Summit in the Wasatch John Britting Wasatch Front Regional Council

Context – Fall 2001 First light rail line was very successful First light rail line was very successful Local transit priority was commuter rail Local transit priority was commuter rail Transit dedicated sales tax increase was passed Transit dedicated sales tax increase was passed Bold promises made re: CRT Bold promises made re: CRT Initial forecasts from corridor study were high (~35,000) and made FTA very uncomfortable Initial forecasts from corridor study were high (~35,000) and made FTA very uncomfortable Lawsuits over analytical methods Lawsuits over analytical methods My boss was handing over the reigns to me My boss was handing over the reigns to me

Step 1: Engage FTA Hired PB Consult to upgrade models Hired PB Consult to upgrade models Brought in FHWA/FTA for a focused peer review of models in January, 2002 Brought in FHWA/FTA for a focused peer review of models in January, 2002 Opened up the black box and welcomed feedback Opened up the black box and welcomed feedback Short-term and longer term priorities for model improvements were developed Short-term and longer term priorities for model improvements were developed Synopsis: make every step better in short-term Synopsis: make every step better in short-term

Priorities – FTA Perspective Estimate/calibrate & validate NL mode choice models using local data Estimate/calibrate & validate NL mode choice models using local data Pay close attention to path-building Pay close attention to path-building Identify CW/MD/NT markets Identify CW/MD/NT markets Incorporate segmentation into distribution Incorporate segmentation into distribution Consider handling unique markets differently (e.g. college trips and airport trips) Consider handling unique markets differently (e.g. college trips and airport trips) Thorough validation of network speeds Thorough validation of network speeds

Step 2: Progress as of 6/03 Borrow NL mode choice models and calibrate using local data (collected on-board data) Borrow NL mode choice models and calibrate using local data (collected on-board data) Little improvement to path-building Little improvement to path-building Identified CW/MD/NT markets Identified CW/MD/NT markets Did not incorporate segmentation into distribution Did not incorporate segmentation into distribution Used data on student addresses and an airport users survey to developed unique trip tables Used data on student addresses and an airport users survey to developed unique trip tables Thorough validation of network speeds Thorough validation of network speeds

Step 3: Continue Dialog Questions remained about forecasts Questions remained about forecasts High non-work benefits High non-work benefits Significant reverse commute Significant reverse commute Questions remained about validation Questions remained about validation Summarized rail trips by # transfers and attraction district for each trip purpose and auto segment (example next slide) Summarized rail trips by # transfers and attraction district for each trip purpose and auto segment (example next slide) Agreed on a range for forecasts and helped them tell the story with some confidence Agreed on a range for forecasts and helped them tell the story with some confidence CRT was given a “recommended” CRT was given a “recommended”

Step 4: Identify Illogical Benefits

Step 5: Progress as of 6/04 Estimated/calibrated & validated NL mode choice models using local data Estimated/calibrated & validated NL mode choice models using local data Transit path-building informed by on-board and model estimation (consistent weights; 95% of on-board records had access; reasonable xfer rates) Transit path-building informed by on-board and model estimation (consistent weights; 95% of on-board records had access; reasonable xfer rates) Identified CW/MD/NT markets Identified CW/MD/NT markets 0-car HBW distribution w/composite impedance 0-car HBW distribution w/composite impedance Used data on student addresses and an airport users survey to developed unique trip tables Used data on student addresses and an airport users survey to developed unique trip tables Thorough validation of auto speeds; model relating transit speeds to auto speeds Thorough validation of auto speeds; model relating transit speeds to auto speeds

Most Important Step - Validate Trips by purpose, market, period and mode Trips by purpose, market, period and mode Boardings by route and route group Boardings by route and route group District-level trip tables District-level trip tables Results from on-board assignment Results from on-board assignment % person trips with a transit path, by market % person trips with a transit path, by market % transit trips for each market by mode and transfers % transit trips for each market by mode and transfers % walk-rail that are walk-bus-rail % walk-rail that are walk-bus-rail Expressed constants/parameters in terms of IVT Expressed constants/parameters in terms of IVT

Threat 1 – naïve calibration/validation Extensive documentation Extensive documentation Asked FTA what they wanted to see Asked FTA what they wanted to see Built a calibration routine into models (in TP+) and several scripts to automate reporting of key indicators Built a calibration routine into models (in TP+) and several scripts to automate reporting of key indicators

Threat 2 – Incorrect Travel Markets Estimated, calibrated and validated a best- practice auto ownership model Estimated, calibrated and validated a best- practice auto ownership model 0-car HBW distribution 0-car HBW distribution College and Airport trip tables College and Airport trip tables

Threat 3 – Odd Properties FTA reviewed and commented on model estimation results, model functional form and implementation FTA reviewed and commented on model estimation results, model functional form and implementation Expressed all parameters and coefficients in terms of equivalent in-vehicle minutes Expressed all parameters and coefficients in terms of equivalent in-vehicle minutes

Threat 4 – Transit Path Builder Overhaul of walk/drive support link generation models Overhaul of walk/drive support link generation models Used initial estimation results to refine path- building weights Used initial estimation results to refine path- building weights Built MC estimation file 2-3 times Built MC estimation file 2-3 times Assigned transit on-board Assigned transit on-board Quality of O-D data Quality of O-D data Assure access where trips occurred Assure access where trips occurred Refine path-building parameters Refine path-building parameters

Threat 5 – Inaccurate Speeds Performed extensive auto speed data collection Performed extensive auto speed data collection Used data to calibrate and validate auto assignment Used data to calibrate and validate auto assignment Built model to forecast transit speeds from auto speeds; based on facility type and auto speed – model does a very good job Built model to forecast transit speeds from auto speeds; based on facility type and auto speed – model does a very good job

How we’ve used Summit Network quality control – does the distribution of benefits seem reasonable? Network quality control – does the distribution of benefits seem reasonable? Tell the story of who benefits Tell the story of who benefits LRP - benefits per capita analysis LRP - benefits per capita analysis Identify symptoms of quirks in the models Identify symptoms of quirks in the models

Concerns with Summit Process A lot of work for me A lot of work for me Not sure FTA has staff to go through similar process across the country Not sure FTA has staff to go through similar process across the country How do you get a baseline approved? How do you get a baseline approved? The cap has to be flexible The cap has to be flexible Old-school program Old-school program Summit proves models are not perfect, which we all should already understand Summit proves models are not perfect, which we all should already understand

Case for Higher Cap Differences in transit utility may reasonably exceed the cap of 45 minutes Differences in transit utility may reasonably exceed the cap of 45 minutes Travel time differences (IVT and OVT) Travel time differences (IVT and OVT) Transfer differences Transfer differences Unobserved attributes (i.e. constants) Unobserved attributes (i.e. constants) This assumes you minimize or eliminate This assumes you minimize or eliminate Coverage differences Coverage differences Service level differences Service level differences Access differences Access differences

Recommendations FTA should ask for specific items to be documented FTA should ask for specific items to be documented Process to justify cap increases Process to justify cap increases Process for defining range of key indicators Process for defining range of key indicators Modelers, not PM’s, need to open up to FTA early and often Modelers, not PM’s, need to open up to FTA early and often Work with Citilabs, Caliper, etc., to improve Summit Work with Citilabs, Caliper, etc., to improve Summit Recognize inherent imperfections and overcome most critical Recognize inherent imperfections and overcome most critical Start process early Start process early

Final Comment Our commuter rail forecast went down from 35,000 boardings to 26,000 and our forecast is much better.