SAFETEA-LU Evaluation and Assessment Phase I

• Miles of urban minor arterial affected: 15 miles
• Daily, 2-way traffic volume = 23,519 vehicles with 40% of travel occurring in peak periods.
  • Peak VMT = 15 miles * 23,519 vehicles * 0.4 = 141,114 miles
  • Off Peak VMT = 15 miles * 23,519 vehicles * 0.6 = 211,671 miles
• Travel Speeds before project are 31 mph in peak, and 41 mph in off-peak.
• Travel Speeds after project are 35 mph in peak, and 45 mph in off-peak.

• Emissions reductions calculated using Mobile 5a running emissions factors (g/mile) for VOC at the following speeds:
  • Peak:31 mph: VOC = 1.84335 mph: VOC = 1.697
  • Off Peak:41 mph: VOC = 1.52645 mph: VOC = 1.434
• Calculate daily emissions reduced = (change in peak emissions * Peak VMT) + (change in off-peak emissions * Off-peak VMT)
  • VOC Emissions = ((1.697 - 1.843) * 141,114 miles) + ((1.434 - 1.526) * 211,671 miles) / 1,000 = - 40.076 kg/day

Travel analysis performed by VISSIM Microscopic Simulation model used recent traffic counts and traffic signal information to give an average delay in seconds per vehicle at the intersection. (Total Delay = Peak Hour volume * Average Delay in sec/veh/3600). Hourly reduction in delay is calculated separately for the AM and PM peak periods and summed.

The analysis showed that the proposed improvements would enhance traffic flow during peak hours increasing from 5,800 to 6,500 VPH in the AM peak, and from 6,200 to 6,700 VPH in the PM peak. Average delay would drop from 92.6 to 36.0 sec/veh in the AM peak, and 178.3 to 34.4 sec/veh in the PM peak. Net reduction in delay is 84.2 veh-hr/hr in the AM peak and 304.5 veh-hr/hr in the PM peak.

Intersection analysis also shows change in LOS for each intersection segment.

• Emissions reductions calculated from changes in delay.
• Emissions factors were developed using MOBILE6, using 2.5 Mph speed, and converted into idle emissions factors.
• Emissions factor for VOC = 10.35 g/mi
• Emissions factor for NOX= 2.67 g/mi

Emissions reduction = Delay in vehicle-hours/hour * Emissions Factor * 2.5 (conversion of gm/mi to gm/hr) * 2 hours per day (calculated for 2-hour Am peak and 2-hour Pm peak separately, and summed)

Delay = 4 minutes per vehicle, based on a report on the Integrated Traffic SigNAl System from 2001, which determined the reduction in delay and corresponding emissions savings by using an average reduction for 18 intersections and projecting it throughout the total system.

Vehicle counts provided by Kentucky Transportation Cabinet, Division of Planning

Emissions factors are based on EPA calculations for general vehicle fleet mix. The percentage of vehicle types or classifications was used to determine the grams of pollutant reduced per minute by the reduction in delay, using Our Nation's Highways, from the Federal Highway Administration (FHWA).

(average of vehicle counts per arterial) x (minute of delay reduced by fiber optic) x (g/min per VOC, NOx, CO) = total grams VOC, NOx, CO per day

Modeling done using Syncro Version 5 for the PM period. There is minor congestion during the entire business day, so the AM and PM Peak Periods are similar. The change in delay was calculated for four (4) intersections using the following formula: (Approach Volume * Stop Control Delay) (Approach Volume * Signalized Delay) = Total Delay Reduction

• SR79S (1,568 veh * 26.1 veh/sec) (1,568 veh * 6.5 veh/sec) = -8.54 hours/day
• SR79N (1,523 veh * 1,579 veh/sec) (1,523 veh * 15.5 veh/sec) = -661.7 hour/day
• Union St. (1,580 veh * 9.2 veh/sec) (1,580 veh * 22.6 veh/sec) = +5.88 hours/day
• 11th St. (1,536 veh * 95.4 veh/sec) (1,568 veh * 7.2 veh/sec) = -37.63 hour/day

Emissions reductions calculated using Mobile6. Idle emissions calculated using exhaust emissions for a 2.5 mile/hour average speed.

The Mobile Factors used Main Street as a Minor Arterial Urban Class 16 and all intersecting streets as Local Urban Class 19 to determine emissions.

• Daily VMT = 25,935 average daily traffic x 9.47 mile corridor length = 245,065 VMT on corridor.
• An average improvement in speed/travel of 12% for traffic signal upgrades of this type is noted in the publication "A Toolbox for Alleviating Traffic Congestion and Enhancing Mobility" from ITE.
• Average speed increased from 34 mph to 38 mph.

Emissions factors for before project implementation and after project implementation based on MOBILE6 and average speeds of 34 mph and 38 mph, respectively.

Emissions reduction = VMT x (Emissions Factor before project Emissions Factor after project)

• VOC Emissions reduction = 245,065 VMT x (1.883 1.826) / 1000 = 14.969 kg/day
• NOx Emissions reduction = 245,065 x (1.847 1.856) / 1000 = -2.206 kg/day

• Delay (vehicle-hours):
  • 2006 No-build = 362 vehicle-hours of delay
  • 2006 Build = 299 vehicle-hours of delay
• Change in delay due to project implementation = 362 - 299 = 63 vehicle-hours = 17% reduction in delay

Reduction in delay determined by the Synchro model output, based on a one-hour simulation. These one hour peak delay reductions, per day, were used to determine an average delay for two hours of peak travel reductions.

The delay reductions were used to calculate the emissions savings using emissions factors provided by US EPA Office of Transportation and Air Quality.

Reduction in delay * average of vehicle mix for kg/min per CO, NOx, VOC * 255 days per year.

48,670 average traffic volumes for Year 2009 were calculated using the CDTC STEP Model. The CDTC STEP Model forecast was validated using a 1999 intersection count and used to calculate seconds of delay for approach vehicles with the existing signalized intersection. The RODEL Roundabout Capacity Model was used to conduct an analysis of the Washington Avenue/Fuller Road intersection and was used to calculate seconds of delay for approach vehicles under the new, roundabout build scenario. (11.5 sec avg "No Build" delay 5 sec avg "New Roundabout" delay = 6.5 sec avg change in delay.

VMT was estimated using a quarter mile approach for each leg of the intersection. Speeds were calculated over that same distance as 15 mph under existing conditions and 29 mph with the roundabout.

The STEP model was also used to calculate seconds of delay for vehicles with the existing signalized intersection for the no-build scenario. The NYSDOT Roundabout Design Unit conducted an analysis of the proposed improvement using the RODEL Roundabout Capacity model to calculate seconds of delay for approach vehicles under the build scenario.

The NYSDOT software package CMAQtraq was used to estimate emissions, using the "Traffic Flow Improvements" module. Effects were calculated for 250 days/year with the following emissions factors (g/mile):

• CO = Before: 18.01 After: 16.02
• VOC = Before: 1.01 After: 0.71
• NOx = Before: 0.95 After: 0.79

The overall level of VMT and vehicle trips is not assumed to be affected. Emissions reductions will occur through a reduction in nonrecurring congestion.

Emissions factors for baton rouge based on MOBILE Model; assumed running speed of 40 MPH. Emissions reductions were applied to the length of I-10, as follows:

1. Freeway emissions = freeway VMT (from Tranplan model) * Emissions factor (from MOBILE in grams/mile)
2. Freeway emissions due to nonrecurring congestion = freeway emissions * 0.049 (assumes 4.9% of freeway emissions are caused by nonrecurring congestion using data from Lindley, J. A. "Urban Freeway Congestion: Quantification of the Problem and Effectiveness of Potential Solutions." 1987).
3. Emissions reduced due to program = freeway emissions due to nonrecurring congestion * effectiveness factor. Effectiveness factor assumed to be 0.90, based on effectiveness rate of 50% for Incident Detection and Response, 25% for Motorist Assistance, and 15% for Surveillance.

The assumptions for input into TCM Tools included the expectation that the project will improve both peak and off-peak period speeds by 10% (from 19 to 21 mph), with an average daily traffic (ADT) of 200,000 in 2010.

Emissions reductions calculated using the TCM Tools program created by Parsons Brinkerhoff and Sierra Research in 1994, which applies project data to the project year's (2004) MOBILE emissions factors and regional data to produce the emissions reductions for CO, VOCs, and NOx.

Length is 13.94 miles, 10.22 in Fairfield County and 3.72 miles in Greater Connecticut.

The "Connecticut Freeway Management System" report documents the effects of incident management systems. Based on the report, this type of system will result in annual delay savings of 1.72 million vehicle hours (MVH) for a corridor length of 65 miles, based on a congested incident speed of 5 mph, and a free flow speed of 55 mph. The daily VMT traveled without an IM system in place is 1.72 MVH x 5 mph / 365 days = 23,561 VMT.

For Fairfield County:

• VOC reduction = (1.700 0.490) x 23,561 / 65 miles x 10.22 miles = 4.48 kg/day
• NOx reduction = (1.988 1.395) x 23,561 / 65 miles x 10.22 miles = 2.20 kg/day
• PM_2.5 reduction = (0.288 0.287) x 23,561 / 65 miles x 10.22 = 0.004 kg/day

For Greater Connecticut Area:

• VOC reduction = (1.700 0.490) x 23,561 / 65 miles x 3.72 miles = 1.63 kg/day
• NOx reduction = (1.988 1.395) x 23,561 / 65 miles x 3.72 miles = 0.80 kg/day

• 306 total vehicles were relocated to ramps and 69 accidents were relocated from a travel lane. Data provided by Alabama DOT for 7/3/2006-6/29/2007 period.
• Estimated percentage of disabled vehicles which occur during peak period = 25%
• Estimated percentage of incidents which occur in peak period = 50%
• Total numbers of accidents (travel lane opened during project) = 111 accidents
• Traffic volume prior to project = 1400 vehicle/hour/lane
• Average number of blocked lanes during incidents = 1.1 lanes
• Average number of lanes for the InterState highway = 3 lanes
• Incident duration prior to project = 1.10 hours
• Incident duration after project implementation = 0.71 hours

Incident Delay = Traffic volume * (Average number of blocked lanes during incidents / total lanes in corridor) * Incident duration

Change in delay = Incident delay without project Incident delay with project
(7,126 vehicle hours 3,277 vehicle hours = 3,849 vehicle hours)

• HC Idle Emissions Factor during incident 19.018 grams/hour
• NOx Idle Emissions Factor during incident 7.230 grams/hour
• PM 2.5 Standard PM idle emissions factor 0.072 grams/hour (2005)
• PM 2.5 Standard NOx idle emissions factor 6.618 grams/hour (2005)

For each pollutant, the Change in delay * Emissions Factor / 1,000 * 111 annual incidents / 260 working days = kg of emissions reduced per day.

• Assume the number of HOV users per day is 10053.72 and the average vehicle occupancy of rideshares is 2.14 persons per vehicle. Also assume the percentage of people attracted to the HOV which:
  • Use transit = 0.14
  • Use transit and previously drove alone= 0.56
  • Use ride share = 0.83
  • Use ride share and previously drove alone = 0.56
• Calculate daily vehicle trip reduction = 10053.72 users * (0.14 * 0.56 + 0.83 * 0.56) * (1 1 / 2.14 persons/vehicle)
• Calculate VMT reduction = 2,929 trips reduced * 20 mile average auto trip length.

Emissions reductions calculated using Mobile6 running emissions factors, assuming a 43 mph running speed on freeways before the project = NOx: 1.22 and VOC 0.53 grams/mile. Speed-based running exhaust emissions factor for the HOV facility, assuming a 51 mph speed = NOx: 1.32 and VOC 0.51 grams/mile. Speed-based running exhaust emissions factor for general purpose lanes, assuming a 43 mph speed = NOx: 1.22 and VOC 0.53 grams/mile.

Calculate change in running exhaust emissions from vehicles shifting from general purpose lanes to HOV lanes. Assume Average Peak Traffic on HOV lanes after project is 783 vehicles/hour and 6 peak hours per day. The HOV length is 20.9 miles. Calculate change in running exhaust emissions from vehicles in general purpose lanes as a result of vehicles shifted away from general purpose lanes. Assume Average Peak Traffic on general purpose lane before project is 10,358 vehicles/hour and the Average Peak Traffic on general purpose lane after project is 10,797 vehicles/hour.

Calculate the reduction in auto start emissions from trip reductions using an auto trip end emissions factor for NOx: 0.39 grams/mile and VOC: 1.25 grams/mile and the trip reductions. Calculate the reduction in auto running exhaust emissions from trip reductions using the emissions factor before project implementation and the vehicle miles reduced.