Coordinated Highways Action Response Team -Performance and Benefits- Dr. Gang-Len Chang Department of Civil Engineering University of Maryland February, 2012

CHART Evaluation History Data points IncidentsTotal Records ,06838, ,12740, ,51541, ,05544, ,23642, ,58656, ,58555,563

Performance Evaluation & Benefit Estimation Part A: Performance Detection/Response Clearance Incident Duration

Time of System Operations

Data Recorded by TMC Operations Detection sources Location Incident nature Lane-blockage

Distribution of Incident/Disabled Vehicles by Detection Sources in Year 2009 [2008]

Data Recorded by TMC Operations Detection sources Location Incident nature Lane-blockage

Distribution of Incidents/Disabled Vehicles by Road in Year 2009

Data Recorded by TMC Operations Detection sources Location Incident nature Lane-blockage

Distribution of Incidents by Nature in Year 2009

Data Recorded by TMC Operations Detection sources Location Incident nature Lane-blockage

Distribution of Lane Blockages by Major Freeways in Year 2009

Performance Evaluation & Benefit Estimation Part A: Performance Detection/Response Clearance Incident Duration

Distribution of Response Time

Performance Evaluation & Benefit Estimation Part A: Performance Detection/Response Clearance Incident Duration

Comparison of Clearance time in Clearance Time Year 2009 (2008) (minutes) With CHARTWithout CHART Incident Disabled Vehicle TotalIncident Disabled Vehicle Total All Cases with Clearance Time<=2h (19.32) 6.99 (7.05) (12.01) (21.53) 1.31 (2.26) 8.70 (8.77) Cases with Clearance Time>=30s and <=2h (21.98) (10.24) (15.25) (23.87) 5.19 (9.8) (19.27) Cases with Clearance Time >=60s and <=2h (23.22) (11.33) (16.56) (24.89) 8.14 (11.73) (21.01) Cases with Clearance Time >=90s and <=2h (24.08) (12.15) (17.51) (25.48) (12.61) (21.83)

Performance Evaluation & Benefit Estimation Part A: Performance Detection/Response Clearance Incident Duration

Distribution of Incident Durations

Performance Evaluation & Benefit Estimation (cont’d) Part B: Benefits Evaluation Methodology Direct Benefits in year 2009 (2008) Reduction due to CHARTAmountUnit rate Dollars (million) Delay (M veh-hrs) Truck 1.68 (2.09) $20.68/hr truck drivers' cost (43.12) $45.40/hr (cargo's cost) (94.66) Car (29.57) $27.37/hr (car driver's cost) (786.06) Fuel Consumption (M gallons) 6.23 ( ) $2.32/gal (gasoline) $2.50/gal (diesel) (20.98) Emission (tons) HC (413.87) $6,700/ton (36.24) CO 4, (4,648.42) $6,360/ton NO (198.21) $12,875/ton CO 2 57, (58,939.31) $23/metric ton 3 Total (M dollars)1, (981.06)

Benefit Estimation Reduction in Incident Duration Delay reduction Fuel consumption Emissions Secondary incidents Risks at primary incident sites Frequency Impacts

Performance Evaluation& Benefit Estimation (cont’d) Delay Fuel consumption Emission Secondary incidents Risks at primary incident sites Driver assistance

The Methodology for Delay Reduction Duration With SHA Patrol ( minute) Without SHA Patrol ( minute) Duration With SHA Patrol ( minute) 23 Without SHA Patrol ( minute) Comparison of incident duration from One-lane average

The Methodology for Delay Reduction(cont’d) Step 1: distribution of incidents by location I-270 Year 2009

The Methodology for Delay Reduction (cont’d) Step 2: distribution of incidents by lane blockage

The Methodology for Delay Reduction Step 3: select sample incidents for each category

The Methodology for Delay Reduction Step 3: for each sample incident, simulate the entire highway segment Total delay without the sample incident Total delay with the sample incident

The Methodology for Delay Reduction Step 4: Compute the excessive delay due to the sample incidents Delay due to the sample incident (I-Delay) = (T-Delay) w/ – (T-Delay) w/o

The Methodology of Delay Reduction Step 5: with sufficient samples, one can establish the Delay function (I-Delay) = f (Incident duration, traffic volume, No. of lane blockage, total No. of lanes, etc.)

The Methodology of Delay Reduction Step 6: Compute the delay reduction due to CHART operations Current total I-delay Total I-delay without CHART 25% reduction in the average incident duration X-million hours 1/3 X-million hours

Benefit Estimation (cont’d) Delay Reduction Total by CHART Delay Deduction ( M veh-hour)

Performance Evaluation & Benefit Estimation (cont’d) Delay Fuel consumption Emission Secondary incidents Risks at primary incident sites Driver assistance

Benefit Estimation (cont’d) Reduction in fuel consumption Method 1: from the results of simulation Method 2: conversion from the total delay reduction

Method 1 From the results of simulation Method 2 Conversion from the total delay reduction BE: 2. Fuel Consumption

Performance Evaluation& Benefit Estimation (cont’d) Delay Fuel consumption Emission Secondary incidents Risks at primary incident sites Driver assistance

Benefit Estimation (cont’d) Total Delay Reduction HC: grams per hour of delay CO: grams per hour of delay NO: grams per hour of delay Note: The parameters were provided by MDOT in Year 2000

Method 1 From the results of simulation Method 2 Conversion from the total delay reduction BE: 2. Fuel Consumption

BE: 3. Emission Reduction 1.MDOT in Year Literature (DeCorla-Souza, 1998) 3.Energy Information Administration 4.Congressional Budget Office for S. 2191, America’s Climate Security Act of 2007 Total Delay Reduction HC: grams / hour of delay 1 $ 6, 700 / ton 2 HC: grams / hour of delay 1 $ 6, 700 / ton 2 CO: grams / hour of delay 1 $ 6, 360 / ton 2 CO: grams / hour of delay 1 $ 6, 360 / ton 2 NO: grams per hour of delay 1 $ 12, 875 / ton 2 NO: grams per hour of delay 1 $ 12, 875 / ton 2 Fuel Consumption Reduction CO2: lbs/ gallon of gasoline lbs/ gallon of diesel 3 $ 23 / metric ton 4 CO2: lbs/ gallon of gasoline lbs/ gallon of diesel 3 $ 23 / metric ton 4

Performance Evaluation& Benefit Estimation (cont’d) Delay Fuel consumption Emission Secondary incidents Risks at primary incident sites Driver assistance

Benefit Estimation (cont’d) Secondary incidents (2008)

Computation of Reduction on Secondary Incidents -Year 2008 Reported number of secondary incidents: 605 The estimated number of secondary incidents without CHART/MSHA response units (that has resulted in a 27.81% reduction on the average incident duration): 605/( ) = 838 The number of potentially reduced secondary incidents due to the operations of CHART: 838 – 605 = 233

Performance Evaluation& Benefit Estimation (cont’d) Delay Fuel consumption Emission Secondary incidents Risks at primary incident sites Driver assistance

Benefit Estimation (cont’d) Δ Blockage Duration w/ & w/o CHART No. of lane Changes within peak period Number of lane changes at Incident scene Daily Peak-volumes Length of a segment No. of incidents during peak period Lane changes to incident Ratio No.& Type of blockages per peak-hours Per day Number of potential incidents reduced by CHART operations due to effective removal of vehicles Risks at primary incident sites

Reduction of Potential Incidents due to CHART Operations Road Name I- 495/95 I-95I-270I-695I-70I-83 MD- 295 US- 50 Total Mileage No. Potential Incident Reduction

Performance Evaluation & Benefit Estimation (cont’d) Delay Fuel consumption Emission Secondary incidents Risks at primary incident sites Driver assistance

Assistance to Drivers

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