SAN FRANCISCO COUNTY TRANSPORTATION AUTHORITY Making Activity-Based Travel Demand Models Play Nice With Trip Rates Elizabeth Sall, Daniel Wu, Billy Charlton

SAN FRANCISCO COUNTY TRANSPORTATION AUTHORITY

Making Activity-Based Travel Demand Models Play Nice With

Trip Rates

Elizabeth Sall, Daniel Wu, Billy Charlton

TRB Planning Applications Conference – Reno, NVMay 2011


2

Objective

Develop a lookup table for auto vehicle trip ends by

land use square footage that accounts for accessibility.


3

Possibilities ?

SF ObservedDataSF-CHAMP

pow

pow

pow

pow

pow

poof!

Validated

Uniqueness of SF

“The Ds” and transit systemCurrently on the ground

Future changes to “the Ds” and transit system

Easy to get trip rates by specific Land Use Category

meh


4

Are they a worker? Are they a student?How many jobs? Are they part time?What is their income? How old are they?Do they have a car? Do they have a license?Do they have kids? Are they a woman?How many workers are in the household?How many cars per worker?What is their accessibility to all destinations from

home considering the cars per worker in their household?

What is their accessibility to work or school considering the cars per worker in their household?

Trip Rates!?!?…but there’s so much that goes into determining if a trip is made!!!


5

Can’t distinguish which job actually pulled that trip into the TAZ – all part of a size term.

Different size terms for: Trip purpose Primary destinations versus

intermediate stops

By Land Use Category!?!?


6

Multiple linear regression on model results: Vehicle Trip Ends for zone z =

B * Households +B * Cultural/Institutional Employees + B * Medical Employees +B * Office Employees +B * PDR Employees +B * Visitor/Hotel Employees +B * Retail Employees

Segment regressions based on simple accessibility groupings.

Reverse-Engineering the AB Model to ‘make it simple’


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Accessibility Variables

Requirements:Encourage development consistent with

San Francisco’s “transit first” policySimple to calculate or look up on a mapAccount for wide variations in vehicle

trip rates across the city


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Accessibility Variables Considered

Transit Intensity (combined headways)Employment DensityHousehold Density


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“Accessibility Zone” Map


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Final Auto Vehicle Trip Rates

BASE/LOW MEDIUM HIGH

HHLDS 7.5 -3.0 -3.5

CIE 7.3

-3.0MED 4.7

RET 10.5

VIS 7.9

PDR 6.0

MIPS 1.9

Accessibility Adjustments


Questions?

[email protected]

Special Thanks: Viktoriya Wise, Stephen Newhouse, Dan Wu & Rachel

Hiatt


AUTO TRIP MITIGATION FEE // MAPS & CORR

ZONE 1: Within ½ mi of Rapid Transit*ZONE 2: Within ½ mi of Other Transit**ZONE 3: All Else

ZONE 1: Within ¼ mi of Rapid TransitZONE 2: Within ¼ mi of Other TransitZONE 3: All Else

ZONE 1: Within ½ mi of Rapid TransitZONE 2: Within ¼ mi of Other TransitZONE 3: All Else

A

B

C

* Rapid Transit includes BART and the “Rapid Network” as defined by MUNI (All rail plus major bus routes)

** Other Transit includes any other transit stop

Scenarios


AUTO TRIP MITIGATION FEE // MAPS & CORR

ZONE 1: Within ½ mi of Rail (BART or MUNI)ZONE 2: Within ½ mi of Other TransitZONE 3: All Else

ZONE 1: Within ¼ mi of RailZONE 2: Within ¼ mi of Other TransitZONE 3: All Else

ZONE 1: Within ½ mi of RailZONE 2: Within ¼ mi of Other TransitZONE 3: All Else

E

F

G

Scenarios


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Transit Intensity Calculation


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Thresholds Used

HIGH LOW

TRANSIT

Combined Headway of all routes with stops within ¼ mi <=1 min

Combined Headway of all routes with stops within ¼ mi >1 min

EMPLOYMENT

>= 50 jobs/acre

< 50 jobs/acre



< = 1 min

> 1 min

TRANSIT INTENSITY

(Detail)


EMPLOYMENT DENSITY

(Detail)


HOUSEHOLD DENSITY

(Detail)


ZONE MAP

Combines transit intensity, employment density, and household density into eight zones.


ZONE MAP(Detail)

Documents

SAN FRANCISCO COUNTY TRANSPORTATION AUTHORITY Making Activity-Based Travel Demand Models Play Nice With Trip Rates Elizabeth Sall, Daniel Wu, Billy Charlton