT areas

7.4%

2.8%

1.3%

0.3% 0.1%

0%

1%

2%

3%

4%

5%

6%

7%

8%

1 Very Low 2 Low 3 Average 4 High 5 Very High

VMT Groupings

Curtis Park Village:A Development Project Example

Three Development Options

Project Housing and Employment Information

  Total Housing

Units MF Units

SF Unit

s Comm.

Sq. Ft.Scenario

Developer Option B Plan 594 416 178 170,000

Developer August 2009 Plan 631 337 294 249,000

SCNA Plan 690 446 244 153,500

Project Area Travel Metrics

Year 2035 Weekday Travel Indicators for Curtis Park

Village

 

Develo

per Option

B

Develo

per Aug2009 Plan

SCNA Plan

Project Area Only      

Vehicle Miles Traveled 12,830 17,198 15,343

VMT Per Person+Job 6.7 7.3 7.4

Transit Trips 156 177 202

Transit Mode Share 3.8% 3.5% 4.3%

Bike+Walk Trips 474 591 560

Bike+Walk Mode Share 11.7% 11.7% 11.9%Source: Sacramento Area Council of Governments, October 2009.

Project + Neighborhood Travel Metrics

Year 2035 Weekday Travel Indicators for Curtis Park

Village and Neighborhood Area

 

Developer

Option B

Developer

Aug2009 Plan

SCNA Plan

Expanded Project Area    

Vehicle Miles Traveled 571,499 575,327 571,534

VMT Per Person+Job 16.3 16.2 16.2

Transit Trips 9,909 10,441 9,998

Transit Mode Share 6.3% 6.6% 6.4%

Bike+Walk Trips 13,930 14,135 14,110

Bike+Walk Mode Share 8.9% 9.0% 9.0%Source: Sacramento Area Council of Governments, October 2009.

The Project’s Internal Capture Vehicle Miles vs. External Areas

Year 2035 Weekday VMT To, From, and Within Expanded Project Area

Developer Option B

Developer Aug2009 Plan

SCNA Plan

VMT within Exp.Proj.Area 11,887 12,077 11,960

Diff from Opt.B Na +190 +72

VMT between Exp.Proj.Area and External Areas 559,612 563,250 559,574

Diff from Opt.B na +3,639 -38

Total VMT 571,499 575,327 571,534

Diff from Opt.B na +3,828 +35Source: Sacramento Area Council of Governments, October 2009.