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OCR for page 19
SECTION V Description of Strategies Objectives The main goal of this guide is the reduction of fatal and severe injury traffic crashes in which speeding or inappropriate speed is a factor. As is the case with most of the guidance in the AASHTO Strategic Highway Safety Plan, effectively addressing these types of collisions involves an interdisciplinary approach; a combination of education, enforcement and engineering measures will often be needed to obtain measurable improvements in safety. Speeding-related fatalities can occur when drivers are traveling at speeds clearly in excess of the appropriate speed. Fatalities can also result when the selected speed is legal, yet local conditions warrant a lower speed. This guide suggests several objectives for addressing the problem of speeding and inappropriate speed choice. Specific objectives include improvements in procedures for setting speed limits, driver education programs, speed enforcement programs and engineering features of the roadway environment. Exhibit V-1 lists the objectives and the related strategies for severe crashes that involve speeding or inappropriate speeds. Set appropriate speed limits--Setting speed limits to reflect the surrounding context of the roadway and that meet with driver expectations can help improve driver respect for speed limits. Speed limits that appear inconsistent may be ignored by the majority of drivers and this may contribute to lack of respect for speed limit and other traffic laws. Heighten driver awareness of speeding-related safety issues--Informing drivers of the risks--both to themselves and to other road users--associated with speeding is intended to encourage drivers to obey speed limits and drive at speeds safe for the roadway environment. Improve the effectiveness of speed enforcement efforts--Many crashes are caused or aggravated by drivers' noncompliance with traffic control devices or traffic laws. Effec- tiveness of enforcement can be increased if drivers perceive there is a significant chance they may be cited for speeding and may be given a hefty fine. Visible conventional or automated enforcement programs, increased fines for repeat offenders, and upholding of citations and levying of fines by courts can increase drivers' perceptions of the enforcement-related risks of speeding. Communicate appropriate speeds through use of traffic control devices--Information on appropriate speeds, including permanent speed limits, variable speed limits, and warning speeds, needs to be conveyed clearly to drivers and at appropriate locations. Pavement markings can be used to encourage drivers to proceed at appropriate speeds without actually posting the speed limit. Even though drivers have the responsibility to drive at a safe speed, they need to be able to receive cues from the roadway environment as to what that safe speed is. V-1

OCR for page 19
SECTION V--DESCRIPTION OF STRATEGIES Ensure that roadway design and traffic control elements support appropriate and safe speeds--Geometric design features of roadway sections and intersections, and operation of traffic signals, need to reflect the speeds expected of drivers. For example, roadway designs sensitive to the context in which they will be located can encourage appropriate speed choices by drivers. Geometric elements which affect operating speeds, such as horizontal and vertical curves, can be designed in combinations to encourage appropriate speeds. Intersection types and designs should be appropriate for the context of the roadway. Providing a proper signal co-ordination through inter- sections along a corridor can create uniform speeds and reduce the need for drivers to stop at the intersections. Ultimately, the goal toward which the objectives and strategies are directed is to improve safety for all road users by reducing the incidence of speeding and inappropriately high speeds. The strategies discussed in this section combine the elements of education, enforcement, and engineering. Strategies are suggested recognizing that, with few exceptions, programs that depend on only one of these elements are usually not as successful as those which incorporate a range of elements. Some strategies are aimed at general cultural and behavioral attributes of the driving public, while others are targeted at specific high-risk locations or portions of the population. The strategies listed in Exhibit V-1, which are EXHIBIT V-1 Objectives and Strategies for Addressing Speeding-Related Fatalities Objectives Strategies A. Set appropriate speed limits A1 Set speed limits which account for roadway design, traffic, and environment (T) A2 Implement variable speed limits (T) A3 Implement differential speed limits for heavy vehicles if appropriate (High Speed Only) (T) B. Heighten driver awareness B1 Increase public awareness of the risks of driving at unsafe of speeding-related safety issues speeds (T) B2 Increase public awareness of potential penalties for speeding (T) B3 Increase public awareness of risks of not wearing seatbelts (T) B4 Implement neighborhood speed watch/traffic management programs (Low Speed Only) (T) B5 Implement Safe Community Programs (T) C. Improve efficiency and C1 Use targeted conventional speed enforcement programs at locations effectiveness of speed known to have speeding-related crashes (P) enforcement efforts C2 Implement automated speed enforcement (T) C3 Increase penalties for repeat and excessive speeding offenders (T) C4 Strengthen the adjudication of speeding citations to enhance the deterrent effect of fines (T) C5 Increase fines in special areas (T) V-2

OCR for page 19
SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-1 (Continued) Objectives and Strategies for Addressing Speeding-Related Fatalities Objectives Strategies D. Communicate appropriate D1 Improve speed limit signage (T) speeds through use of traffic control devices D2 Implement active speed warning signs (T) D3 Use in-pavement measures to communicate the need to reduce speeds (T) D4 Implement variable message signs (High Speed Only) (T) E. Ensure that roadway design E1 Use combinations of geometric elements to control speeds and traffic control elements (horizontal and vertical curves, cross section), including providing support appropriate and design consistency along an alignment (T) safe speeds E2 Effect safe speed transitions through design elements and on approaches to lower speed areas (T) E3 Provide appropriate intersection design for speed of roadway (T) E4 Provide adequate change + clearance intervals at signalized intersections (P) E5 Operate traffic signals appropriately for intersections and corridors (signal progression) (T) E6 Provide adequate sight distance for expected speeds (P) E7 Implement protected-only signal phasing for left turns at high-speed signalized intersections (High Speed Only) (T) E8 Install lighting at high-speed intersections (High Speed Only) (T) E9 Reduce speeds and/or volumes on both neighborhood and downtown streets with the use of traffic calming and other related countermeasures (Low Speed Only) (T) categorized according to the objectives discussed above, are discussed in detail in this section. The order in which the strategies are listed does not imply a priority with which they should be considered. Most of the strategies are relatively low-cost, short-term treatments for reducing speeding- related fatalities, consistent with the focus of the entire AASHTO Strategic Highway Safety Plan (SHSP). For each of these, a detailed discussion of the attributes, effectiveness, and other key factors describing the strategy is presented below. Several higher-cost, longer- term strategies which have been proven effective in reducing speeding are also presented in this section, but in less detail. While application of these is outside the implementation framework envisioned by the SHSP, their inclusion in this guide serves to complete the picture of proven, tried, and experimental strategies for reducing speeding-related fatalities. In addition, strategies that have been discussed in other guides in this series, such as some of those related to intersection improvements, are discussed in less detail in this guide, and the reader is encouraged to review the other pertinent volumes. V-3