Infrastructure Management

Infrastructure Management

Infrastructure management initiatives use infrastructure improvements to enhance freight mobility. Such enhancements are often necessary because both truck size and traffic have increased over the past few decades, making some roadways and buildings obsolete, and unable to support current freight-traffic volumes (Wilbur Smith Associates 2012).

Major Improvements

Initiatives considered for major infrastructure improvements often require large expenditures and fairly elaborate planning efforts.

Initiative 1: Ring Roads for Bypass Traffic

This initiative seeks to shift through-trucks that would otherwise travel through the city to ring roads in the urban periphery. Ring roads only work if they lead to cost savings to the carriers; without proper land use planning they can create excess sprawl, and they require large capital investments, elaborate needs assessments, and impact analyses. Studies to evaluate ring roads should analyze truck traffic, temporal patterns and their environmental impacts, and other complementary measures (PIARC, 2011). The location of traffic generators also needs to be studied, to determine where the proposed ring road and its potential interchanges would most effectively improve mobility.

Initiative 2: New and Upgraded Infrastructure

Initiatives of this type focus on enhancing the geometric design and physical characteristics of current roadways, railways, and intermodal terminals. Market studies must be performed to ensure that investments in these facilities would generate enough intended effects to justify the costs. New or upgraded roads often are considered to address the wider turning radii of trucks (Ogden 1992); trucks unable to make right turns without interfering with oncoming traffic, or cutting across sidewalks; and trucks unable to travel under overpasses (Wilbur Smith Associates 2012), among other issues. Some U.S. examples of this type are the Atlanta freight corridors included in the Georgia Freight Logistics Plan 2010—2050 (Georgia Department of Transportation 2011a).

Railway enhancements face the same obstacles as road-related improvements. Unlike roads and bridges, however, rail infrastructure is primarily owned by private-sector companies, which only make physical improvements if their return on investment can meet expected thresholds. An additional limiting factor is the lack of public funding available to build new or upgraded railways (though federal investments were used in the Alameda Corridor in Los Angeles and the Chicago CREATE project, among others). Nevertheless, new or upgraded railways often are discussed as part of supply chain and logistics improvement plans. An example of this kind of initiative appears in the freight action strategy for the Everett-Seattle-Tacoma Corridor case study in Section 3.

Similarly, upgrades of intermodal terminals could have beneficial effects on urban freight by fostering mode shifts to rail. Given that each mode independently strives to increase its market share in freight activities, cooperation is key to intermodal terminal success, and representatives must commit to the global operation and the overarching benefits that the terminal will return to the system. This is the case of a project the Port Authority of New York and New Jersey (PANYNJ) is pursuing to upgrade the Greenville Yard at the Jersey City waterfront with the main purpose of improving operations and reducing truck traffic in the region. Examples of coordination and required collaborative work of already finalized projects are described in case studies from Kansas City and Los Angeles described in Section 3.

Innovative Design—San Antonio’s US-281 Super Street

Today’s transportation decision makers face increasingly complex issues even as transportation funding has steadily declined. Increasingly, decision makers must do more with less. This is particularly true in urban areas, where the major freight bottlenecks are often located in areas with tight rights-of-way and environmental constraints.

San Antonio’s Challenge

In 2009, the San Antonio region confronted these challenges when the development of a proposed tollway to alleviate congestion on US-281 stalled because of complications in the environmental review process. As congestion increased, freight stakeholders began reaching out to the Texas Department of Transportation (TexasDOT) and the Alamo Regional Mobility Authority to find a short- to mid-term solution to the increasing congestion on US-281 while environmental concerns were being addressed by a larger, long-term solution.

A local engineering firm approached the Alamo Regional Mobility Authority with a proposal to transform one of the most congested portions of the US-281 Corridor into a “Super Street” (see Figure 3). A month later, the $5.2 million project was approved through a combination of funding from the Advanced Transportation District, the city of San Antonio and the American Recovery and Reinvestment Act of 2009 (ARRA, often called the federal Stimulus program). Construction began 1 year later and was completed, despite weather delays, within 10 months (Alamo Regional Mobility Authority n.d.; Purcell 2014).

 

Figure 4: Super Street Illustration Source: FHWA

Source: FHWA 2004
Figure 3. Super Street illustration

 A Super Street is an innovative series of intersection improvements that limit and coordinate signal phases by redirecting left-turn phases. Essentially, minor-road drivers approaching an intersection with a major road physically cannot proceed straight through the intersection. The driver is directed to make a right turn onto the major road, turn around using a crossover, and then turn right onto the minor road (Figure 4). Similarly, left hand turns from the minor road are physically prohibited. All movements of the major road function as a normal intersection (Figure 5).

Each intersection functions as a two-phase signal, versus a traditional multiphase signal that requires significantly more red time; therefore, the Super Street design reduces delay. Additionally, because of the reduced signal complexity, the two signal phases can have different cycle lengths, increasing throughput on the higher-volume major road. Furthermore, the geometric changes to the intersection design also reduce conflict points by 37% compared to a traditional four-leg signalized intersection (FHWA 2004).

Figure 5: Minor Road Movements  Source: FHWA

Source: FHWA 2004
Figure 4. Minor road movements 

Figure 6: Major Road Movements Source: FHWA

Source: FHWA 2004
Figure 5. Major road movements

Although reducing congestion and emissions and improving safety are clear benefits to innovative designs like the Super Street, other challenges could be compounded if this initiative is applied in urban areas. Design considerations need to ensure that trucks turning left from the minor road onto the major road can negotiate the U-turn with ease. According to local freight stakeholders, this has been accomplished in San Antonio, and trucks have been a primary beneficiary of the changes. Additional considerations are needed to maintain traffic flow during the construction process. This is true of most roadway projects, but Super Streets are frequently used in corridors with a tight right-of-way envelope.

In 2011, the US-281 team analyzed the effects of the improved US-281 Super Street Corridor. The team found that delay was reduced during a.m. and p.m. peaks by over 1 million vehicle hours annually (65% and 73% reductions, respectively). This reduction resulted in over $24 million saved annually by users of the corridor. The corridor’s crash rate fell by almost 46%. The $5.2 million investment resulted in a 1 year benefit-cost ratio of 4.7 (Gaston and Gilmer 2011). In 2012, the project was recognized by the American Council of Engineering Companies with an Engineering Excellence Award (Pape-Dawson Engineers 2012).

Innovative solutions will be increasingly necessary growth in both population and freight demand impact U.S. metropolitan areas. Low-cost projects that have a low geographical imprint while producing significant benefits—such as San Antonio’s Super Street—will be a critical to improving freight system performance in metropolitan areas.

Initiative 3: Freight Cluster Development (Freight Village)

Freight cluster developments foster relocation of large freight users, such as distribution centers, manufacturers, truck terminals, and inter-modal facilities to a specific area, typically at the urban fringe. Locating a freight cluster far away from the urban core means that small trucks have to travel longer distances to complete their deliveries increasing vehicle-miles traveled on the last leg of the supply chain. The concept of freight clustering is a relatively recent development in the United States (Smart Growth Network and ICMA 2002), though it is common in Europe. Freight clusters could lead to small reductions in truck traffic given that a portion of the business-to-business freight traffic that normally takes place in the city would take place inside the facility (Allen and Browne 2010). The impact on overall congestion is very small; however, as the business-to-business traffic in the clusters represents a minuscule proportion of the total truck traffic in the city. However, the noise and other negative effects generated inside and around the freight village are great disadvantages for local communities. (For a discussion of success factors in Europe, see European Freight Villages and their Success Factors (Nobel 2011)). Freight clusters require large tracks of land, initial investments, and coordination efforts. The main benefits of freight clusters are to preserve space for freight-intensive activities inside the metropolitan area but outside the central business district.

Minor Improvements

Initiatives associated with minor improvements are relatively less costly, though they still require analysis of the anticipated costs and benefits involved before implementation.

Initiative 4: Acceleration / Deceleration Lanes

Designed to accommodate the acceleration and deceleration profile of trucks, these improvements allow trucks to seamlessly merge into traffic. State and local agencies have made a variety of efforts to deal with issues arising from accelerating levels of truck traffic (Douglas 2003). A comprehensive report covering truck climbing lanes and including real-world experiences, lessons learned from previous implementation, typical issues planners face early in the planning process, and a framework and methods for evaluating the benefits and impacts of truck facilities can be found in the Handbook for Planning Truck Facilities on Urban Highways (Douglas 2004).

Initiative 5: Removal of Geometric Constraints at Intersections

The geometry of intersections in the old sections of large cities poses tremendous challenges to delivery trucks. Although a wholesale redesign of intersections may not be appropriate, it is advisable to improve geometry at selected problem intersections. Restricting access to large trucks may offer a short-term solution, though it may not be appropriate for zones where heavy large-truck traffic is unavoidable. In those cases, a lack of adequate geometric design will significantly impact traffic and safety; removing geometric constraints may therefore be necessary. New developments must ensure appropriate street geometry for truck operations. An example for the implementation of this initiative is presented in the Maspeth Truck Route Redesignation case study in Section 3.

Initiative 6: Ramps for Handcarts and Forklifts

This program involves building ramps on sidewalks to accommodate forklifts or handcarts to improve the efficiency of loading and unloading activities (Ogden 1992). These ramps make it easy for drivers to deliver larger quantities of cargo, which significantly reduces the time spent in parking and loading areas, increasing the areas’ capacity to accommodate freight vehicles. The ramps also allow a truck to park once to unload its goods for a general location, then to break up the load and distribute it to multiple nearby sites, such as having a single drop-off/pick-up location for multiple shippers or receivers, with self-pick-ups and drop-offs using handcarts.

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