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Truck Drayage Productivity Guide (2011)

Chapter: Chapter 12 - Emissions and Cost Impacts

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Suggested Citation:"Chapter 12 - Emissions and Cost Impacts." National Academies of Sciences, Engineering, and Medicine. 2011. Truck Drayage Productivity Guide. Washington, DC: The National Academies Press. doi: 10.17226/14536.
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Suggested Citation:"Chapter 12 - Emissions and Cost Impacts." National Academies of Sciences, Engineering, and Medicine. 2011. Truck Drayage Productivity Guide. Washington, DC: The National Academies Press. doi: 10.17226/14536.
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Suggested Citation:"Chapter 12 - Emissions and Cost Impacts." National Academies of Sciences, Engineering, and Medicine. 2011. Truck Drayage Productivity Guide. Washington, DC: The National Academies Press. doi: 10.17226/14536.
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Suggested Citation:"Chapter 12 - Emissions and Cost Impacts." National Academies of Sciences, Engineering, and Medicine. 2011. Truck Drayage Productivity Guide. Washington, DC: The National Academies Press. doi: 10.17226/14536.
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Suggested Citation:"Chapter 12 - Emissions and Cost Impacts." National Academies of Sciences, Engineering, and Medicine. 2011. Truck Drayage Productivity Guide. Washington, DC: The National Academies Press. doi: 10.17226/14536.
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Suggested Citation:"Chapter 12 - Emissions and Cost Impacts." National Academies of Sciences, Engineering, and Medicine. 2011. Truck Drayage Productivity Guide. Washington, DC: The National Academies Press. doi: 10.17226/14536.
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Suggested Citation:"Chapter 12 - Emissions and Cost Impacts." National Academies of Sciences, Engineering, and Medicine. 2011. Truck Drayage Productivity Guide. Washington, DC: The National Academies Press. doi: 10.17226/14536.
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Suggested Citation:"Chapter 12 - Emissions and Cost Impacts." National Academies of Sciences, Engineering, and Medicine. 2011. Truck Drayage Productivity Guide. Washington, DC: The National Academies Press. doi: 10.17226/14536.
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Suggested Citation:"Chapter 12 - Emissions and Cost Impacts." National Academies of Sciences, Engineering, and Medicine. 2011. Truck Drayage Productivity Guide. Washington, DC: The National Academies Press. doi: 10.17226/14536.
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Suggested Citation:"Chapter 12 - Emissions and Cost Impacts." National Academies of Sciences, Engineering, and Medicine. 2011. Truck Drayage Productivity Guide. Washington, DC: The National Academies Press. doi: 10.17226/14536.
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88 Overview Purpose Port container drayage is widely recognized as a critical emissions and congestion issue for major container ports, rail intermodal terminals, and the surrounding communities. These issues can be addressed and quantified through use of an emissions and activity model— EPA’s SmartWay DrayFLEET—that accurately depicts drayage activity in terms of vehicle miles traveled (VMT), emissions, cost, and throughput, and can reliably reflect the impact of changing management practices, terminal operations, cargo volume, and diesel truck upgrades. The DrayFLEET Model, a User’s Guide, and a complete report on development of the model are available on the following EPA SmartWay Web site at http://www.epa.gov/ otaq/smartway/transport/partner-resources/resources-drayage.htm and also offers infor- mation about selected drayage emissions reductions strategies, such as chassis pooling and diesel retrofits. Ports and terminals all fulfill the same basic functions, but do so in several different ways and in many detailed variations. DrayFLEET includes model options for all significant drayage func- tions at any port complex, even though those model options may be used rarely. The model includes the following: • Drayage trips of all types to and from marine container terminals, for any reason; • Drayage trips between rail intermodal terminals and marine terminals, and associated bobtail and chassis trips that may not begin or end at the port; and • “Crosstown” trips to reposition empty import containers for export loads, to shift empty marine containers from rail terminals to depots, or to obtain empty containers from depots for export loads. The DrayFLEET Model therefore includes a number of trips and trip types that do not begin or end at port terminals but are necessary to support the overall port container flow. The model does not attempt to account for trips for servicing, fuel, and repair; side trips for meals, rest, or errands; and trips made on non-port assignments such as domestic rail inter- modal drayage. Because volumes vary from year to year and month to month while movement patterns tend to persist, the model relies primarily on pattern indicators and proportions to estimate drayage trips, times, and mileages. This approach facilitates forward-looking or “what if” analyses of drayage activity and emissions with growing cargo volumes. C H A P T E R 1 2 Emissions and Cost Impacts

Emissions and Cost Impacts 89 Model Approach The model allows users to input data values typical of their port or terminal (such as annual TEU or distance to major customers) to create a base case activity and emissions estimate. The user can then make further input choices to create “what if” scenarios. DrayFLEET is distributed as a generic model for a hypothetical container port handling 2 million annual TEU. There are three basic steps to setting up the model for application to a specific port or terminal, as follows: 1. Input the port or terminal’s specific base case default values, 2. Reset the default output values to create a port-specific base case, and 3. Create scenarios as required. The DrayFLEET Model incorporates an activity-based approach. Each significant drayage trip type or activity is assigned a time and distance value. That value may be a precise empirical mea- surement, a weighted average, or an industry rule of thumb, depending on the data available. The model takes the total container volume handled by the port or terminal in question and determines the volume and mix of drayage activities required or implied. The time and VMT for those activities are tallied to develop port or terminal total drayage minutes and VMT. For input to the emissions model, each activity time is divided into minutes by driving cycle component—idle, creep, transient, and cruise. Drayage time and miles also become inputs to the cost and capacity portions of the model. The drayage activity cycle is made up of idling, queuing/creeping, and driving in various combinations. The activity modeling approach includes several key features as follows: • Port-specific or generic default values for every variable and input; • Accommodation of user inputs that differ from defaults; • A streamlined user “front end” to facilitate primary inputs and “what if” scenarios; • An embedded flow chart of port-related container trips to account for all significant movements; • Activity tally sheets to capture default or user-specified factors for over-the-road drayage, terminal trips, etc.; and • Summary activity model outputs in minutes by duty cycle to serve as emissions model inputs. Figure 12–1 gives an overview of the model structure and the flow of information. CONTAINER DISTRIBUTIONI I I I DRAYAGE ACTIVITY SHEETS TIVITY S EETS PRIMARY OUTPUTS: DRAYAGE VMT MINUTES BY DUTY CYCLE I : I OPTIONAL DETAILED INPUT FACTORS I I I EMISSIONS MODELI I PRIMARY INPUTS WORKSHEETI I PORT /GENERIC DEFAULTS / I USER INPUTS I OR Figure 12–1. DrayFLEET model structure.

90 Truck Drayage Productivity Guide Input categories include the following: • Port and terminal information (e.g., TEU, import/export balance); • Default/scenario operational factors (e.g., transaction times); • Management strategies (e.g., on-dock rail, automated gates); and • Drayage tractor fleet and technologies (e.g., diesel engine retrofits). Outputs provided include the following: • Activity outputs (e.g., trip legs and VMT); • Duty cycle outputs (e.g., idle, creep, transient, and cruise minutes); and • Comparison charts to illustrate changes from defaults. Figure 12–2 shows the primary inputs worksheet. This worksheet (shown in its entirety) has five sections covering key input values, port or terminal management initiatives, activity outputs, emissions and cost outputs, and a note section to identify the model application and scenario. For each of the primary inputs there is a default value and a scenario value. The model uses the default value unless it is superseded by a different user entry in the scenario columns. The key port and terminal inputs specify the overall volume and pattern of container movements. The generic model version offers the user convenient starting points to avoid having to input every variable. The user can replace other defaults with specific scenario information as available. Emissions Estimates DrayFLEET calculates emissions by combining the amount of time that trucks spend within var- ious modes of operation (idle, creep, transient, and cruise) with EPA emissions rate data specific DrayFLEET Version 1.0d of 06/10/2008 Primary Inputs Default Scenario Port Port Terminal(s) Calendar Year 2007 Scenario Annual TEU 2,000,000 2,000,000 Average TEU per Container 1.75 1.75 Inbound Share 50% 50% Inbound Empty Share 5% 5% Date Outbound Empty Share 25% 25% Rail Intermodal Share 25% 25% Activity Outputs Default Scenario Change % Change Marine Terminals Annual Activity Average Inbound Gate Queue Minutes 15 15 Number of Drayage Trip Legs 3,498,452 3,498,452 0 0.0% Average Marine Terminal Min. per Transaction 30 30 Drayage Trip Legs per Container 3.1 3.1 0.0 0.0% Rail Terminals Total Drayage VMT 65,706,753 65,706,753 0 0.0% Weighted Average Miles from Port 5 5 Drayage VMT per Container 57.5 57.5 0.0 0.0% Average Inbound Gate Queue Minutes 5 5 Fleet Required (FTE Tractors) 1,224 1,224 0 0.0% Average Rail Yard Min. per Transaction 15 15 Annual Duty Cycle Totals Container Depots Idle Hours 1,869,294 1,869,294 0 0.0% Weighted Average Miles from Port 2 2 Creep Hours 994,223 994,223 0 0.0% Share of Empties Stored at Depots 10% 10% Transient Hours 572,700 572,700 0 0.0% Container Shippers/Receivers Cruise Hours 1,506,026 1,506,026 0 0.0% Weighted Average Miles from Port 25 25 Total Drayage Hours 4,942,243 4,942,243 0 0.0% Weighted Average Crosstown Trip Miles 10 10 Drayage Hours per Container 4.3 4.3 0.0 0.0% Cost Factors Average Drayage Labor Cost per Hour 12.00$ 12.00$ Emissions Outputs Default Scenario Change % Change Average Diesel Fuel Price per Gallon 4.00$ 4.00$ Pollutant (annual tons) HC 53 53 0.00 0.0% Initiative Inputs Default Scenario CO 298 298 0.00 0.0% Port/Terminal Initiatives NOx 1,108 1,108 0.00 0.0% Stacked Terminal (% stacked) 0% 0% PM10 37 37 0.00 0.0% On-Dock Rail (% of rail on-dock) 0% 0% PM2.5 31 31 0.00 0.0% Automated Gates (% of gate transactions) 0% 0% CO2 88,497 88,497 0 0.0% Extended Gate Hours (% off-peak, 50% max) 0% 0% Fuel Use and Total Cost Container Info System (% used) 0% 0% Fuel - Gallons 7,909,626 7,909,626 0.0 0.0% Virtual Container Yard (% available) 0% 0% Total Drayage Cost 159,451,797$ 159,451,797$ -$ 0.0% Neutral Chassis Pool (% used) 0% 0% Drayage Cost per Container 140$ 140$ -$ 0.0% SmartWay DrayFLEET Version 1.0 Primary Inputs & Outputs 2007 Figure 12–2. Primary inputs worksheet.

Emissions and Cost Impacts 91 to those operating modes for a given fleet age distribution. Loaded and empty emissions are calcu- lated separately. The emissions rate data are already part of the DrayFLEET Model and the amount of time spent within each mode comes directly from the activity module. Four operating modes are included in the DrayFLEET Model: idle, creep, transient, and cruise. The activity portions of the model yield estimates of minutes spent by drayage tractors in each of these modes. As of September 2010, the emissions portion of the model uses a mode conver- sion factor to bridge the gap between the detailed drayage activity model output and the emis- sions factors in MOBILE 6.2. Subsequent versions of the model will be updated to use the current EPA emissions methodologies. Port-Area Emissions Estimates The percentage impact of these or any emissions or activity changes depends on the context. Emissions inventories typically define a target area in the near vicinity of the port, consistent with the limited ability of the port or the terminal operators to affect drayage activities outside the port area. DrayFLEET, on the other hand, captures the full range and impact of port-related drayage activity at any distance. To do so, DrayFLEET uses weighted average distances to off-dock rail terminals, container depots, and—most critically—shippers and receivers. Rail ter- minals and container depots are typically within a few miles of the port, but shippers and receivers can be spread out over a broad region. A major limitation on the percentage impact of marine terminal efficiency or emissions mea- sures is the share of all drayage activity associated with the marine terminals. Figure 12–3, extracted from the generic model activity summary, highlights the trips, miles, and hours in the various major activity categories. The marine terminal accounts for about 76% of the trips, but only 25% of the miles and 49% of the hours. Shipper/receiver movements account for 41% of the trips, but 67% of the miles and 41% of the hours. The miles and hours generated by drayage trips to and from distant customers can outweigh and obscure the impacts of port-area changes. Figure 12–4 provides an example of this relation- ship. In this figure, the 25-mile default value for the weighted average trip to shippers and receivers was changed to 5 miles. That change reduced drayage VMT by 52.9%, drayage hours by 26.7%, emissions and fuel use by 41.9% to 45.4%, and cost by 29.3%. In other words, the additional 20 miles (one way) to shippers and receivers accounted for over half the drayage miles, 26.7% of the hours, 41.9% to 45.4% of the emissions and fuel, and 29.3% of the cost. Table 12–1 compares the drayage hours by category for a 25-mile scope and a 5-mile scope. In addition to the overall reduction in total and average hours, the proportions of idle, creep, Activity Group Number of Trips Distance (Miles) Total (hours) Marine Terminal 2,917,414 17,012,538 2,533,308 Inter-Terminal 5,714 22,857 878 Off-Dock Rail Terminal 346,909 1,367,673 164,735 Container Depot 69,917 154,697 27,401 Shippers & Receivers 1,811,250 45,589,163 2,136,895 Crosstown Trips 426,588 4,267,065 340,110 Other Port Trucks - - - Net Total* 3,826,235 68,413,994 5,203,327 *Subtotals and total are corrected to remove double-counting of marine terminal trips. Figure 12–3. Marine terminal vs. shipper/receiver activity.

92 Truck Drayage Productivity Guide transient, and cruise hours shift noticeably. With a 25-mile scope, 30% of the hours are spent in cruise mode. Activity within 5 miles of the port, however, is dominated by idling at 45% of the total hours. Initiatives and Technology Impacts Modeling the emissions impacts of port and terminal management initiatives (such as neu- tral chassis pools and automated gates) was a major reason for developing DrayFLEET. Likewise, DrayFLEET is intended to estimate the impacts of truck and engine technology such as diesel particulate filters or idling controls. The EPA SmartWay Program offers freight carriers technical and financial information on a range of truck and engine technologies and practices designed to conserve fuel and reduce emis- sions. Many of the applicable options have been built into DrayFLEET, as shown in Figure 12–5. DrayFLEET Version 1.0E of 06/26/2008 Primary Inputs Default Scenario Port Generic Port Terminal(s) All Calendar Year 2007 Scenario Five-mile versus 25-mile Limits Annual TEU 2,000,000 2,000,000 Average TEU per Container 1.75 1.75 Inbound Share 50% 50% Inbound Empty Share 5% 5% Date 6/26/2008 Outbound Empty Share 25% 25% Rail Intermodal Share 25% 25% Activity Outputs Default Scenario Change % Change Marine Terminals Annual Activity Average Inbound Gate Queue Minutes 15 15 Number of Drayage Trip Legs 3,826,235 3,826,235 0 0.0% Average Marine Terminal Min. per Transaction 30 30 Drayage Trip Legs per Container 3.3 3.3 0.0 0.0% Rail Terminals Total Drayage VMT 68,413,994 32,188,994 -36,225,000 -52.9% Weighted Average Miles from Port 5 5 Drayage VMT per Container 59.9 28.2 -31.7 -52.9% Average Inbound Gate Queue Minutes 5 5 Fleet Required (FTE Tractors) 1,756 1,286 -469 -26.7% Average Rail Yard Min. per Transaction 15 15 Annual Duty Cycle Totals Container Depots Idle Hours 1,957,060 1,725,478 -231,582 -11.8% Weighted Average Miles from Port 2 2 Creep Hours 1,089,182 991,532 -97,651 -9.0% Share of Empties Stored at Depots 10% 10% Transient Hours 597,318 339,489 -257,828 -43.2% Container Shippers/Receivers Cruise Hours 1,559,766 755,790 -803,977 -51.5% Weighted Average Miles from Port 25 5 Total Drayage Hours 5,203,327 3,812,289 -1,391,038 -26.7% Weighted Average Crosstown Trip Miles 10 10 Drayage Hours per Container 4.6 3.3 -1.2 -26.7% Cost Factors Average Drayage Labor Cost per Hour 12.00$ 12.00$ Emissions Outputs Default Scenario Change % Change Average Diesel Fuel Price per Gallon 4.00$ 4.00$ Pollutant (annual tons) HC 55 32 -23.34 -42.3% Initiative Inputs Default Scenario CO 311 181 -130.12 -41.9% Port/Terminal Initiatives NOx 1,154 637 -517.58 -44.8% Stacked Terminal (% stacked) 0% 0% PM10 38 21 -17.27 -45.4% On-Dock Rail (% of rail on-dock) 0% 0% PM2.5 32 18 -14.60 -45.4% Automated Gates (% of gate transactions) 0% 0% CO2 145,037 79,582 -65,455 -45.1% Extended Gate Hours (% off-peak, 50% max) 0% 0% Fuel Use and Total Cost Container Info System (% used) 0% 0% Fuel - Gallons 12,963,067 7,112,838 -5,850,228.3 -45.1% Virtual Container Yard (% available) 0% 0% Total Drayage Cost 185,045,398$ 130,800,961$ (54,244,438)$ -29.3% Neutral Chassis Pool (% used) 0% 0% Drayage Cost per Container 162$ 114$ (47)$ -29.3% SmartWay DrayFLEET Version 1.0 Primary Inputs & Outputs 2007 Figure 12–4. Five-Mile scenario versus 25-mile default. Category Idle Hours 1,957,060 38% 1,725,478 45% Creep Hours 1,089,182 21% 991,532 26% Transient Hours 597,318 11% 339,489 9% Cruise Hours 1,559,766 30% 755,790 20% Total Drayage Hours 5,203,327 100% 3,812,289 100% Drayage Hours per Container 4.6 3.3 Default - 25-Mile Trips Port Vicinity - 5-Mile Trips Table 12–1. Scope comparison.

These measures have different impacts on drayage emissions and fuel use, depending on which combination of options is applied and how widely they are implemented across the fleet. Data Sources The primary sources for DrayFLEET Model input data are the port authority, the marine ter- minals, and the other activity centers (off-dock rail terminals, container depots, and shipper/ receiver facilities). Port Data Port authorities ordinarily track the inbound (import) and outbound (export) volumes of loaded and empty containers. These data are almost always kept in TEU, but also may be avail- able in containers. Data on empty container flows may not be as readily available and sometimes may not be as accurate. Marine Terminal Data Container terminal operating systems collect information on gate activity. Movement of loaded containers, empty containers, and bare chassis to and from the marine terminals tends to be well documented, but some reconciliation between interchange documentation and gate records may be required. In practice, the accuracy and accessibility of gate information will vary with the accuracy of inputs, the rigor with which the system is maintained, and the experience of those accessing the data. Rail Terminal Data Likewise, comprehensive data on gate transactions is kept by rail intermodal terminal opera- tors and their systems, of which OASIS is a leading example. Although rail terminals are owned and ultimately controlled by the railroads, they are ordinarily operated by contractors. Clerical functions at the gates and any automated systems are supervised by the contractor, as is data Technology Retrofits 50% 50% 50% Idle Reduction % reduction in idle 50% Fuel Conservation % of fleet 50% % of fleet 50% % of fleet 50% lbs of weight saved 2,000 % of fleet 50% % of fleet 50% % of fleet 50% % of fleet 50% % of fleet 50% % of eligible fleet retrofit % of eligible fleet retrofit % of eligible fleet retrofit Idling Control Strategies Single-Wide Tires Tare Weight Reduction Low Friction Engine Lubricant Direct Drivetrain Speed Management Policy (55 mph) Flow-Through Filter Particulate Filter/Trap Oxidation Catalyst Low Friction Drive Train Lubricant Single Axle Drive (vs. Dual Axle) Automatic Tire Inflation Figure 12–5. DrayFLEET technology and strategy options. Emissions and Cost Impacts 93

94 Truck Drayage Productivity Guide input. Although gate transaction data might be obtained through a railroad representative, issues of accuracy, completeness, and interpretation may need to involve the contract operators. Container Depot Data Most container depots are privately operated, either by one of a few regional or national companies, or by local entrepreneurs. They store containers for ocean carriers and leasing companies. Depots also maintain and repair containers, but the activity model does not dis- tinguish trips for repair or maintenance from trips for storage. Container depots keep elec- tronic records of their transactions, but as private companies, their cooperation in providing data is strictly voluntary. Shipper and Receiver Data Obtaining reliable distance and volume information for shipper (export) and receiver (import) trips can be a considerable challenge. The actual locations and container volumes are known only to the shippers and consignees themselves, and perhaps to the drayage firms that serve them. Port marketing and sales departments can be a source of insight on the actual locations of port customers and for customer contact information. Street Turn and Crosstown Data Ordinarily, there is no organization that keeps data on street turns and crosstown trips, so esti- mates are required. Two factors are at stake: the frequency of street turns (reuse of import con- tainers for export loads) and other crosstown trips, and the distance commonly traveled. In both instances, major drayage firms would be the best sources for estimates. National Drayage Cost and Emissions Estimates In NCFRP Project 14, the study team used the EPA SmartWay DrayFLEET Model to estimate vehicle activity associated with port drayage, its cost, and resulting emissions. In 2008, U.S. ports handled a total of 22,597,601 TEU in about 13 million individual containers. The DrayFLEET Model was used to estimate the operational, financial, and environmental costs of container drayage at the nation’s ports. The DrayFLEET Model was configured with a weighted average drayage distance of 5 miles and no waiting time at customer locations. These modifications effectively restrict the model to a 5-mile working range around the port terminals. This step was necessary to focus the analysis on differences in terminal and port-area operations rather than to have the potential improve- ments observed by over-the-road operations. The 13 million containers required an estimated 41.6 million drayage trip legs, an average of 3.2 per container. Those trips required an estimated 39.1 million driver and tractor hours to cover 326 million miles. The model estimates that 45% of the drayage hours in the vicinity of the ports were spent idling, which is generally consistent with most driver survey results. About 26% of the hours were spent in “creep” mode, essentially low-speed, stop-and-go operation typical of queuing or in- terminal operation. This allocation highlights the amount of time—nearly 18 million hours annually—that drayage drivers and their tractors spend idling. In those operating hours, port drayage tractors burned an estimated 69.9 million gallons of diesel fuel and emitted 782,613 tons of CO2, the major greenhouse gas impact (see Table 12–2).

As Table 12–2 shows, those tractors emitted an estimated 7,678 tons of NOx and 149 tons of PM2.5, as well as other criteria pollutants. The estimated total port-area drayage cost was $1.44 billion, an average of about $112 per con- tainer. That total included about $210 million in fuel costs at $3 per gallon, which accounted for 4.6% of the total cost. Impacts of Drayage Bottlenecks DrayFLEET can be used to estimate the impacts of bottlenecks and sources of delay identified in the study. As an illustration, Table 12–2 also summarizes the results of national scenario esti- mates made in the course of NCFRP Project 14. Terminal and Queue Time Reduction The default national model was configured with a 60-minute average port turn time divided into 20 minutes of queuing outside the gate and 40 minutes inside the terminal. Reduction of the average terminal time from 40 minutes to 30 minutes would reduce the total time required by about 3 million hours (8.1%), and the fuel burned by about 1 million gallons (2.1%). CO2 emissions would also drop by 2.0%. NOx would drop by 160 tons (2.09%) and PM 2.5 by 3 tons (1.9%). The annual cost savings would be about $79 million. If the average queue time were reduced from 20 minutes to 10 minutes, the impacts would be similar (Table 12–2), although the fuel and emissions savings would be greater due to the greater reduction in the relatively inefficient and “dirty” stop-and-go queuing operations. If both the terminal time and the queue time were reduced by 10 minutes the impacts would be additive. Trouble Ticket Reduction In NCFRP Project 14, the study team found that experienced draymen appear to average about 3% trouble tickets (exceptions), although the overall average was 5%. Reducing the incidence of Hours Fuel CO2 NOx PM 2.5 CostScenario (million) (million gal.) (tons) (tons) (tons) (million) 2008 National Default 39.1 69.9 782,613 7,678 149 $1,440.00 30 vs. 40 Minute Terminal Time (3.2) (1.4) (15,652) (160) (3) $(79) Change -8.1% -2.0% -2.0% -2.1% -1.9% -5.5% 10 vs. 20 Minute Queue Time (2.7) (2.0) (21,913) (225) (4) $(69) Change -6.8% -2.8% -2.8% -2.9% -2.7% -4.8% 3% vs. 5% Trouble Tickets (0.3) (0.1) (1,632) (17) (0) $(8) Change -0.8% -0.2% -0.2% -0.2% -0.2% -0.5% 0% vs. 5% Trouble Tickets (0.8) (0.3) (3,913) (42) (1) $(20) Change -2.0% -0.5% -0.5% -0.5% -0.5% -1.4% Idling Control - 50% - (5.9) (65,739) (450) (8) $(17) Change 0.0% -8.4% -8.4% -5.9% -5.4% -1.2% 100% vs. 20% Neutral Pools (0.8) (0.3) (3,913) (42) (1) $(20) Change -2.0% -0.5% -0.5% -0.6% -0.5% -1.4% Trucker-Supplied Chassis (6.1) (4.4) (49,305) (503) (9) $(137) Change -15.6% -6.3% -6.3% -6.6% -6.1% -9.5% Combined Strategies (14.5) (9.9) (111,050) (979) (18) $(202) Change -37.1% -14.2% -14.2% -12.8% -11.8% -14.0% Table 12–2. DrayFLEET modeling results. Emissions and Cost Impacts 95

96 Truck Drayage Productivity Guide trouble tickets from 5% to 3% would save about 300,000 hours of drayage time, 100,000 gallons of fuel, 17 tons of NOx, and $8 million dollars in port-area drayage costs. If trouble tickets could be completely eliminated (0%), the savings would be greater yet: 800,000 drayage hours, 300,000 gallons of fuel, 42 tons of NOx, 1 ton of PM 2.5, and $20 million. These potential savings are therefore the estimated costs of trouble tickets. Idling The estimated 46% of drayage time spent idling, which accounts for nearly 18 million hours nationwide, suggests large potential benefits from idling controls or hybrid truck tractors that would neither burn fuel nor emit pollutants when they were not moving. If the tractor engines could be turned off for half of the time they are now estimated to be idling, yearly fuel use would drop by 5.9 million gallons. Greenhouse gasses (CO2) would be reduced by over 65,000 tons, NOx would decline by 450 annual tons, and PM 2.5 would decline by 8 tons in port areas. The fuel saving would reduce drayage cost by about $17 million annually. The hours required would not decline, but for half the 18 million idling hours, the engines would be off. Chassis Logistics The EPA SmartWay Program has identified chassis pooling as a promising strategy for improv- ing drayage efficiency and reducing emissions. The DrayFLEET modeling bears out this conclu- sion. With an assumed 50% of the containers being stacked in the terminals, raising the default 20% usage of neutral chassis pools to 100% usage yielded almost exactly the same benefits as elim- inating trouble tickets (Table 12–2). The benefits of neutral chassis pools show up in the model mostly as reduced chassis search time. A shift to trucker-supplied chassis yielded the greatest benefits of the individual scenarios shown in Table 12–2. Modeling a trucker-supplied chassis system entailed the following: • Raising the share of containers stacked from 50% to 100%, • Eliminating chassis search time and bare chassis drop-off time, • Reducing overall in-terminal time by 10 minutes per move, • Reducing average gate transaction times from 5 minutes to 3 minutes, • Reducing average queue times from 20 minutes to 15 minutes, and • Adding $2 per move (about $6 per day) to drayage costs to account for truckers’ chassis supply costs. Although these modeling changes are necessarily inexact approximations of an emerging system, they indicate the kinds of pervasive changes that can be expected. The estimated benefits of trucker-supplied chassis include an annual savings of over 6 mil- lion hours of driver and tractor time, over 4 million gallons of fuel, and $137 million in drayage costs. CO2 emissions would decline by an estimated 49,305 tons. Port-area NOx would decline by an estimated 503 tons, and PM 2.5 by 9 tons. Combined Impacts and Benefits Combining all of the scenarios yields an estimate of the improvements possible if queuing were to be minimized, trouble tickets eliminated, idling control implemented on half the fleet, and the transition to trucker-supplied chassis completed. As Table 12–2 indicates, the benefits would be substantial and indicate the value of progress toward drayage bottleneck solutions as follows: • A 37.1% reduction in total hours—14.5 million hours of driver and tractor time annually, • A 14.2% reduction in fuel use—an annual savings of nearly 10 million gallons of diesel fuel,

• A 14.2% reduction in CO2, • A 12.8% and 11.8% reduction in NOx and PM 2.5, respectively and • A 14.0% annual cost savings—over $200 million. It is likely that efficiency improvements on this scale would have additional benefits not cap- tured in the DrayFLEET Model. For example, there probably would be an opportunity to retire the oldest, least efficient, and most polluting drayage tractors. It is likely that marine terminal operators would realize associated savings in labor and CY operations, as well as gaining capacity by freeing up land presently being used to store chassis. Implications The cost and emissions estimates derived from DrayFLEET indicate the magnitude of the drayage issue and the value of potential solutions, together or separately. The United States has made tremendous progress in reducing vehicular emissions, but further progress has become increasingly difficult and costly. Port communities face serious technical, economic, and politi- cal challenges in attempting to reduce or control the growth of congestion and emissions from port drayage. The estimates derived for this study indicate the potential scope of improvement achievable through process improvement, reduction of exceptions, and a smooth transition to driver-supplied chassis. Each port area has a different pattern and volume of drayage options, and thus a different potential for improvement through the measures identified in this guidebook. DrayFLEET can be used in local and regional planning efforts to determine the following: • The starting point for port-area and regional drayage activity, cost, and emissions (although DrayFLEET is not a substitute for a complete emissions inventory); • The impact of local practices, bottlenecks, and delays on costs and emissions; and • The potential VMT, cost, fuel, labor, time, and emissions benefits of potential drayage effi- ciency improvements. DrayFLEET (or an equivalent model) can therefore become a valuable tool in investigating and comparing possible solutions and establishing their value to all concerned. The critical factor in using DrayFLEET for this purpose is realism, the close correspondence between model inputs and relationships and actual truck and terminal operations. Time invested up front to obtain accurate input data and to make the appropriate model inputs and adjust- ments yield dividends in credibility within the port and drayage community. Emissions and Cost Impacts 97

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TRB’s National Cooperative Freight Research Program (NCFRP) Report 11: Truck Drayage Productivity Guide is designed to help improve drayage productivity and capacity while reducing emissions, costs, and port-area congestion at deepwater ports.

The guide includes suggestions designed to help shippers, receivers, draymen, marine terminal operators, ocean carriers, and port authorities address inefficiencies, control costs, and reduce associated environmental impacts of truck drayage.

The guide identifies and quantifies the impacts of bottlenecks, associated gate processes, exceptions (trouble tickets), chassis logistics, congestion, and disruption at marine container terminals. The impacts are described in terms of hours, costs, and emissions that were estimated using the Environmental Protection Agency’s DrayFLEET model.

A CD-ROM, which contains the final report on the development of NCFRP Report 11 and its appendices, is included with the print version of NCFRP Report 11.

The CD-ROM is also available for download from TRB’s website as an ISO image. Links to the ISO image and instructions for burning a CD-ROM from an ISO image are provided below.

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CD-ROM Disclaimer - This software is offered as is, without warranty or promise of support of any kind either expressed or implied. Under no circumstance will the National Academy of Sciences or the Transportation Research Board (collectively “TRB’) be liable for any loss or damage caused by the installation or operations of this product. TRB makes no representation or warranty of any kind, expressed or implied, in fact or in law, including without limitation, the warranty of merchantability or the warranty of fitness for a particular purpose, and shall not in any case be liable for any consequential or special damages.

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