quick reference guide for traffic planner/engineers for
TRANSCRIPT
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presented to presented by
Quick Reference Guide for Traffic Planner/Engineers for Generating Traffic and Activity Data for Project-Level AQ Analyses
NCHRP 25-25B Task 96
AASHTO Air Quality, Climate Change, and Environment Subcommittee
Helen Ginzburg, VHB, Inc.
Chris Porter, Cambridge Systematics, Inc.
March 6, 2020
Acknowledgments
Principal Investigator:» Helen Ginzburg (WSP, now VHB)
Key Staff:» Victor Teglasi (WSP)
» Pascal Volet (WSP, now Aimsun)
» Chris Porter (CS)
» David Kall (CS, now FHWA)
NCHRP Senior Program Officers:» Lori Sundstrom and Ann Hartell
Project Panel:» Christopher Voigt, Virginia DOT
(Chair)
» Charles Baber, Baltimore Metropolitan Council
» Brian Dunn, Oregon DOT
» Alan Horowitz, AJH Associates
» Subrat Mahapatra, Maryland SHA
» Marilee Mortenson, California DOT
» Timothy Sexton, Minnesota DOT
» Gabriel Contreras & Timothy Wood, Texas DOT
» Paul Heishman, FHWA Resource Center
Purpose
Assist traffic analysts who work with traffic data and models in providing the traffic data required for emissions modeling and air quality analysis for transportation projects
» Bridge the gap between the fields of traffic and air quality analyses
» Support early coordination to reduce delays
Supplement to NCHRP Report 765, Analytical Travel Forecasting Approaches for Project-Level Planning and Design
The Traffic – Air Quality Data Link
• Field Data Collection
• Project-Level Traffic Modeling
Traffic Activity Data
• Vehicle Emissions Models
• MOVES (EMFAC)
Emissions Quantities
• Air Quality Dispersion Models
• AERMOD
• CAL3QHC/R1
Pollutant Concentrations
• Calculate Design Values and Conduct Tests (NAAQS and BD/NB)
• Prepare Documentation
Summarize Results
Air Quality
Practitioners
Coordinate Early On:
Identification of potential traffic and air quality impacts
Availability of traffic data and forecasts
Study area/links included
Timeline for project development
Traffic data needs and requests
Plans for more refined traffic analysis
Sensitive locations/ receptors in project vicinity
Pollutants
Alternatives
Analysis years and time periods
Key assumptions
Guide Organized by Pollutant
Conformity NEPA
State
Environmental
Policies
Ch. 3 - Carbon monoxide (CO)
Ch. 4 - Particulate matter (PM)
Ch. 5 - Mobile source air toxics (MSAT)
Ch. 6 - Greenhouse gas (GHG)
Ch. 2 – Overview of Traffic Data Needs in AQ Analysis
Ch. 7 – Special Topics
Ch. 8 – References
Appendices
Ch. 2 – Traffic Data Needs Topics
Typical steps:
1. Preliminary assessment
2. Screening data/forecasts
3. Detailed data/forecasts
4. Mitigation
Traffic volumes
» Base year & forecasts
» Classification
» Temporal detail (hours)
» Generated & diverted traffic
» Background growth
Traffic speeds
» Existing and forecast
Other data
» Signal timing
» Start, parked, hoteling fractions
Data Sources and Methods Table
Project
Stage/Step
Traffic/ Activity
Input
Impact on
Emissions and
Concentrations Method Bas
e Y
ear
Fu
ture
Yea
r
References Comments
Project
Assessment,
Step 1
Intersection LOS
at locations
potentially
affected by the
project
Important if future
year LOS is D or
worse
LOS is usually an output of traffic
analysis or traffic simulation
software
X X NCHRP Report
765, 2.3.1, 2.4.3
If LOS is not included in the
general model output, NCHRP
Report 765 describes in detail
the HCM Sixth Edition
computational methodology
X X NCHRP Report
765, Section 10.4,
pp 252-257
Etc.
Ch. 7 – Special Situations
Advanced traffic modeling methods when using MOVES operating mode distribution or drive schedule inputs
Reevaluations under NEPA
Traffic mitigation measures as they are affected by the air quality modeling results
Litigation risk management
Ch. 8 - References
Traffic Data Sources
General Emissions and Air Quality Modeling Guidance
Guidance by Pollutant
Some State and Local Regulations and Guidance
Traffic Mitigation
Litigation Risk Management and Reevaluations
Appendices
A - Sample two-page “traffic information request forms” that list the key traffic data items required for CO, PM, and MSAT
B - Examples of traffic information provided for air quality analyses
C - Definitions for air quality modeling
D - Definition of “links” in air quality modeling vs. traffic analysis
Further Information & Contacts
Guide published at:
» http://onlinepubs.trb.org/onlinepubs/nchrp/docs/NCHRP25-
25(96)_QRG.pdf
Ann Hartell, Senior Program Officer, [email protected]
Helen Ginzburg, VHB, [email protected]
Chris Porter, Cambridge Systematics, [email protected]