Recurring Traffic Bottlenecks: A Primer
Focus on Low-Cost Operational Improvements (Fourth Edition)
Chapter 8. Success Stories: How Agencies are Developing Localized Bottleneck Reduction Programs
Successful Localized Bottleneck Reduction Program Development
Unless transportation agencies make low-cost bottleneck improvements an explicit presence, it is likely that they will be overlooked or delayed; either deemed part of a "larger" problem, or unnecessarily postponed to some indefinite out year. There are many ways to combat this.
- Create a unique bottleneck program area. By developing an annual "named" program, agencies can effectively identify, fund, and most importantly, champion low-cost treatments. A stand-alone program also has the added benefit of demonstrating to the public that the agency is actively engaged in fighting congestion.
- Undertake occasional "special projects" to focus on bottlenecks. Low cost bottlenecks can be addressed through occasional "special projects." For example, the Minnesota Department of Transportation (DOT) conducted a one-time special compilation (and legislature-approved funding) of projects meeting certain candidacy requirements, and the Little Rock, Arkansas metropolitan planning organization (MPO) undertook a one-time public solicitation of nagging traffic problems. In much less than one year each organization developed a highly accelerated process for bottleneck identification and prioritization, which led to many effective projects that were implemented in the following years.
- Integrate consideration of low-cost bottlenecks into existing programs. Low-cost bottlenecks can be addressed programmatically even without a special program. By making them part of ongoing planning and processes, the can be part of an agency's congestion arsenal.
Examples of how State DOTs have established localized bottleneck reduction (LBR) programs through an array of approaches are detailed below. The following provide comparisons of how different State agencies have formally incorporated low-cost bottleneck projects into their planning and programming processes. In addition, Figure 19 highlights how the Virginia DOT's Strategically Targeted Affordable Roadway Solutions (STARS) program approaches the LBR problem.
- The California Department of Transportation (Caltrans) does not have a formal bottleneck planning process; rather, bottleneck issues are addressed at the district level as part of the regional planning process. Much of Caltrans' operational planning is guided by the Transportation Management System Master Plan, which sets forth the types of strategies that should be pursued in improving congestion. In much of California's metropolitan areas, traffic congestion is a 24/7 occurrence, and traffic management is a 24/7 job. Bottlenecks are tweaked "in real-time" as part of their Corridor System Management Plans (CSMP), which are developed for some of California's most congested transportation corridors. System monitoring and evaluation is seen as the foundation for the entire process because it cannot only identify congestion problems, but also be used to evaluate and prioritize competing investments. Caltrans does not have a direct funding for bottlenecks, although bottleneck projects are routinely programmed through the CSMP process.
- In Ohio, bottlenecks are part and parcel of the overarching Ohio DOT (ODOT) Highway Safety Program (HSP), which ranks all candidate projects and drives the statewide highway project selection and scheduling process. Beginning in 2002, the ODOT developed a "congestion mapping" division that uses volume/cost (V/C) ratios developed from traffic data recorders and roadway inventory. About the same time, the ODOT administration pushed for an annual process of overlaying congestion index and safety index "hot spots." As a result, congestion hot spots now have a "voice" in the process regardless of crash indices, and congestion-related problems now compete for attention in the HSP listing. Specifically, highway sections with V/C ratios greater than 1.0 are considered "congested" and are added to the listing. Sections with V/C between 0.9 and 1.0, but outside the cities of Columbus, Cincinnati, and Cleveland, are also added. After the ODOT headquarters completes their statewide effort of congestion mapping and safety indexing, the respective District engineers are responsible for developing countermeasures for their top-listed candidate projects. District Safety Review Teams sort projects into three scales—low (less than $100K and quickly implementable), medium ($100K to $5M and one to two years), and high (greater than $5M and necessitating more than two years to implement)—and then compete with other projects having the same scale but in other districts.
- The Minnesota DOT (MnDOT) was originally driven to explore low-cost congestion relief projects because of budgetary restrictions, but soon realized that these projects could be implemented very quickly and, as a bonus, were highly visible and popular with the public. In much less than one year, the MnDOT developed a highly accelerated process for bottleneck identification and prioritization, which led to many effective projects in the following two years. The MnDOT also found that because of lower costs, it could identify multiple locations throughout the region and "spread around" bottleneck reduction projects in a fair and equitable manner. This process consisted of completing a study, which included a five-step process to narrow potential projects into a recommendation list to the State legislature. Evaluation of completed projects produced high benefit/cost ratios, usually greater than 8:1.
- The Maryland State Highway Administration (SHA) has a dedicated program of about $5 million per year for the identification and implementation of low-cost traffic congestion improvements at intersections. The program's genesis tracks to when SHA asked "what can be done if and when a megaproject's 'no-build' alternative is chosen?" The program has been well received by the public and local governments. Projects typically include low-cost projects that can be implemented quickly, such as signal timing upgrades and adding turn lanes and through lanes at intersections. The Maryland SHA has also has had considerable success with projects to improve freeway ramps and merge areas that have reduced congestion bottlenecks at a low cost. Specifically, the Maryland State Highway Administration (SHA) introduced in 2017 the "I‑270 Innovative Congestion Management Plan" for I‑270 between I‑70 (Frederick) and I‑495 (Washington). North of its pass-through of the Washington, D.C. suburb of Montgomery County (out to new town Clarksburg) I‑270 has experienced tremendous growth in the past 15 years where it abuts southern Frederick County in the vicinity of Urbana, Comus, and southern Frederick City. The $105 million plan is the result of a public solicitation for ideas in 2016. The plan encompasses 14 unique roadway improvements ranging from re-configuring on- and off-ramps to correcting existing lane incongruences (using median widening in some cases) and generally tweaking, extending, or creating auxiliary lanes where possible. The plan boasts not to have to increase the current footprint of the facility—or in other words, no widening! It should be noted that I‑270 already has high occupancy vehicle (HOV) lanes and a robust local-express lane configuration that is up to 12 lanes wide through its central portion through north Rockville, Gaithersburg, and Germantown. In addition to the physical corrections, SHA will introduce active traffic management (ATM) strategies in the form of variable speed limits, queue warnings, and adaptive ramp metering. While $105 million may not be everyone's idea of a "low-cost" solution, keep in mind that it is the cumulative cost of 14 fixes, plus the construction and operation of ATM strategies along a 34-mile long corridor. Work is scheduled to be completed prior to 2020.
- In Florida, there is not a "bottleneck" planning process, per se; rather, bottleneck-related issues are addressed as part of the Florida Department of Transportation's (FDOT) standard planning process. The planning process, which is managed by the FDOT Systems Planning Office, begins with needs identification conducted at the district level, then projects are developed and proposed for the Cost Feasible Plan. The Cost Feasible Plan is adopted and projects are ranked for inclusion into the 5-year or 10-year programs. Traffic data and the statewide model are used to identify deficiencies, but it is the responsibility of the districts to identify and resolve hot spots.
- The Washington State DOT (WSDOT) has no direct funding for bottlenecks, but formally recognizes "bottlenecks and chokepoints" in their project planning and development process and devotes a portion of the Washington Transportation Plan (WTP) to them. At the planning stage, the WSDOT considers bottlenecks together with traditional corridor improvements in a category called "Congestion Relief"—bottlenecks do not have their own category for assessment or funding. The Congestion Relief projects are ranked (prioritized) using the benefit/cost ratio and other qualitative factors.
- Additionally, the "Moving Washington" initiative, a special 10-year program, specifically targeted the importance of the short-term low-cost improvements that are the hallmark of LBR projects. In "Moving Washington," Tier 1 projects are "immediate, low-cost, operational fixes." Another aspect of "Moving Washington" relevant for LBR programs is its reliance on performance measurement—not just to identify problems but to assess to the impacts of completed projects. More information on the use of performance measurement by the WSDOT may be found in their "Gray Notebook."
Figure 19. Map. Success spawns success: Virginia's Strategically Targeted Affordable Roadway Solutions (STARS) program spurs Rhode Island to develop its own STARS Program.
(Source: Federal Highway Administration.)
Many transportation agencies have recognized that low-cost treatments can provide effective congestion relief at bottlenecks. A wide variety of improvements have been implemented and many innovative improvements are emerging. Appendix C presents a range of case studies with expanded explanations of how these transportation agencies have used LBR used strategies to improve congestion at bottlenecks.
Want More Information?
The LBR Program has a comprehensive web site with additional information and resources.