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47 From the motor carriers' perspective, the top three policy- Respondents across all modes (excluding motor carriers) or regulatory-related issues that have the most significant indicated that lack of skilled labor (including drivers, crews, impact on freight mobility are: etc.) is the most common operational impact of freight mobil- ity constraints. 1. Inadequate truck parking (determined by land use control) 2. Hours-of-Service regulations (safety regulation) 4.3 Measures or Indicators 3. Speed limit differentials between cars and trucks (safety of Mobility Constraint consideration). The performance measures used in monitoring and iden- tifying freight mobility constraints vary by mode and agency. 4.2.5.2 Major Constraint Types In terms of public- and private-sector perspectives, espe- The predominant type of freight mobility constraint cially for highways, the performance indicators are different. depends on the primary mode of freight movement. Figure 16 State DOTs and MPOs present the public-sector perspectives shows the ranking of the five categories of constraints by for the highway mode and the motor carriers present the modal operators. Technological limitations or inadequacies private-sector perspectives. Public-sector agencies imple- were separated from other operational constraints in order ment improvements to address constraints to facilitate safe, to better understand how technology can improve freight secure, and efficient movement of freight. The private sector, on mobility. It is clear from Figure 16 that technology is a sig- the other hand, uses different measures to monitor and identify nificant factor in freight mobility by all modes. Similarly, constraints to their operations and reacts by taking measures financial limitations are important detractors to improved that minimize the effects of constraints on the safe, secure, and freight mobility. Also, regulatory requirements are consid- efficient movement of freight. The following sections discuss ered to be major constraints affecting freight movement by the measures for highways, railroads, deepwater ports, and all modes. inland waterways. For the motor carrier industry, however, operational limi- tations are the topmost constraints. Physical or infrastructure 4.3.1 Highways deficiencies are not considered the most critical constraints affecting freight mobility. Physical infrastructures are fixed In general, state transportation agencies do not have a well- assets that oftentimes may require major expenditures to defined set of measures or indicators for freight mobility con- expand their capacities. Therefore, for a given transportation straints. There are no defined thresholds such as those that infrastructure system, it would be expected that optimal oper- agencies use for other system-adequacy criteria. Typical high- ations can be achieved through operational and regulatory way agency criteria often considered when selecting projects improvements. include volume/capacity (v/c) ratios greater than 0.9, present Regulatory restrictions Technological limitations/inadequacy Physical capacity Operational limitations Financial limitations 5 4 Weighted Ranking 3 2 1 0 State DOT & MPO Railroads Deepwater Ports Motor Carriers Figure 16. Ranking of constraint types by mode.

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48 serviceability index (PSI) ratings below 3, or structural defi- once overriding impediments such as excessive cost, environ- ciency rating of a bridge below 5. mental constraints, or a lack of community support are con- Some implicit measures or indicators exist in the states sidered. In other words, the criteria are not the sole factors in where freight programs select projects. The criteria by which selecting projects but they play a significant role in ranking they select projects to enhance freight mobility are de facto candidate projects. The factors used by Ohio DOT have at indicators of freight congestion. For instance, Oregon DOT least three criteria directly related to freight mobility. The total measures a proposed project's ability to alleviate a freight factors include: mobility constraint according to whether a proposed trans- portation project: AADT AADTT Reduces transportation costs for Oregon businesses or Volume-to-capacity ratio improves access to jobs and sources of labor Whether the project completes a gap on a statewide eco- Results in an economic benefit to the state nomic corridor Is a critical link connecting elements of Oregon's trans- Crash history portation system that will measurably improve utilization Connectivity to other modes. and efficiency of the system. The criteria of AADT, corridor completion, and inter- Proposed projects are scored by teams of DOT and outside modal connectivity all tend to benefit freight-heavy proj- officials to determine which submitted projects best meet the ects. The intention behind these criteria is to improve freight stated goals. mobility to enhance the state's economic competitiveness. Florida's Strategic Intermodal System Highway Connector Beyond these implied indicators of mobility constraint, the (83) projects are selected based on the relative severity of fac- agency officials across all states in the survey cited what tors such as Annual Average Daily Traffic (AADT), v/c ratios, they consider to be general indicators of freight mobility and the amount of economic activity occurring near a pro- constraints: posed location. Growing congestion, combined with the facil- ity's role of providing access to an important freight generator, Comments from freight industry members about the con- becomes one of the criteria used to select it as a freight mobil- gestion they experience at locations such as steep grades, ity project. congested intersections, and inadequate interchanges Utah DOT (84) uses a set of criteria in identifying its low- Poor turning radii at intersections and driveways cost, quickly implementable freeway improvement projects. Queues of trucks at specific bottlenecks The projects are not specifically freight improvement projects. The lack of regulatory coordination between neighbor- They are general highway improvement projects, but they help ing states in terms of truck inspection, enforcement, and freight because of the high volumes of trucks on Utah high- regulation ways. Trucks compose up to 55 percent of total traffic volumes Decreases in observed operating speeds on the state's Interstate highway system. Utah DOT quali- Decreases in reliability as measured by travel time variability. tatively selects possible locations for improvement based on recommendations from staff, which include factors such as The FHWA Office of Freight Management and Operations observed congestion, the lack of environmental or right-of- sponsors the Freight Performance Measures (FPM) initiative, way constraints, the rapidity of implementation, and the rela- which is managed by the ATRI. Under this initiative, wireless tively low cost of the proposed improvement. A quantitative truck position reports from several hundred thousand trucks ranking is then applied to the proposed projects based on the are collected and analyzed. As a component of the FPM following criteria: research, ATRI analyzed a list of 30 significant U.S. freight bot- tlenecks that were previously identified by FHWA. Actual Average daily traffic truck speeds for these bottlenecks were aggregated to deter- Volume-to-capacity ratio mine the impact of congestion on average truck speeds over a Crash history. 1-year timeframe. Based on these results, the original bottle- necks were re-ranked by severity. These are discussed in Chap- The Ohio DOT (85) selects its major new capacity projects ter 7 of this report. through the Transportation Review Advisory Council. The From the private-sector (i.e., motor carrier industry) per- Council has adopted formal criteria by which it ranks projects. spective, motor carriers utilize several measures to monitor The highest ranked projects are given preference for selection the efficiency of fleet operations, including customer-related