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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-33 (Continued) Strategy Attributes for Providing an Overpass or Underpass (T) Attribute Description Technical Attributes Crash frequency and severity, by type, are key safety effectiveness measures. Grade- separated crossings can be used by all shared use path users (i.e., bicyclists, pedestrians, in-line skaters, etc). Accident analysis should include all types of trail users. Crash frequency and severity data are needed. Both bicycle and traffic volume data are needed to represent exposure. The impact on traffic operations (i.e., level of service of the crossing) should also be evaluated. A final measure is the percentage of bicyclists (and other shared path users) who use the facility compared to those that cross at street level. Associated Needs Grade-separated crossings must meet ADA requirements. Grade-separated crossings should also be able to accommodate maintenance and emergency vehicles. Organizational and Institutional Attributes Organizational, Agencies should establish a policy that may be used to determine the need for a Institutional and grade-separated crossing. Policy Issues Issues Affecting Finding adequate funds to construct an overpass or an underpass may impact Implementation Time implementation time. Acquisition of additional right of way may be required which could significantly impact the implementation time, and significant time will be required to design the structure. Costs Involved The cost for an overpass or underpass can range from $500,000 to $4 million, depending on the site characteristics and right of way acquisition required (Zegeer et al., 2004). Training and Other None identified. Personnel Needs Legislative Needs None identified. Other Key Attributes None identified. Objective B--Reduce Bicycle Crashes along Roadways Strategy B1: Provide Safe Roadway Facilities for Parallel Travel (T) As discussed in Section III, 35.5 percent of bicyclist crashes with motor vehicles occur when travel directions are parallel. Roadway facilities that better identify appropriate travel areas for all road users and their expected behavior may provide a safer environment for bicyclist travel along parallel paths and help reduce crashes. V-49

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SECTION V--DESCRIPTION OF STRATEGIES Bicycle Lane Striping Striped bicycle lanes provide marked areas for bicyclists to travel along roadways and provide for more predictable movements for both bicyclists and motorists. Striped bike lanes can be incorporated into a roadway when it is desirable to delineate which available road space is for exclusive or preferential use by bicyclists. The AASHTO Bicycle Guide (1999) provides detail for installation of striped bicycle lanes. Bike lanes are usually along the right edge of the roadway but may be placed to the left of parking or right-turn lanes. Marked bicycle lanes on roadways should be one-way only and carry bicycle traffic in the same direction as adjacent motor vehicle traffic. Bike lane markings can reduce the risk of "dooring" (i.e., bicyclists being struck by opening car doors) when the lane runs along a parking lane, although placement of the lane markings is critical for achieving this outcome. Bicycle lanes are often appropriate where most bicyclists on the route are less experienced (Wilkinson et al., 1994). EXHIBIT V-35 Most studies present evidence that bicycle MUTCD Example of Striped Bicycle Lanes lanes may provide protection against (http://mutcd.fhwa.dot.gov/HTM/2003r1/part9/ bicycle/motor vehicle collisions. Evidence fig9c-05_longdesc.htm) also shows that riding with the flow of vehicular traffic reduces bicyclists' chances of collision with a motor vehicle. Locations with bicycle lanes have lower rates of wrong-way riding (Hunter et al., 1998). Most crashes associated with marked bike lanes are concentrated where the marking ends, typically at approaches to intersections, and bicyclists must enter mixed traffic, or at locations where automobiles entering the roadway cross the marked bike lane. Such crashes may be reduced by application of other treatments discussed in this report, including intersection and driveway treatments. Striped bicycle lane design can be quite challenging in situations where the existing urban traffic patterns are complex and cross- sections are already constrained by heavy traffic volumes. Examples of different lane cross sections based on different roadway characteristics are shown in Exhibit V-36. Examples include the following: Oakland, CA--Since 1999, Oakland has installed nearly 93 mi of bicycle lanes. Many of these individual projects are described on their website: http://www.oaklandpw.com/bicycling/ bikelanes.htm. V-50

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-36 Example of Roadway Cross Sections with Bicycle Lanes (AASHTO, 1999) Phoenix, AZ--In 1987, Phoenix began implementing an aggressive program to install over 700 mi of striped bicycle lanes. A net decrease in the rate of bicycle/ motor vehicle crashes has been observed, although the number of bicyclist fatalities has remained constant. A case study describing Phoenix's experience is included in the BikeSafe Countermeasure Selection System (http://www.bicyclinginfo.org/ bikesafe). V-51

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-37 Additional information on bicycle lane Chevron Shared Lane Marking in San Francisco striping may be found at: (Deirdre Weinberg, San Francisco Metropolitan Transportation Agency, 2004) Pedestrian and Bicycle Information Center--http://www.bicyclinginfo. org/de/onstreet.htm#bike Chicago, IL--http://www. bicyclinginfo.org/de/ bikelaneguide.htm (Bike Lane Design Guide) [Note: some of the designs in the Chicago Bike Lane Design Guide are not consistent with current MUTCD standards.] City of San Francisco, CA--http:// sfgov.org/bac/anlreport1001.htm Florida Department of Transportation--http://www11. myflorida.com/safety/ped_bike/ handbooks_and_research/ bhchpt4.pdf EXHIBIT V-38 San Francisco's Standard Shared Lane Marking and Placement (Burk and Shared Lane Marking Sallaberry, 2004) Shared lane markings are a promising experimental method for providing parallel travel facilities. Similar in concept to striped bicycle lanes, shared lane markings consist of markings placed in the area of desired bicyclist travel. The markings do not indicate a separated bicycle lane, but instead direct bicyclists to travel outside the car door zone and improve awareness of bicyclists and motorists that they are sharing part of the roadway environment. Shared lane markings have the advantage over striped bike lanes of also reducing wrong-way riding and car door crashes. They are intended for use primarily on roadways where traffic lanes are too narrow to be safely shared side-by-side by bicyclists and motor vehicles. Example: San Francisco, CA--San Francisco conducted an extensive study of different shared lane markings, and developed recommendations that are now included in California's MUTCD for use on streets where there are parallel on-street functions. More V-52

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SECTION V--DESCRIPTION OF STRATEGIES information about San Francisco's program can be found at: http://www.bicycle.sfgov.org/ site/dptbike_index.asp?id=22747. Information about shared lanes in general, including signed shared lanes, may be found at http://www.bicyclinginfo.org/de/onstreet.htm#signed. Paved Shoulder Paved shoulders are very similar to bike lanes as a bicycle facility. The pavement edge line for the paved shoulder provides separated space for the bicyclist much like a bike lane. The AASHTO Bicycle Guide notes that in rural areas "adding or improving paved shoulders often can be the best way to accommodate bicyclists," and shoulders have the additional attraction of providing a variety of benefits to motorists and other road users as well. Widths are a function of motor vehicle speeds, volume, percentage of truck and bus traffic, etc. If the paved shoulder is less than 1.2 m (4 ft) in width it should not be designated or marked as a bicycle facility. Widths should be increased with higher bicycle volumes, motor vehicle speeds above 80 km/h (50 mph), or higher percentage of truck and bus traffic. Further guidance on the appropriate width of shoulders to accommodate bicyclists on roadways in these situations can be found in FHWA's Selecting Roadway Design Treatments to Accommodate Bicyclists. Paved shoulders tend to result in fewer erratic motor vehicle driver maneuvers, more predictable bicyclist riding behavior, and enhanced comfort levels for both motorists and bicyclists (Harkey et al., 1996). Example: Wisconsin DOT has a policy of providing a 0.9 m (3 ft) paved shoulder on all highways with an average daily traffic in excess of 1,000 vehicles, and this is widened to 1.5 m (5 ft) if a moderate number of bicyclists regularly use the road (Wisconsin DOT, 2003). For more information, see the following resources: Oregon's ped-bike program's discussion of paved highway shoulders: (http://www.odot.state.or.us/techserv/bikewalk/whyhave.htm) http://www.bicyclinginfo.org/de/onstreet.htm (Includes discussion of both paved shoulders and wide outside lanes, as well as a comparison of striped bike lanes to paved or wide shoulders.) Colored Pavement Marking Colored pavements (e.g., green bike lanes) or different paving materials have been used in certain situations to distinguish bike lanes from the motor vehicle lanes. Use of colored bike lanes is being considered but is not yet an accepted MUTCD standard. Colored pavement markings have mostly been applied and studied at intersections and other high-conflict areas where motor vehicles are more likely to enter the bicycle lane. A description of colored bicycle lanes for use at intersections is also included with Strategy A4--Improve Pavement Markings at Intersections in this guide. Colored bicycle lanes have been used to visually narrow the roadway while also maintaining a preferential area for bicyclist usage. Colored pavement may be appropriate where a wide roadway results in high traffic speeds, but certain forms of traffic calming raise concerns about emergency vehicle access. V-53

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-39 Colored Pavement Placement at High-risk Roadway Location Colored bike lanes have been a feature of bicycle infrastructure in the Netherlands (red), Denmark (blue), France (green), and many other countries for many years. In the United Kingdom, both red and green pigments are used to delineate bike lanes and bike boxes. However, in the United States their use has been limited to a few experiments in just a handful of locations. The most extensive trial took place in Portland, Oregon, where a number of critical intersections had blue bike lanes marked through them, and the results were carefully monitored. For more information about colored lanes and the Portland study, visit http://www.trans.ci. portland.or.us/bicycles/bluebike.htm. EXHIBIT V-40 Strategy Attributes for Providing Marked Roadway Facilities (T) Attribute Description Technical Attributes Targets This strategy targets both bicyclists and motorists by providing multiple cues that indicate preferential areas for each to travel along roadways. Expected Marked roadway improvements such as striped bicycle lanes and other treatments Effectiveness suggest a protective effect for certain types of bicycle/motor vehicle collisions (Lott and Lott, 1976). Striped Bike Lane Bike lanes have been found to provide more consistent separation between bicyclists and passing motorists than shared travel lanes. The presence of the bike lane stripe has also been shown from research to result in fewer erratic motor vehicle driver maneuvers, more predictable bicyclist riding behavior, and enhanced comfort levels for both motorists and bicyclists (Harkey et al., 1996). The extra space created for bicyclists is also a benefit for V-54

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-40 (Continued) Strategy Attributes for Providing Marked Roadway Facilities (T) Attribute Description Technical Attributes bicyclists on congested roadways where bicyclists may be able to pass motor vehicles on the right. Shared Lane Markings Shared lane markings have resulted in a 203 mm (8 in) increase in the distance of bicyclists from parked cars. The markings also resulted in an increase of over 0.6 m (2 ft) between bicyclists and passing motorists. Markings also reduce the number of bicyclists who ride on sidewalks, as well as resulting in an 80 percent reduction in wrong-way riding (Burk and Sallaberry, 2004). Wide Curb Lanes Wide curb lanes provide an area sufficiently wide for both motor vehicles and bicyclists to use the lane. Research (Harkey et al., 1996) has shown that paved shoulders tend to result in fewer erratic motor vehicle driver maneuvers, more predictable bicyclist riding behavior, and enhanced comfort levels for both motorists and bicyclists. Colored Pavement Marking Colored pavement markings are expected to increase the visibility of bicyclists by explicitly defining the bicyclist right-of-way. In Portland's painted lane experiment, significantly more motorists yielded to bicyclists and slowed or stopped before entering colored pavement areas. Keys to Success Where bicycle lanes exist, riding should be restricted to the direction of motor vehicle travel. Adequate facility lane width should be provided to accommodate bicyclists. Information through signage and/or pavement marking should be provided to encourage desired behavior and guide users to the facilities. Custom or specially developed signs may be necessary for new facilities. EXHIBIT V-41 Signs Developed for Portland's Colored Lanes (http://www.trans.ci.portland.or.us/bicycles/Bluelane.pdf) V-55

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-40 (Continued) Strategy Attributes for Providing Marked Roadway Facilities (T) Attribute Description Technical Attributes Adequate space between the bike lane and parked cars should be provided so that open doors do not create a hazard for bicyclists. Termination of bike lanes that place bicyclists in a vulnerable situation should be avoided. Finally, it is important to determine if special signs or markings are necessary for situations such as a high-volume of bike left turns on a busy roadway. Potential Difficulties Although treatments included here have been studied and shown favorable results, not all are currently included in the MUTCD. The MUTCD is regularly revised, and most of these treatments are under consideration. The level of a bicyclist's experience influences facility preferences. There is rarely one pavement treatment that satisfies all users. Wide curb lanes are not generally as effective as striped bike lanes and marked shared lanes at reducing wrong-way riding. The cost of maintaining stripes, shared lane markings, and colored bicycle lanes may be high, but proper selection of paint or colored surface material can minimize these costs. Proper placement of on-road bicycle facilities requires balancing user needs with right-of-way limitations. Placement of bicycle lanes on roads with parallel parking, in particular, should occur so that impacts with car doors are unlikely; this is accomplished by placing the lane markings outside the expected door opening area. There may be resistance to establishing bicycle lanes from a portion of the community. This resistance may be based on perceptions of erratic bicyclist behavior, and might be overcome with an effective PI&E program. Appropriate Measures Comparing before and after data about bicyclist exposure or usage and crash or injury and Data data would provide the most comprehensive evaluation of roadway facilities for bicyclists. However, useful exposure data is usually unavailable, leaving only crash or injury data for evaluation. Associated Needs Although many bicyclists and motor vehicle operators understand how to ride or drive on roads with striped bicycle lanes, installation of other on-road bicycle facilities should be accompanied by public information campaigns to clarify how they should behave with the new facilities. Organizational and Institutional Attributes Organizational, The needs of bicyclists and motorists must be balanced when considering any Institutional, and changes to roadways. Factors such as lane widths, operating space, parking, Policy Issues vehicle speeds, etc. need to be completely examined so that the most appropriate alternative can be selected. Issues Affecting Facilities that consist of adding paint to the roadway can be implemented within a very Implementation Time short timeframe. Paved shoulders require significantly more time to plan and construct. V-56

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-40 (Continued) Strategy Attributes for Providing Marked Roadway Facilities (T) Attribute Description Organizational and Institutional Attributes Costs Involved The BikeCost tool (http://www.bicyclinginfo.org/bikecost) provides an online estimation calculator of approximate cost for many bicycle facilities, including marked roadway facilities. The cost of installing a bicycle lane is approximately $3,100 to $31,000 per kilometer ($5,000 to $50,000 per mile), depending on the condition of the pavement, the need to remove and repaint the lane lines, the need to adjust signalization, and other factors. It is most cost efficient to create bike lanes during street reconstruction, street resurfacing, or at the time of original construction. Shared lane markings have significantly lower initial and maintenance costs compared to striped bicycle lanes. Paved shoulder costs can be quite variable. Using data from Iowa DOT average contract prices for calendar year 2000, a minimum design width of 1.2 m (4 ft) of paved shoulder width to accommodate bicycle traffic was estimated at $44,000 per kilometer ($71,000 per mile) (Souleyrette et al., 2001). Painted bicycle lanes cost approximately $3,700 per kilometer ($6,000 per mile) in both directions. The cost of widening and resurfacing a section of roadway to make painting appropriate varies depending on current conditions, but a minimum cost estimate is at least $93,200 per kilometer ($150,000 per mile). Training and Other None identified. Personnel Needs Legislative Needs The use of any treatment that is not contained in the MUTCD requires the approval of the FHWA. Other Key Attributes Wide Curb Lane Wide curb lanes are an alternative to marked roadway facilities such as bicycle lanes Alternative and shared lane markings. They are intended to create on-street facilities for bicyclists by creating a lane that is wide enough so motor vehicles and bicycles have adequate room to share the lane during overtaking. Advocates of wide curb lanes believe that they encourage bicyclists to operate more like motor vehicles and thus lead to more correct positioning at intersections, particularly for left-turn maneuvers. A wide curb lane is the lane nearest the curb that is wider than a standard lane and provides extra space so that the lane may be shared by motor vehicles and bicyclists. Wide curb lanes can be placed on roads with or without curbs. Wide curb lanes may be present on two-lane or multi-lane roads. The desired width is 4.3 m (14 ft) for the lane, not including the gutter plan area. Wider lanes may result in the operation of two motor vehicles side-by-side in the lane, and narrower widths may not provide adequate space for the bicyclist and motor vehicle to operate side-by-side. In addition, the usable lane width is reduced by drainage grates, raised reflectors, or on-street parking, so lane width should be increased to accommodate those impediments. Because wide curb lanes are a shared-lane countermeasure, they are not marked or signed like a bicycle lane. As a result, bicyclists may not know of their existence or utility as a bicycle facility. V-57

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-40 (Continued) Strategy Attributes for Providing Marked Roadway Facilities (T) Attribute Description Other Key Attributes Shared lane markings may supplement wide curb lanes. These markings would provide a relatively low-cost approach to help identify the facility for bicyclists. Shared lane markings may also encourage proper placement of the bicyclist within the wide curb lane and will encourage bicyclists to travel in the same direction as motor vehicle traffic. Width of Bicycle Minimum and maximum design widths for bicycle lanes should be carefully examined. Lanes For example, bicycle lane widths of 1.8 m (6 ft) maximum may be desirable when one or a combination of the following conditions exists: traffic volumes and speeds are high; adjacent parking use and turnover is high; catch basin grates, gutter joints, and other features in the bicycle lane may present an obstacle to cyclists; steep grades exist; truck volumes are high; or bicycle volumes are high. Also, bicycle lane widths of 1.2 m (4 ft) minimum may be acceptable when: physical constraints exist for a segment of less than 1.6 km (1 mi) that links to existing bikeways on both ends, implemented in conjunction with traffic calming devices (see Strategy C1-- Implement Traffic Calming Techniques), adjacent to parking with [very] low use and turnover, or adjacent to an uncurbed street shoulder. Strategy B2: Provide Contraflow Bicycle Lanes (T) Contraflow Bicycle Lanes A contraflow bicycle lane establishes a two-way street for bicyclists on a street that only allows one-way motor vehicle traffic. Contraflow lanes allow bicyclists to travel in the opposite direction from motor vehicle traffic on the same roadway. Bicyclists are generally expected to follow established rules-of-the-road such as riding in the same direction as motor vehicle traffic. However, there are certain situations where the placement of a bicycle lane counter to the normal flow of traffic can increase safety or improve access for bicyclists. Some one-way streets, particularly in hilly or downtown areas, may provide benefits to bicyclists if a contraflow bike lane is designated to allow bicyclists to ride against the flow of traffic. V-58

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SECTION V--DESCRIPTION OF STRATEGIES It should be made clear that there are EXHIBIT V-42 safety concerns associated with Contraflow lane application in Cambridge, MA (Photo by Cara Seiderman) wrong-way riding, as this places bicycles in a position where motorists do not expect to see them. However, there is precedent for opposite direction riding that emanates from Europe, where bicyclists are often allowed to ride in the opposite direction on one-way streets, usually with slow motor vehicle traffic. The contraflow bike lane is a specific bicycle facility that can be used in special situations and is intended to reduce the number of conflicts between bicycles and motor vehicles. The facility also would be intended to save time for bicyclists having to travel an extra distance if they rode with traffic. It may also alleviate riding on a high speed, high volume route. Examples of contraflow bike lanes can be found in cities in the United States with large numbers of bicyclists, including Cambridge, Massachusetts; Boulder, Colorado; Madison, Wisconsin; and Eugene, Oregon. The Madison contraflow lane--University Avenue--runs through the heart of the University of Wisconsin campus and carries heavy flows of bicyclists and other road users. Because of the high demand for bicycle travel in both directions, the road was rebuilt with a bus lane, bike lane, and three travel lanes in one direction and a bike lane only (separated by a raised median) in the other direction. EXHIBIT V-43 For more information about contraflow Contraflow Lanes may Require Specific Signs bicycle lanes: (BikeSafe--www.bicyclinginfo.org/bikesafe) BikeSafe Countermeasure Selection System includes a number of case studies of contraflow lanes: (http:// www.bicyclinginfo.org/bikesafe) Portland, Oregon's Bicycle Design and Engineering Guidelines (http://www. trans.ci.portland.or.us/designreferences/ bicycle/appenda3.htm) San Francisco Bay Area Metropolitan Transportation Commission's Bicycle and Pedestrian Safety Toolbox (http://www. bayareatrafficsignals.org/toolbox/Tools/ ContraFlowBike.html) V-59

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-44 (Continued) Strategy Attributes for Providing Contraflow Bicycle Lanes (T) Attribute Description Organizational and Institutional Attributes Costs Involved The cost of installing bike lane markings (such as for contraflow lanes) is approximately $3,100 to $31,000 per kilometer ($5,000 to $50,000 per mile), depending on the condition of the pavement, the need to remove and repaint the lane lines, the need to adjust signalization, and other factors. It is most cost efficient to create bike lanes during street reconstruction, street resurfacing, or at the time of original construction. Training and Other None identified. Personnel Needs Legislative Needs None identified. Other Key Attributes Potential Use Sidewalks should not be used as bicycle facilities. Some early bikeways used sidewalks of Sidewalks for both pedestrians and bicyclists. While in rare instances this type of facility may be necessary, or desirable for use by small children, in most cases it should be avoided. In instances where it cannot be avoided, carefully considered and prepared education for the children should be a component of the use (http://www.odot.state.or.us/techserv/ bikewalk/planimag/II1c.htm). Sidewalks are not suited for bicycling for several reasons: Bicyclists face conflicts with pedestrians. There may be conflicts with utility poles, sign posts, benches, etc. Bicyclists face conflicts at driveways, alleys, and intersections: a bicyclist on a sidewalk emerges onto driveways and alleys unexpectedly and is generally not visible to motorists. This is especially true of bicyclists who ride opposing adjacent motor vehicle traffic; drivers do not expect a vehicle coming from this direction. Bicyclists are put into awkward situations at intersections where they cannot safely act like a vehicle but are not in the pedestrian flow either, which creates confusion for other road users. Where constraints do not allow full-width bikeways, solutions should be sought to accommodate both modes (e.g. narrowing travel lanes or reducing on-street parking). In some urban situations, preference may be given to accommodating pedestrians. Sidewalks should not be signed for bicycle use--the choice should be left to the users. Strategy B3: Improve Bicyclists' Visibility (T) Lighting Improved roadway lighting may help to reduce crashes that occur under less than optimal light conditions. Intersections may warrant higher lighting levels than roadway segments. Good lighting on roadways, bridges, tunnels, and multi-use paths is also important for personal security. Sufficient roadway illumination also helps nighttime bicyclists see surface conditions and obstacles or people in the path of travel. V-62

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SECTION V--DESCRIPTION OF STRATEGIES Bicyclists, particularly commuters, may have to ride during early dawn hours or during twilight or darkness, particularly in the winter months. Although bicyclists riding during dark conditions are generally required to have appropriate lighting on their vehicles or persons, requirements vary from state to state, and bicyclists can still be vulnerable to not being seen by motor vehicle operators. Conspicuity, making the bicyclist more conspicuous with lights and retroreflective material, is a behavioral treatment that is discussed in Strategy F2. Lighting is a complex treatment requiring thoughtful analysis. Not only are there safety and security issues for bicyclists, pedestrians, and motorists, but potential light pollution, long- term energy costs, and aesthetics also become factors. With good design, lighting can enhance safety of the bicycling as well as pedestrian environment and improve the ambience of areas of nighttime activity. Virtually all research on lighting has focused on motor vehicles, with much of that research related to highways. More research is needed on the safety and mobility benefits of lighting improvements to bicyclists. Examples include the following: For more information about improving lighting conditions for bicyclists, the Wisconsin Bicycle Facility Design Handbook provides guidance for path illumination (p. 435 to 437 available from: http://www.dot.wisconsin.gov/projects/state/docs/bike-facility.pdf). For in-depth roadway lighting specifications, see American National Standard Practice for Roadway Lighting ANSI IESNA RP-8 (available from the Illuminating Engineering Society). The Florida Department of Transportation provides some guidance on the lighting of bicycle facilities at: http://www.dot.state.fl.us/safety/ped_bike/handbooks_and_research/bhchpt4.pdf. EXHIBIT V-45 Strategy Attributes for Improving Bicyclists' Visibility (T) Attribute Description Technical Attributes Targets Improved lighting targets both bicyclists and motor vehicle drivers. Better lighting allows bicyclists to see the roadway and debris or potential obstructions. It also makes bicyclists more visible to drivers in low light conditions. Expected Improved lighting is expected to change conditions to reduce bicycle/motor vehicle Effectiveness crashes. Optimize visibility of bicyclists (and pedestrians) during low-light conditions, particularly in locations where high numbers of bicyclists may be expected such as commuter routes, routes to and from universities, intersections, and intersections with multi-use trails. Improve personal security of bicyclists and make roadway safer for all users. Data from 5 years of North Carolina bicycle/motor vehicle crashes indicate that about one-quarter of reported collisions and more than one-half of bicyclist fatalities occurred during non-daylight conditions, probably far exceeding the proportion of riding that occurs under these conditions (http://www.pedbikeinfo.org/pbcat/bike_main.htm). V-63

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-45 (Continued) Strategy Attributes for Improving Bicyclists' Visibility (T) Attribute Description Technical Attributes Similarly, estimates from Florida State University (http://www.safety.fsu.edu/ bicyclemanual.html#accidents ) indicate that "nearly 60 percent of all adult fatal bicycle accidents in Florida occur during twilight and night hours even though less than 3 percent of bicycle riding takes place during that time period." Keys to Success The AASHTO Bicycle Guide recommends using average maintained illumination levels of between 5 and 22 lux. Additional research is needed on the safety and mobility benefits of lighting improvements to bicyclists. Potential Difficulties Lighting decisions should include consideration of potential light pollution, long-term energy costs, and aesthetics. With good design, lighting can enhance safety of the bicycling as well as pedestrian environment and improve the ambience of areas of nighttime activity. Other difficulties may include acquiring adequate funding to install new lighting with new construction projects. Appropriate Measures In addition to standard measures of crash frequency and severity, a key measure is and Data whether the new installations bring lighting levels up to recommended levels. Associated Needs Install lighting on both sides of wide roadways for most effective illumination. Provide generally uniform illumination avoiding hot spots, glare, and deep shadows; some intersections may warrant additional illumination. Consider rural locations for lighting improvements if nighttime or twilight crashes are a problem. Organizational and Institutional Attributes Organizational, It is important for state and local agencies to establish policies for lighting of bicycle Institutional, and facilities, as well as a procedure for identifying and implementing needed lighting Policy Issues improvements. Most state DOTs have policies that limit or prohibit payment for lighting as part of road construction projects, leaving funding for lighting as a local contribution. Issues Affecting This strategy does not require a long development process. Lighting improvements can Implementation Time typically be implemented in less than 6 months. Availability of funding for lighting improvements is a key issue affecting implementation time. Also, local governments often prefer more expensive, decorative lighting instead of the standard lighting recommended by many state standards. Resolving these issues, including who pays for various aspects of the improvements, can delay lighting project completion. Costs Involved Cost varies depending on fixture type, design, local conditions, and utility agreements. Training and Other Lighting improvements can be made by agency personnel or by private contract. Personnel Needs In both instances, experienced personnel are needed to design and install lighting improvements. Monitoring and maintenance programs are also needed, including night inspections. V-64

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-45 (Continued) Strategy Attributes for Improving Bicyclists' Visibility (T) Attribute Description Organizational and Institutional Attributes Legislative Needs Local legislative bodies (city and county governing boards) may establish policies that require adequate lighting for bicyclists and pedestrians in all new developments. This may reduce the direct governmental costs incurred to install adequate lighting. Other Key Attributes Behavior Another lighting issue to consider is the use of lights and reflectors by bicyclists. This topic is discussed in Strategy F2-Increase Rider and Bicycle Conspicuity. Generally, when riding at night, bicyclists are required to have front and rear lights (or rear reflectors)-both to aid in their detection and to help them see what's in front of them. The Oregon DOT has an easy-to-understand section of its manual that addresses the equipment needs of bicyclists, including lights (http://www.odot.state.or.us/ techserv/bikewalk/planimag/bicycle.htm#equipment). Lighting Option The type of lighting (mercury vapor, incandescent, or high pressure sodium) should be selected based on the needs for a given roadway. Strategy B4: Improve Roadway Signage (T) Signs are placed along roadways to provide regulation, warning, and guidance information to road users, including bicyclists. This strategy focuses on providing additional regulatory and directional signs to improve bicycle safety and behavior along roadways. The AASHTO Bicycle Guide (1999) and MUTCD (2003) should be consulted concerning bicycle-related signs. Shared Roadway Signage EXHIBIT V-46 Share the Road Sign The intent of shared roadway signage is to let bicyclists and (USDOT, 2003) motorists know what to expect along the roadway, thus improving the chances that they will react and behave appropriately. These signs reinforce that bicyclists have a legal right to use the roadway. The safety effectiveness of shared roadway signs has not been evaluated, and their overall use is thought to be decreasing. Some experts now feel that they are only appropriate in "pinch point" locations where roadway facilities may not fully accommodate both bicyclists and motorists. Shared roadway signs typically consist of yellow warning signs with the legend "Share the Road" and a bicycle and car logo (Exhibit V-46). Similar messages may be used, including "Cars Share the Road," to specifically indicate that motor vehicles V-65

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-47 should accommodate bicyclists in the Special Bicycle Signs may be Needed roadway. These signs are typically placed for Unusual Circumstances (MUTCD) (http://mutcd.fhwa.dot.gov/HTM/2003/part9/ along roads with significant bicycle traffic fig9b-02_longdesc.htm) but relatively hazardous conditions for riding, such as narrow travel lanes with no shoulder, roads or streets with poor sight distance, or a bridge crossing with no accommodation for bicycles. Special Bicycle-Related Signage As with shared roadway signage, special bicycle-related signage conveys important information intended to provide information to bicyclists and motorists so they know what to expect, and thus improve the chances that they will react and behave appropriately. Examples of special bicycle-related signs include the use of "No Parking in Bike Lane" signs, intended to keep bike lane spaces clear for cyclists, "Bikes Wrong Way" signs, special warnings to alert motorists and bicyclists about specific approaching conditions that might present a dangerous environment, and specific regulatory signs. Regulatory signs, such as "Stop," "Yield," or turn restrictions require driver actions and are enforceable. "No Turn on Red" signs can improve safety for bicyclists (and pedestrians). Problems often occur at RTOR locations as motorists look to the left for a gap in traffic, especially if bicyclists are riding the wrong way either in the street or on the sidewalk. Care should always be exercised when placing non-standard signs. Proliferation of special bicycle-related signs may limit their impact as well as decrease the effectiveness of other signs. For more information about special bicycle-related signage, the Pedestrian and Bicycle Information Center's bicycle signs and markings information page contains links and examples of most established sign types: http://www.bicyclinginfo.org/de/signs_markings.htm. The MUTCD (2003) defines national standards for signs relating to bicyclists along roadways (http://mutcd.fhwa.dot.gov/HTM/2003r1/part9/part9-toc.htm). Bicycle Route Signage By providing bicycle route signs that identify official bicycle routes and provide additional information about the route, bicyclist travel can be directed to areas that have better facilities, as well as provide both bicyclists and motorists additional information about their expected behavior. Typical bicycle route signage identifies that a roadway is part of a bicycle route and then identifies the primary destination served by the route. Bicycle routes can consist of local routes, as well as regional routes. They often are used where a local community has identified a system of preferred bicycle routes. V-66

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-48 MUTCD Standard Bicycle Route Signs (http://mutcd.fhwa.dot.gov/HTM/2003r1/part9/fig9b-04_longdesc.htm) Placement of bicycle route signs is important for achieving successful compliance with the bicycle routes, as well as providing a more welcoming environment for bicyclists. They also increase motor vehicle operator expectations of encountering bicyclists along the route, which increases the potential that a motorist will detect, recognize, and avoid potential collisions with a bicyclist. EXHIBIT V-49 MUTCD Recommended Placement of Bicycle Route Signs (http://mutcd.fhwa.dot.gov/HTM/2003r1/part9/fig9b-06_longdesc.htm) V-67

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SECTION V--DESCRIPTION OF STRATEGIES Creating bicycle routes is an inexpensive but visible way to improve the bicycling environment by taking advantage of the existing bicycle facility network. Although evaluation of the existing environment and careful planning should be conducted before establishing bicycle routes, the bicycle routes and signs can be changed with relative ease. This is important when experimenting with route ideas and approaches. Unlike moving a poorly sited bicycle bridge, for instance, it is relatively easy to remove signs and then install them in a different location. Bicycle route systems may function as a means of identifying potential sites for other types of improvements in order to complete a functional network. For instance, building a bike bridge at a particular location can help complete a route through one part of town; striping bike lanes can help make it work in another. EXHIBIT V-50 Strategy Attributes for Improving Roadway Signage (T) Attribute Description Technical Attributes Targets Bicycle-related signs are primarily targeted towards providing information and affecting the behavior of bicyclists, although motorists may also benefit from having access to the information contained in the signs. Some signs, particularly "Cars Share the Road" signs, are targeted specifically at motor vehicle operators. Expected Roadway bicycle-related signs are effective at communicating information and Effectiveness regulations about how both bicyclists and motorists should operate in the roadway. They are important for safety improvement, helping bicyclists avoid unsafe conditions or navigate unfamiliar locations. Keys to Success Success of many roadway signs for bicyclists is dependent upon proper installation and designation at intersections, where bicyclists and motorists first encounter the roadway facility, or in other locations where roadway conditions change. Information about signage at intersections is found in Strategy A3--Improve Signing of this guide. FHWA has an extensive web site about the MUTCD that includes answers to many commonly asked questions about the manual, including one that confirms its status as the national standard for traffic control: "all traffic control devices nationwide must conform to the MUTCD. There are no exceptions" (http://mutcd.fhwa.dot.gov). In addition to the MUTCD, many States supplement the national manual with additional optional signs and markings, or complete Uniform Traffic Control Devices manuals. As an example, the Oregon DOT has a chapter in its bicycle plan detailing which signs and markings should be used in conjunction with bicycle facilities (www.odot.state.or.us/techserv/bikewalk/planimag/II8a.htm). Roadway signs that serve both bicyclists and motorists should be placed and mounted in accordance with standard MUTCD guidance for sign placement, available at http://mutcd.fhwa.dot.gov/HTM/2003r1/part2/part2-toc.htm. V-68

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-50 (Continued) Strategy Attributes for Improving Roadway Signage (T) Attribute Description Technical Attributes EXHIBIT V-51 MUTCD Guidance for General Placement of Signs (http://mutcd.fhwa.dot.gov/HTM/2003r1/part2/fig2a-01_longdesc.htm) Potential Difficulties Care should be taken not to overuse traffic signs. If used in excess, regulatory and warning signs tend to lose their effectiveness. The ease of signing for bicycle routes can also mean that bicyclists may not view the effort as a major commitment to bicycling. Appropriate Measures A key process measure is the number and interval of roadway signs. and Data Crash frequency and severity, by type, are key safety effectiveness measures. Associated Needs None identified. Organizational and Institutional Attributes Organizational, Roadway signs for bicyclists should comply with community policy and desires. Institutional, and Agencies should ensure that bicycle-related signs reflect the community's established Policy Issues or planned bicycle facilities. Issues Affecting This strategy does not require a long development process. Signing improvements can Implementation Time typically be implemented in 3 months or less. Costs Involved Costs to implement signing are relatively low. An agency's maintenance costs may increase. Training and Other Training regarding use of this strategy should be provided in courses covering the Personnel Needs MUTCD and the use of traffic control devices. Legislative Needs None identified. Other Key Attributes None identified. V-69

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SECTION V--DESCRIPTION OF STRATEGIES Strategy B5: Provide Bicycle-Tolerable Shoulder Rumble Strips (T) General Description Bicycle-tolerable shoulder rumble strips are rumble strip configurations that decrease the level of vibration experienced by bicyclists when traversing rumble strips, while at the same time providing an adequate amount of stimuli to alert inattentive/drowsy motorists. Highway shoulder rumble strips have proven to be an effective measure in reducing run-off- the-road (ROR) crashes on urban and rural freeways. (See Strategy 15.1 A1--Shoulder Rumble Strips in NCHRP Report 500, Volume 6: Guide for Addressing Run-Off-Road Collisions and Strategy 15.2 A4--Install Shoulder Rumble Strips in NCHRP Report 500, Volume 7: Guide for Reducing Collisions on Horizontal Curves.) ROR crashes may be reduced by as much as 20 percent to 50 percent when rumble strips are installed. As the use and benefits of shoulder rumble strips are extended to non-freeway facilities, bicyclists will encounter rumble strips more frequently. Bicyclists are concerned about maneuverability problems while traversing rumble strips because they can be very uncomfortable to ride over and may cause loss of control of the bicycle. The incompatibilities between shoulder rumble strips and bicycle use are a major concern and much research has been performed on this issue. The three most comprehensive studies on the effects rumble strips have on bicyclists were conducted in Pennsylvania, California, and Colorado by Elefteriadou et al. (2000), Bucko and Khorashadi (2001), and Outcalt (2001), respectively. Each study included bicycle and motor vehicle testing of various rumble strip designs. In general, the rumble strips that provided the greatest amount of stimuli (i.e., noise and vibration) to alert an inattentive or drowsy driver were also the most uncomfortable for the bicyclists to traverse. Likewise, the rumble strips that were the most comfortable for the bicyclists generated the least amount of stimuli in a motor vehicle to alert an inattentive or drowsy driver. In all three studies, compromises were made when selecting the rumble strip design most compatible for both types of road users. Exhibit V-52 provides the recommended configurations from the respective studies as the most compatible for both motorists and bicyclists. None of these bicycle-tolerable rumble strip configurations should necessarily be considered "comfortable" for a bicyclist to ride over for a considerable length of time. Rather, these rumble strip patterns cause less discomfort and allow for better control of the bicycle when encountered as compared to other rumble strip patterns designed strictly with the motorist in mind. Placement of rumble strips within the right of way is also important for the safety of bicyclists. If placed improperly, rumble strips can render a shoulder unusable for bicycling. The AASHTO Bicycle Guide recommends that rumble strips not be used on routes used by bicyclists unless a minimum of 1.2 m (4 ft) of rideable surface remains for the bicyclist (1.5 m [5 ft] from a curb or guardrail). Other rumble strip policies that have been instituted in an effort to balance the needs of motorists and bicyclists include: Using rumble strips exclusively on limited access or controlled access facilities Using a textured white fog line (Oregon) rather than rumble strips V-70

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-52 Bicycle-Tolerable Rumble Strip Dimensions Groove Width (Parallel to State traveled way) Groove Depth Groove Spacing Comments 127 mm 10 mm 178 mm between Non-freeway facilities with grooves operating speeds near Pennsylvania 88 km/h. (Elefteriadou et at., 2000) 127 mm 10 mm 152 mm between Non-freeway facilities with grooves operating speeds near 72 km/h. 50 mm 25 mm 200 mm on centers None California 125 mm 8 1.5 mm 300 mm on centers None (Bucko and Khorashadi, 2001) Allows for installation of raised/inverted profile thermoplastic in areas where shoulders are less than 1.5 m Colorado 127 mm 10 3 mm 305 mm on centers Recommend gap pattern of (Outcalt, 2001) 14.6 m of rumble strip followed by 3.6 m of gap. Leaving gaps between the rumble strips to allow bicyclists to cross them if necessary (e.g., 3.7 m [12 ft] gaps every 12.2 or 18.3 m [40 or 60 ft]) (Moeur, 2000) Research is underway in National Cooperative Highway Research Program (NCHRP) Project 17-32 to develop further guidance for the design and application of shoulder and centerline rumble strips as an effective motor vehicle crash reduction measure, while minimizing adverse operational effects for motorcyclists, bicyclists, and nearby residents. This research will provide additional guidance related to the installation of rumble strips while taking into consideration the concerns of bicyclists. Additional information on rumble strips can be found at FHWA's resource site about rumble strips at http://safety.fhwa.dot.gov/fourthlevel/pro_res_rumble.library.htm. It should be noted that this strategy focuses on the impact of bicycle-tolerable rumble strips on bicycle safety. The primary purpose of rumble strips, however, is to improve motorist safety. The reader should refer to Strategy 15.1 A1--Shoulder Rumble Strips in NCHRP Report 500, Volume 6: Guide for Addressing Run-Off-Road Collisions and Strategy 15.2 A4--Install Shoulder Rumble Strips in NCHRP Report 500, Volume 7: Guide for Reducing Collisions on Horizontal Curves for more detailed information related to rumble strips and their impact on vehicular safety. V-71

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SECTION V--DESCRIPTION OF STRATEGIES EXHIBIT V-53 Strategy Attributes for Bicycle-tolerable Rumble Strips (T) Attribute Description Technical Attributes Targets Bicycle-tolerable rumble strips are intended to provide a safer environment for bicyclists when rumble strips are present along a roadway. They are not intended to change the behavior of bicyclists. Expected Bicycle-tolerable rumble strip patterns have been recommended to accomplish the Effectiveness intended goal of providing rumble strips to benefit motorists without generating excessive vibration for bicyclists who ride over the rumble strips. The actual safety effectiveness of this treatment is difficult to assess because most agencies do not have data on bicycle-only crashes or loss-of-control bicycle injuries related to rumble strip encounters. However, by installing bicycle-tolerable rumble strips (which have been intentionally designed with the bicyclist in mind) rather than rumble strip patterns that have been designed strictly based upon motorists' needs, it can be expected that bicyclists will experience less vibration when they encounter the bicycle-tolerable rumble strips, resulting in less discomfort and more control over their bicycles, reducing the risk to bicyclists. If bicyclists know that bicycle-tolerable rumble strips are installed along a route, the bicyclists may be more willing to ride along the shoulder, rather than in the travel lane, thus reducing the exposure to motor vehicle traffic. Keys to Success Rumble strip policies that take bicyclists into consideration should be adopted. Shoulder width requirements for installation of rumble strips are very much related to bicycle use. An FHWA Technical Advisory (2001) recommends a minimum shoulder width of 1.8 m (6 ft) where rumble strips are to be installed, but it should also be noted that some agencies require as little as 1.2 m (4 ft) of paved shoulder before rumble strips will be installed. The FHWA Technical Advisory also indicates that a minimum of 1.2 m (4 ft) of shoulder width be given outside of the rumble strips where bicyclists are present. This recommendation is consistent with AASHTO (1999) policy which states that rumble strips are not recommended where shoulders are used by bicyclists unless there is (a) a minimum clear path of 0.3 m (1 ft) from the rumble strip to the traveled way, (b) 1.2 m (4 ft) from the rumble strip to the outside edge of paved shoulder, or (c) 1.5 m (5 ft) to adjacent guardrail, curb, or other obstacle. Exhibit V-52 provides information on groove width, depth, and spacing of bicycle- tolerable rumble strips. Two other dimensions associated with rumble strips that are critical to their impact on bicyclists are the transverse width (i.e., perpendicular to the traveled way) of the rumble strip and the distance the rumble strips are offset from the edge line. Most state policies specify the transverse width to be between 305 and 406 mm (12 and 16 in) (Elefteriadou et al., 2000), and most state policies specify that the rumble strips be offset from the edge line by 152 to 305 mm (6 to 12 in). These two dimensions affect the clear path available for bicyclists. Potential Difficulties Some bicycle groups may be totally against adopting a bicycle-tolerable rumble strip pattern, citing that all rumble strip patterns cause some discomfort and increase the risk for loss of control of bicycles. Rather than adopting a bicycle-tolerable rumble strip pattern, these bicycle groups may take the position that no rumble strips should be installed along routes where bicyclists may be expected to ride. Appropriate Measures Appropriate process measures may include the number of shoulder miles or lane miles and Data where bicycle-tolerable rumble strips are installed. This could be compared to the number of shoulder miles or lane miles of rumble strip installations with dimensions other than those specified to be bicycle-tolerable. V-72