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Background and Key Concepts 17 cles and their drivers. The WRI program is expected to be fully deployed in 2012. WRI technolo- gies could be applied to CMV-only lanes to maximize CMV inspections with minimal roadside investment costs. The roadside components of WRI are envisioned to include equipment, positioned along high- ways, that supports wireless communications to collect safety data message sets from properly equipped CMVs and provide the message sets to the rest of the WRI system. Roadside equipment will include receiver units and mobile enforcement vehicles. CMV-only facilities can be equipped with the necessary roadside units and, because all the traffic consists of CMVs, there is potential for optimal numbers of inspections, constrained only by the level of participation on the part of CMVs (unless equipment is mandated). It should be noted that the separation of trucks and cars may not improve the technical aspects of collecting information by ITS/CVO technologies for enforcement or tolling purposes. Auto- matic vehicle identification (AVI), WIM, and WRI technologies are designed to work in a variety of traffic environments, and would not "work better" technically in CMV-only facilities. However, the separation of trucks and cars would ease the challenges of concentrating trucks in weigh sta- tions or in the outermost lanes of multilane highways in order to capture information from them. In this "captive" environment, few, if any, trucks would be able to avoid size, weight, and/or safety monitoring. As larger numbers of trucks use the CMV-only facilities, enforcement agencies will be able to ensure the compliance of a greater percentage of the CMV population. 2.4 Longer Combination Vehicle Operations Longer combination vehicles (LCVs) were defined by ISTEA as "any combination of a truck tractor and two or more trailers or semi-trailers which operate on the National System of Interstate and Defense Highways with a Gross Vehicle Weight (GVW) greater than 80,000 pounds." ISTEA also allowed grandfathering of existing LCV operations in states where LCVs were allowed prior to June 1, 1991. Because of their larger size and higher weight limit, several potential advantages have been tied to operating LCVs over smaller, lighter commercial vehicles, including increased produc- tivity, reduced truck traffic, reduced cost per unit cargo, and reduced emissions. Similarly, several disadvantages of LCVs also have been associated with the concept and include potential safety issues, potential increases in pavement damage, potential increases in roadside damage (e.g., shoul- ders, curbs, roadside signs), and inadequate rest area parking for truck driver relief. Appendix A provides more detailed information about current LCV configurations and size and weight limits by state. According to the Reason Foundation,19 the existing United States LCV network is fragmented. Although our economy is dependent on global supply chains and efficient goods movement, our internal network for longer commercial vehicle operations does not support the supply chain either at a national level, or between states. While the western U.S. states have the beginnings of an inter- state LCV network, there are no LCV routes that provide connectivity between the western United States and the eastern United States over the Mississippi River. When discussing the use of LCVs and implementation of multistate LCV corridors, it is natural to probe the issue of truck-rail competition. Trucking remains by far the largest freight transporta- tion mode, carrying around 69% of the tonnage for all goods shipped in the United States.20 This 19 R. W. Poole, Jr. and P. Samuel, Policy Study 316, Corridors for Toll Truckways: Suggested Locations for Pilot Projects, Reason Foundation, February 2004. 20 2007 Commodity Flow Survey (http://www.bts.gov/publications/commodity_flow_survey/preliminary_tables_ december_2008/html/table_01.html).

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18 Separation of Vehicles--CMV-Only Lanes is due to the fact that nearly 55% of all freight shipped (measured in tons) travels less than 50 mi, and around 78% travels less than 250 mi.21 Shorter trip lengths with lower lane densities are dom- inated by trucks, while longer trip lengths with higher lane densities are dominated by rail. In recent years, containerizations have turned rail intermodal into more of a long-distance trucking com- petitor; however, whether a shipper chooses to use truck or rail to transport goods depends on sev- eral key factors, including the type of commodity, distance (transit time), service quality, price, and customer preference. Potentially, implementation of LCVs could influence these factors; however, it is not within the purview of this study to investigate them. 2.4.1 LCV Studies Reason Foundation Study In order to mitigate some of the perceived disadvantages of LCV operations noted in the pre- vious section, the Reason Foundation proposes that heavy-duty toll truckways be constructed to complement the existing LCV network.22 The toll truckways would be constructed with the high- est regard for pavement, geometric and safety requirements to allow for use by LCVs. These lanes are proposed to be voluntary to all trucks; however, they would be mandatory for LCVs in non- LCV states. According to the return on investment calculated, these lanes would also be self- funding using the following assumptions: Two (14-ft) lanes each way, Concrete Jersey barrier separation, Separate access/egress ramps, Nodes (make-up/breakdown yards), Variable tolling (all electronic), Voluntary for conventional rigs, mandatory for LCVs, and Located in existing freeway corridors. Although truckers are leery of paying tolls in addition to the other fees and taxes already required, the Reason Foundation concludes that productivity gains made possible by truckways would be so large that trucking companies would be willing to pay tolls to use them. Table 2.4 shows the truck productivity performance of dedicated truckways (with standard truck and LCV operations) compared to mixed freeways with standard truck operations. The semitrailer is the most common long-haul truck in all 48 contiguous states, while the turnpike double is the largest currently operational LCV. The results of this comparison show that signif- icant gains in truck productivity are possible when trucking companies take advantage of dedi- cated truckways. I-35 Trade Corridor Study The I-35 Trade Corridor Study23 reviewed a variety of alternative scenarios aimed at improv- ing local, intrastate, interstate, and international service on I-35 from Texas to Minnesota. One of the alternatives, Trade Focus Strategy, centered on emphasizing the North American Free Trade Agreement (NAFTA) function of the corridor (through the implementation of a partial NAFTA truckway). The alternative proposes to upgrade highways and use truckways to carry 21 2007 Commodity Flow Survey (http://www.bts.gov/publications/commodity_flow_survey/preliminary_tables_ december_2008/html/table_03.html). 22 P. Samuel, R. W. Poole, Jr., and J. Holguin Veras, Toll Truckways: A New Path toward Safer and More Efficient Freight Transportation, Reason Foundation, June 2002. 23 HNTB and Wilbur Smith Associates, I-35 Trade Corridor Study, Recommended Corridor Investment Strategies, Texas Department of Transportation, September 1999.

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Background and Key Concepts 19 Table 2.4. Comparison of truck productivity between truckway and mixed freeway. Mixed Truckway Freeway Truckway Truckway Turnpike Semitrailer Semitrailer Triple Short Double Payload (Pounds) 45,000 45,000 67,500 90,000 Metric Tons 20 20 30 40 100-mi Delivery (2004 Freight Rates) $500 $500 $750 $1,000 Average Speed on the Road 38 mph 60 mph 60 mph 60 mph Miles Driven in 8-h Shift (6 h Driving) 228 mi 360 mi 360 mi 360 mi Revenue from 6 h Payload at 2004 Rates $1,140 $1,800 $2,700 $3,600 Variable Costs $684 $684 $1,007 $1,165 Available for Overhead, Profits, Tolls $456 $1,116 $1,693 $2,435 Extra Earnings from Using Truckways per Shift per N/A $660 $1,237 $1,979 Day Assume Extra Productivity Split Three Ways N/A $220 $412 $660 Shipper Savings on 100-mi Delivery N/A $61/12.2% $76/15.2% $91/18.3% Source: Adapted from Poole, Jr., R.W. and P. Samuel, Toll Truckways: Increasing Productivity and Safety in Goods Movement, Reason Foundation, http://www.fhwa.dot.gov/download/hep/freightplanning/talkingfreight3_16_05bp.ppt. commercial vehicles with larger size and weight limits, where practical, for saving in purchase of additional ROW. The study resulted in the Trade Focus Strategy being recommended with best scores in cate- gories of socioeconomic, environmental, traffic (i.e., operating cost, accident cost savings, and travel time savings), and feasibility. This alternative scored highest in these categories because of the cost-effectiveness of being able to add exclusive lanes for trucks, only where they are required. The study did note that there would be several obstacles to promoting the Trade Focus Strategy through this multijurisdictional study corridor. However, the biggest benefits would be derived by creating a seamless corridor. Some of the key factors that will impact the effectiveness of LCV operations include organizational complexity, regulatory complexity, carrier participa- tion, credentials, and truck size and weight uniformity. Western Uniformity Scenario Analysis The Western Governors' Association requested that U.S.DOT24 assess the impacts of lifting the LCV freeze and allowing harmonized LCV weights, dimensions, and routes among only those western states that currently allow LCVs. The assumption was made that weights would be limited to a maximum gross vehicle weight of 129,000 lbs, and that any benefits achieved would be limited because of the limited scope of the study (i.e., it did not take the whole nation into account). Table 2.5 shows that if LCVs were harmonized in these states, it is predicted that there would be a 76% reduction in travel by conventional five-axle tractor-semitrailers, a 44% reduc- tion of STAA doubles (Surface Transportation Assistance Act of 1982 [STAA] description as five- or six-axle twin trailers with maximum trailer lengths of 28.5 ft) travel, and a 25% reduction in total heavy truck travel. "Because shipments that would divert to LCVs are longer than shipments that would not divert, the decrease in total travel is greater than the decrease in shipments by 24 U.S.DOT, April 2004, Western Uniformity Scenario Analysis: A Regional Truck Size and Weight Scenario Requested by the Western Governors' Association.