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Emissions Analysis Techniques for TCMs

Forecasting Approaches

Selecting a Method

Descriptions of Available Methods

Key Inputs and Outputs for Each Method

List of Acronyms

Key Inputs and Outputs for Each Method

Improved Transit
HOV Lanes
Park and Ride
Carpooling and Vanpooling Promotion
Employer-Based TDM
Bicycle and Pedestrian Facilities
Traveler Information
Telecommuting/Work Hours
Pricing/Subsidies
Land Use
Parking Management
Traffic Flow Improvements
Incident Management
Freight/Intermodal
Idle Control
Alternative Fuel Vehicles

Strategy and Method	Key Inputs	Outputs
*Improved Transit*
TDM Evaluation Model	Change in travel time and/or cost by transit	Trips, VMT
TCM/Commuter Choice Model	Change in travel time and/or cost by transit	Trips, VMT, Emissions
TCM Analyst/EPA TCM Methodology	Percent change in fares or service frequency, or survey data on ridership (shuttle)	Trips, VMT, Emissions
CM/AQ Evaluation Model	Percent change in transit fare, wait time, travel time, and/or total revenue-miles; number of riders (shuttle)	Trips, VMT, Emissions
TCM Tools	Percent change in fare/cost of using transit	Trips, VMT, Emissions
Off-Net/PAQONE	Strategies: bus shelters, bike access, service changes, new service, transit center. Data: variously include daily boardings, adjacent pop., current local mode share, change in revenue miles, headways, route travel times, wait/access times	Trips, VMT, Emissions
ECO/Regulation XV Software	Change in travel time and/or cost by transit	Trips, VMT
California Standardized Methodology	New transit riders by prior mode of travel	Trips, VMT, Emissions
RAQC Workbook	Percent increase in service (peak-period departures)	VMT, Emissions
NCTCOG Sketch-Plan Methods	Rail: Average daily ridership, previous mode of rail travelers	Emissions
Quick-HOV	Traffic volumes and physical characteristics (length, lanes, etc.) of HOV/bus lane and parallel facility	Trips, Emissions
SMART	Change in travel time, cost by link in transit network	Trips, VMT, Emissions

Strategy and Method	Key Inputs	Outputs
*HOV Lanes*
TDM Evaluation Model	Changes in travel time by HOV lane	Trips, VMT
TCM Analyst/EPA TCM Methodology	Number of HOV lane-miles	Trips, VMT, Emissions
CM/AQ Evaluation Model	Increase in number of HOVs	Trips, VMT, Emissions
TCM Tools	Miles of HOV lanes added	Trips, VMT, Emissions
NCTCOG Sketch-Plan Methods	Before/after traffic volumes and speeds (freeway and parallel arterial); length of facilities	Emissions
Quick-HOV	Traffic volumes and physical characteristics (length, lanes, etc.) of HOV lane and parallel facility	Trips, Emissions
SMART	Addition of HOV link(s) to network, and time/cost characteristics	Trips, VMT, Emissions

Strategy and Method	Key Inputs	Outputs
*Park and Ride*
CM/AQ Evaluation Model	Number of spaces, utilization rate	Trips, VMT, Emissions
TCM Tools	Number of spaces, utilization rate	Trips, VMT, Emissions
Off-Net/PAQONE	Number of new spaces, utilization rate	Trips, VMT, Emissions
MWCOG Sketch-Plan Methods	Total number of spaces; work trip length	Trips, VMT, Emissions
NCTCOG Sketch-Plan Methods	Number of spaces, utilization rate, speeds on adjacent freeway	Emissions

Strategy and Method	Key Inputs	Outputs
*Carpooling and Vanpooling Promotion*
TDM Evaluation Model	"Level" of employer-based program in impact area	Trips, VMT
TCM/Commuter Choice Model	"Level" of employer-based program in impact area	Trips, VMT, Emissions
TCM Analyst/EPA TCM Methodology	Vanpooling: number of vanpools, average vehicle occupancy	Trips, VMT, Emissions
CM/AQ Evaluation Model	Number of new ridesharers	Trips, VMT, Emissions
CUTR_AVR	Whether guaranteed ride home or ridematching program are in place	Trips
TCM Tools	Percent increase in non-drive alone modes	Trips, VMT, Emissions
ECO/Regulation XV Software	Provision of guaranteed ride home, company vehicle, transportation coordinator, rideshare matching, vanpools, preferential parking	Trips, VMT
California Standardized Methodology	Number of commuters by new and prior mode of travel	Trips, VMT, Emissions
MWCOG Sketch-Plan Methods	Survey data on rideshare service utilization/placement	Trips, VMT, Emissions
NCTCOG Sketch-Plan Methods	Number of vanpools, minimum riders/vanpool	Emissions

Strategy and Method	Key Inputs	Outputs
*Employer-Based TDM*
TDM Evaluation Model	Assume other strategies to achieve trip reduction or AVR increase of X percent	Trips, VMT
TCM/Commuter Choice Model	Assume other strategies to achieve trip reduction or AVR increase of X percent	Trips, VMT, Emissions
CM/AQ Evaluation Model	Transit pass subsidy amount; number of people switching to each mode	Trips, VMT, Emissions
ECO/Regulation XV Software	Eligibility for various incentives; marketing and administrative expenditures	Trips, VMT
California Standardized Methodology	Number of commuters by new and prior mode of travel	Trips, VMT, Emissions
NCTCOG Sketch-Plan Methods	Number of companies with TDM programs, reported number of active participants	Emissions

Strategy and Method	Key Inputs	Outputs
*Bicycle and Pedestrian Facilities*
TCM/Commuter Choice Model	"Level" of bicycle/pedestrian support program	Trips, VMT, Emissions
TCM Analyst/EPA TCM Methodology	Vehicle volumes on roads adjacent to proposed trails; percent switching mode	Trips, VMT, Emissions
CM/AQ Evaluation Model	Number of new walkers/bicyclists or percent of trips that would bicycle	Trips, VMT, Emissions
TCM Tools	Percent of trips that would bicycle	Trips, VMT, Emissions
Off-Net/PAQONE	Size of service area, population density, existing mode share, length of existing and new bike network; budget for promo. programs; bike coordinator	Trips, VMT, Emissions
ECO/Regulation XV Software	Provision of bicycle racks or storage, provision of showers and lockers	Trips, VMT
California Standardized Methodology	Number of commuters by new and prior mode of travel	Trips, VMT, Emissions
RAQC Workbook	Population served by bike facilities	VMT, Emissions
MWCOG Sketch-Plan Methods	Utilization and trip lengths for various strategies	Trips, VMT, Emissions
NCTCOG Sketch-Plan Methods	Size of service area, population density, bicycle mode share, length of project	Emissions

Strategy and Method	Key Inputs	Outputs
*Traveler Information*
CM/AQ Evaluation Model	ATIS: percent increase in transit ridership; motorist info: trip reduction during incidents	Trips, VMT, Emissions
Off-Net/PAQONE	Freeway section length, baseline speed and volume	Trips, VMT, Emissions
IDAS	Types and locations of deployed ITS strategies	Trips, VMT, Emissions

Strategy and Method	Key Inputs	Outputs
*Telecommuting/Work Hours*
TDM Evaluation Model	Eligibility and participation in flex-time, staggered hours, telecommute, 4/40 or 9/80 work week	Trips, VMT
TCM/Commuter Choice	Model Eligibility and participation in flex-time, staggered hours, telecommute, 4/40 or 9/80 work week	Trips, VMT, Emissions
TCM Analyst/EPA TCM Methodology	Percent of eligible people telecommuting (home or satellite); avg. days/week	Trips, VMT, Emissions
CM/AQ Evaluation Model	Telecommuting, compressed hours: participation rate and days/week, shift from peak to off-peak	Trips, VMT, Emissions
CUTR_AVR	Whether a compressed work week is in place	Trips
TCM Tools	Telecommuting, compressed hours: participation rate and days/week, shift from peak to off-peak	Trips, VMT, Emissions
ECO/Regulation XV Software	Eligibility and participation in flex-time, staggered hours, telecommute, 4/40 or 9/80 work week	Trips, VMT
California Standardized Methodology	Number of commuters by new and prior mode of travel	Trips, VMT, Emissions
RAQC Workbook	Telecommuting, compressed hours: participation rate and days/week	VMT, Emissions
MWCOG Sketch-Plan Methods	HBW trip lengths and utilization of telecommute centers in outlying areas	Trips, VMT, Emissions

Strategy and Method	Key Inputs	Outputs
*Pricing/Subsidies*
TDM Evaluation Model	Changes in travel cost by mode to impact area	Trips, VMT
TCM/Commuter Choice Model	Changes in travel cost by mode to impact area	Trips, VMT, Emissions
TCM Analyst/EPA TCM Methodology	Percent change in travel cost by mode	Trips, VMT, Emissions
CM/AQ Evaluation Model	Increase in cost per gallon or cost per mile; percent change in transit cost; parking charge	Trips, VMT, Emissions
CUTR_AVR	Whether higher costs for driving alone or alternative mode use subsidies are in place	Trips, AVR
TCM Tools	Increase in cost per gallon or cost per mile; percent change in transit cost; parking charge	Trips, VMT, Emissions
ECO/Regulation XV Software	Changes in travel cost by mode to impact area; change in parking cost	Trips, VMT
California Standardized Methodology	Number of commuters by new and prior mode of travel	Trips, VMT, Emissions
RAQC Workbook	Increase in cost per gallon, VMT, or trip; peak-period tolls; parking charge; parking cash-out; pay-at-the-pump insurance	VMT, Emissions
MWCOG Sketch-Plan Methods	Free midday fares: percent increased ridership by mode shift, time shift, other	Trips, VMT, Emissions
SMART	Change in cost of travel by link, zone	Trips, VMT, Emissions

Strategy and Method	Key Inputs	Outputs
*Land Use*
CM/AQ Evaluation Model	Percent increase in density, mixed use, pedestrian amenities in employment centers	Trips, VMT, Emissions
TCM Tools	Percent increase in density, mixed use, pedestrian amenities in employment centers	Trips, VMT, Emissions
RAQC Workbook	Site design: grid streets, density standards, etc.; regional growth management; infill development	VMT, Emissions
MWCOG Sketch-Plan Methods	Allow convenience uses in residential areas (trip generation, mode share, trip lengths)	Trips, VMT, Emissions
SMART	Change in location of development by zone	Trips, VMT, Emissions

Strategy and Method	Key Inputs	Outputs
*Parking Management*
TCM Analyst/EPA TCM Methodology	Percent change in parking cost	Trips, VMT, Emissions
CM/AQ Evaluation Model	Change in vehicle-trips to site and elsewhere, number of short-term and long-term spaces	Trips, VMT, Emissions
RAQC Workbook	Current parking space utilization, cap on parking spaces, maximum parking ratios	VMT, Emissions
MWCOG Sketch-Plan Methods	Maximum parking ratios, employment, trips, mode share by area	Trips, VMT, Emissions

Strategy and Method	Key Inputs	Outputs
*Traffic Flow Improvements*
TCM Analyst/EPA TCM Methodology	Percent change in traffic speed; affected VMT	Emissions
CM/AQ Evaluation Model	Percent change in traffic speed; affected VMT	Emissions
TCM Tools	Percent change in traffic speed; reduction in trips	Emissions
Off-Net/PAQONE	Arterial improvements: baseline speeds, volumes, LOS; improvements made and added capacity	Emissions
MWCOG Sketch-Plan Methods	Flashing yellow: number of signals, traffic counts, savings/signal; ATMS: speed increase, emission rates by speed	Emissions
NCTCOG Sketch-Plan Methods	Project-specific average speed improvements, traffic volumes, distance affected	Emissions
IDAS	Types and locations of deployed ITS strategies	Trips, VMT, Emissions
SMART	Change in capacity, travel speeds of links in transportation network	Trips, VMT, Emissions
Traffic Simulation Models	Roadway and intersection characteristics, traffic and turning volumes	Emissions

Strategy and Method	Key Inputs	Outputs
*Incident Management*
Off-Net/PAQONE	Freeway section length, baseline speed and volume	Emissions
NCTCOG Sketch-Plan Methods	Traffic volumes affected; change in speeds and incident duration as a result of strategies	Emissions
IDAS	Types and locations of deployed ITS strategies	Emissions

Strategy and Method	Key Inputs	Outputs
*Freight/Intermodal*
CM/AQ Evaluation Model	Number of trucks shifted from peak to off-peak	Emissions
TCM Tools	Number of trucks shifted from peak to off-peak	Emissions
Freight Air Quality Analysis Procedures	Various methodologies and inputs for determining freight activity levels and emission factors	Emissions

Strategy and Method	Key Inputs	Outputs
*Idle Control*
CM/AQ Evaluation Model	Number of sites impacted, number of affected trips/ vehicles, idling time/vehicle	Emissions
MWCOG Sketch-Plan Methods	Vehicles affected, idle time, idle emission factors (from MOBILE)	Emissions

Strategy and Method	Key Inputs	Outputs
*Alternative Fuel Vehicles*
CM/AQ Evaluation Model	Number of affected trips, emission rates	Emissions
NCTCOG Sketch-Plan Methods	Number of vehicles by agency and fuel type; relative emission rates	Emissions
AirCred	Number of alternative fuel vehicles purchased by vehicle type and fuel type, miles driven per year	Emissions
Bus Replacement Spreadsheet	Number of buses procured and retired by model year and fuel type	Emissions

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