Title: Presentation Outline
1(No Transcript)
2Presentation Outline
- Project Purpose and Approach
- Review of Existing Modeling Practice in
California - Methods for Improving Sensitivity to Smart-Growth
Strategies - Conclusions and Recommendations
3- Project Purpose and Approach
4Motivation for Project
- Continued growth is increasing congestion
- There is interest in Smart Growth
- Local jurisdictions need to be able to evaluate
strategies - Local models may not have adequate sensitivity
5Purpose of Project
- Examine how local modeling is being done in
California - Assess how sensitive local models are to Smart
Growth - Identify what supplemental methods are being used
- Prepare recommendations for how to
improveSmart-Growth sensitivity
6Smart Growth Strategies
- Create Range of Housing
- Create Walkable Neighborhoods
- Mix Appropriate Land Uses
- Provide a Variety of Transportation Choices
- Direct Development Towards Existing Communities
- Take Advantage of Compact Building Design
7Desired Smart-Growth Effects
- Providing opportunities to satisfy travel needs
at nearby destinations with shorter vehicle
trips, trip chaining or non-motorized travel - Using land use to create trips with
origin-destination pairs that are more easily
traveled by alternative modes - Providing better and more attractive conditions
for travel by alternative modes - Providing economic incentives for use of
alternative modes
8Project Approach
- Literature Review
- Conventional Transportation Modeling, Local
Models, Smart-Growth Sensitive Methods - Survey of Local Jurisdiction Practice
- Case Study of Six Local Jurisdictions
- Sensitivity Test of Supplemental Method 4D
Elasticities - Formulation of Conclusions and Recommendations
9- Review of Existing Modeling Practice in California
10Uses of Models in Local Land-Use and
Transportation Planning
- Visioning/Policy Development
- General Plan or Specific Plan
- Transportation Investment Study/Corridor Study
- Traffic Impact or Development Fee Program
- Traffic Impact Analysis/CEQA Analysis for New
Development
11Urban Transportation Modeling System (UTMS)
- Use in local modeling is almost universal
- Often referred to as the Four-Step Model
Generation, Distribution, Mode Choice and
Assignment - Trip-based
- Network-based
- Zonal representation of trip makers
12Common UTMS Limitations Affecting Smart-Growth
Sensitivity
- Trips not related
- Consideration of only vehicle trips
- No modeling of walking and bicycling
- Fixed vehicle trip rates by land use type
- Land use not affected by travel patterns
- Design not reflected in choice
- Zonal aggregation of decision makers
- Focus on peak-period travel
- Zones often too large
13Common Practice by Local Jurisdictions
- In area with large MPO SANDAG, SCAG, MTC, SACOG
- Usually a focused version of MPO model
- May also be a focused version of County (CMA)
model - MPO models multimodal and include non-motorized
modes - Local models may not carry all functions of MPO
model - In area with medium MPO
- Often the same model
- Usually includes mode choice
- In area with small MPO or no MPO
- Often most basic UTMS vehicle-trip model
14- Methods for Improving Sensitivity to Smart-Growth
Strategies
15Methods for Increasing Smart-Growth Sensitivity
- Enhancement of UTMS Models
- Activity-Based Travel Models
- Fully Integrated Land Use and Transportation
Models - Application of Smart-Growth Trip and VMT
Elasticities (4Ds) Estimated from Aggregate Zonal
Data
16UMTS Improvement Options
- Income Stratification
- Disaggregate Simulation of Households
- Activity-based Modeling
- Integrated Transportation-Land Use Modeling
- Smaller Zones
- Mode Choice
- Non-Motorized Modes in Mode Choice
- Modeling Multiple Modes of Access to Transit
- Distribution Sensitive to Multi-Modal Options
- Auto Ownership Sensitive to Land-Use
17Logical Progression of Steps to Improve UTMS
Sensitivity
184D Elasticities
- Density population and employment per square
mile - Diversity ratio of jobs to housing
- Design pedestrian environment variables
including street grid density, sidewalk
completeness and route directness - Destination (Accessibility) mean travel time to
all other destinations with a region - 5th D Distance Distance to rail transit
194D Elasticity Values
Source Criterion Planners/Engineers With Fehr
Peers Associates, October 2001.
20Sensitivity Test of 4D Elasticities
- Demonstrated reduction in vehicle trips and VMT
from Smart-Growth strategies - Changes in transit service had no effect on 4D
results - Sophisticated UTMS modeling methods capture most
of the 4D effects
214D Experience in California
- Software options
- GIS-based planning packages INDEX and PLACE3S
- Post Processor to UTMS Model
- Applications
- INDEX Fresno and Madera Councils of Government,
City of Sacramento, Sacramento County, San Luis
Obispo County - PLACE3S Sacramento Region
- UTMS Post Processor Sacramento Region, Contra
Costa County, Humboldt County, Development
Proposals
22- Conclusions and Recommendations
23Conclusions Local Model Sensitivity to Smart
Growth Strategies
- Many local jurisdictions use models that have
almost no sensitivity to Smart-Growth strategies - Local jurisdictions using MPO or CMA models with
more sophisticated features capture some of the
Smart-Growth sensitivity but it is not clear how
much is captured - GIS systems making more sensitivity possible
24Conclusions Supplemental Methods
- 4D elasticities capture some of the Smart-Growth
sensitivity but not all - The 4D elasticities capture some unknown
trip-reduction effects as a result of correlation - The 4D elasticities can estimate reduced VT and
VMT that are assumed to be made on transit, even
if there is little or not transit service
25Recommendations Local Jurisdiction Practice
- Local jurisdictions with moderate-to-high-sensitiv
ity models should strive to continue to enhance
their models for Smart-Growth sensitivity - Local jurisdictions with low-sensitivity models
should consider using a 4D post processor
26Recommendations Research Development and
Training
- More research, development and training needed to
support more sophisticated modeling by local
jurisdictions - More research should be conducted to support 4D
elasticities or other post processing methods