First home-interview survey (1944)
Gravity model
1
Where do the trips
produced in TAZ 3 go?
?
2
?
3
?
4
?
5
Gravity model equation
Attractiveness of “from” taz
Forecasted flows between
= Trips attracted to TAZ i
zone i and zone j
Attraction constrained
tripsij  attractions j 
Attractiveness of all tazes
productionsi  FFij  K ij
 productions
k
 FFik  K ik
where,
Relative attractiveness
Tripsij: trips between TAZs i and j,
Productionsi: the productions from TAZ i,
Attractionsj: the attractions to TAZ j,
Friction factor (FFij): friction factor for TAZs i and j,
Socioeconomic factor (Kij): socioeconomic adjustment factor for TAZs i and j,
i: production TAZ
i: attraction TAZ
An example tree
Conventional urban travel forecasting
process
• Includes four technical phases
– Collection of data
– Analysis of data
– Forecasts of activity and travel
– Evaluation of alternatives
Travel demand forecasting
– the four step model
Estimating the kinds of
trips generated
Trip generation
Trip distribution
Mode split
Trip assignment
Deciding the routes taken by the trips
Distributing the generated
trips in space
deciding how trips
are made in terms
of modes
MPO: Metropolitan Planning
Organization
A transportation policy-making organization
made of representatives from local
government and transportation authorities
Five core functions of MPO
•
•
•
•
•
Establish a setting
Evaluate alternatives
Maintain a long-range plan
Develop a short-range plan
Involve the public
Products produced by MPOs
Time/horizon
Contents
Update
requirements
UPWP
1-2 years
Planning studies
and tasks
Annually
PLAN
25 years
Future goals,
strategies and
projects
Every 5 years
TIP
3 years
Transportation
improvements
Every 2 years
Key decisions in long-range planning
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
Approve scope of LRTP process
Approve vision and goals
Approve evaluation criteria, methods and measures
Approve transportation deficiencies
Approve financial assumptions
Approve strategies
Approve plan scenarios
Adopt preferred plan scenario
Adopt finding of conformity by MPO
Adopt LRTP by MPO
Approve conformity analysis
Conformity
• Transportation investments must conform to
the state implementation plan (SIP) for
meeting air quality standards.
• Conformity is a way to ensure that Federal
funding and approval are given to those
transportation activities that are consistent
with air quality goals.
Transportation Conformity Process
Yes
SIP
No
or
Plan
Revision
needed
TIP
Emission
budget
Yes
TCMs
STP
Revision
needed
Perform regional analysis for plan
•Compare build vs. no-build
State
Conformity
procedure
•Emission budget
•Timely implementation of TCMs
Transportation plan
No
TIP conformity
No
Yes
Perform regional analysis for plan
No
Project
TIP
Revision
needed
•Compare build vs. no build
Hot Spot analysis
•Emission budget
•Timely implementation of TCMs
No
Yes
Plan conformity
No
Project summary
Project approval
What are subject to conformity?
• Transportation plans
• Transportation improvement programs
Who makes conformity determination?
What is the frequency of conformity
determination?
Options to reduce emissions from
vehicles
•
•
•
•
•
Vehicle controls
Fuel-based standards
Inspection and maintenance programs
Transportation control measures
Market-based Transportation Control
Measures
A multi-modal program includes:
• Land use management (examples only)
–
–
–
–
–
Planning and zoning
Phasing and adequacy
Urban design
Mixed use
Density
• Demand management (examples only)
–
–
–
–
–
Alternative work schedule
Pricing
Alternative modes
Alternative work locations
Employer support programs
A multi-modal program includes:
• Supply management
– Intelligent transportation system
– Transit facilities and services
– Intermodal facilities
– Traffic engineering
– Highway capacity and bike/walkways
What is this urban transportation planning
process really?
A realistic perspective
NIMBY: not in my back yard
Other acronyms
• LULU: locally unwanted land use
• NIMTOO: not in my term of office
• BANANA: build absolutely nothing anywhere
near anyone
• NOPE: not on planet earth
• CAVES: citizens against virtually anything