From Pima County (AZ) Department of Transportation
Specific issues and goals for maintaining bikeways and the roadway edge where the majority of bicycling takes place.
Maintenance of roadways and bikeways is important for user safety and for protection of public funds invested in these facilities. Well-maintained facilities lead minimized road hazards and to increased usage of facilities.
Investment of public funds in maintenance of existing roadway and bicycle facilities is as essential as the development of new facilities. Most jurisdictions can readily point to a backlog of maintenance needs indicated by needs assessments performed by transportation agencies, pavement management systems maintained by the agencies, and public surveys and input.
This section discusses bicyclists' needs for well-maintained roadways and bikeways and provides goals for improved maintenance. Maintenance of the on-street bikeway system should be included directly as part of standard roadway maintenance. To the degree feasible, maintenance of bikeways should be further emphasized based upon public requests and on routine inspection for cracks, pavement damage, and accumulated debris.
Roadways and bikeways should be maintained to accommodate all users of the facilities to a reasonable level of safety. As the American Association of State Highway and Transportation Officials (AASHTO) 1991 Guide for the Development of Bicycle Facilities states, "to varying extents, bicycles will be ridden on all highways where they are permitted."
Maintenance of roadways and bikeways for bicycle use is based in part on an understanding of bicyclists' needs, particularly concerning the roadway edge where the majority of bicycling takes place. Ridges and cracks, such as often develop between the roadway pavement and gutter pan, can be hazardous to bicyclists. Existing drainage grates which have longitudinal slots or which are not flush with pavement can trap a bicycle wheel and contribute to accidents.
Common maintenance concerns such as potholes, cracks and debris in the roadway cause problems not only for bicyclists but for motorists as well. Wet leaves, rocks, gravel, sand, snow, ice, branches, and glass present difficulties for bicyclists, often causing bicyclists to use more of the travel lane or even swerve unpredictably in order to avoid these hazards. Responsive and appropriate levels of sweeping and maintenance will facilitate safe and responsible bicycle travel on roadways and bikeways.
Accumulated debris at the roadway edge or in the bicycle lane is one of the most common obstacles to safe use of facilities by bicyclists. A regular inspection and maintenance program is important to prioritize limited sweeping resources, and helps identify other problem conditions including potholes and cracks.
1. Inspect arterials and collectors, once per year.
2. Respond to service requests within a week or sooner if possible to remove potentially hazardous debris.
3. Sweep arterials and collectors (including the bike lane area) once per month, or more frequently as needed based on inspections and service requests.
4. Sweep local roadways four times per year or more frequently based on inspections and service requests.
5. Remove debris from the curb and gutter pan area.
6. Sweep up debris as soon as possible after accidents to a level sufficient to accommodate bicycle travel.
7. Remove sand and cinder materials after the winter season ends or after major storms in high bicycle-use areas.
Maintenance of the roadway and bike lane pavement surface to acceptable standards is important to attract potential bicyclists to use facilities as well as to safely provide for existing users. Enhanced maintenance levels and preventative maintenance practices is desirable to provide rideable surface pavement minimizing bumps, cracks, edges or drop-offs, ridges, and potholes. As mentioned previously, inspection and service response practices for roadway and bikeway sweeping can be combined with those for pavement surface maintenance for improved efficiency.
1. Inspect arterials and collectors once per year for pavement surface problems and to rate pavement condition, or more frequently based on service requests.
2. Repair bikeways for surface problems when identified or requested. Seal pavement cracks including between the asphaltic pavement and gutter pan, and grind down surface bumps and ridges in the pavement which may develop in this area. Cut back on intrusive tree roots and repave or grind pavement to provide a rideable surface.
3. Respond to service requests based upon priority, and repair potentially hazardous conditions within 48 hours.
4. Prevent the edge of a roadway repair or utility cut from running through a bike lane if possible. If repairs are necessary in the bike lane, contractors are required to repave it flush with the existing pavement surface free of bumps or depressions, and to maintain this surface for one year. Provide safe passage for bicyclists through or around barricade areas.
5. Repair pavement edge raveling on uncurbed roadways on a timely basis to help extend the life of the pavement and to maintain a rideable surface area.
6. Sweep project areas of debris after roadway pavement repairs, and remove any large, excess asphalt bumps left behind on the pavement surface.
Pavement overlays improve conditions for motorists and bicyclists by eliminating cracks, bumps, potholes, and ridges in the pavement. Pavement overlays and roadway rehabilitation projects are also good opportunities to provide additional space for bicycling by widening the pavement surface area and/or by restriping the roadway to provide bike lanes or wide curb lanes.
1. Coordinate the overlay schedule for opportunities to provide bike lanes or wide curb lanes as part of overlay projects.
2. Extend the pavement overlay over the entire surface area of the road and shoulder or at least 5 feet to the right of the painted edgeline if a bike lane or paved shoulder bikeway is provided. Ridges or edges should not be left in areas where bicyclists ride.
3. Overlay the pavement flush with the gutter pan to reduce problems for bicyclists with ridges and cracks.
4. Pave gravel driveway and side street approaches from the edge of the roadway to the County right-of-way line to help prevent loose gravel and rocks from being brought up onto the roadway or bike lane area. If the right-of-way line is close to the edge of roadway, coordinate with local property owners to the degree feasible to pave further along driveways from the roadway edge.
5. Sweep the project area and remove excess pavement after completion of the overlay.
6. Bring drainage grates, manholes and utility covers to grade after repairing.
Plantings along the side of the road or bikeway may encroach or cause sight distance problems for motorists or bicyclists at driveways or intersections. Encroachment causes bicyclists to ride further into the travel lane to avoid branches or to swerve unexpectedly. Plants blocking motorists' views may cause them to extend their vehicles further into the travel lane or block a sidewalk, bike lane, or multi-use trail in order to see. This may cause motorists to make unsafe crossings in front of oncoming vehicle, bicycle, and pedestrian traffic.
1. Maintain trees and shrubs along roadways and bikeways to prevent encroachment from branches.
2. Respond to maintenance requests for trimming of branches within 48 hours or sooner if warranted.
3. Trim trees and shrubs to provide adequate sight distances at street intersections.
4. Require property owners to maintain vegetation satisfactorily to County standards, were applicable.
5. Cut back on intrusive tree roots and repave or grind pavement to provide a rideable surface. Utilize appropriate treatments to prevent pavement breakup caused by weeds or other plants growing through the pavement.
Signs, stripes and legends fade over time as they are exposed to the elements and, for stripes and legends, to traffic traveling over their surface. Regular inspection and maintenance is important to support regulatory and advisory functions of signs, to increase the visibility of bikeway facilities, and to reduce liability of responsible agencies.
1. Inspect signs, stripes and legends on bikeways on an annual basis or as part of service requests.
2. Replace defective or missing signs as soon as possible.
3. Repaint bike lane stripes and legends once per year, and in high bicycle-use areas potentially twice per year.
Drainage facilities should be designed and maintained with consideration for bicycle traffic. Over time, drainage grates may shift or separate, longitudinal slots may develop, and grates may not have been brought to grade as part of periodic overlay projects. Also, curbs to divert surface drainage into catch basins may have been constructed in the bike lane or roadway shoulder area, thereby presenting hazards to bicycle traffic.
1. Raise drainage grates flush with pavement.
2. Respond to service requests within 48 hours to modify or replace deficient drainage grates with bicycle-safe grates.
3. Address drainage problems where water puddles at roadside edge and remains for extended periods of time, affecting the ability of bicyclists to ride along the roadway or in the bike lane.
4. Remove existing drainage curbs that encroach into the roadway or bike lane.
Chip sealing can leave rough surfaces for bicycling. Chip seals which cover the roadway surface but only part of the shoulder area can cause difficulties for bicyclists due to a ragged edge or ridge. During chip sealing, small rocks can be kicked up from motor vehicles and can be hazardous to bicyclists as well as can crack vehicle windshields. When possible, other alternatives to chip sealing should be utilized.
1. Cover only the travel lanes with chip seal and do not leave ridges at the bike lane stripe or painted edgeline on roadways with bike lanes or paved shoulders that are in good condition.
2. Use 1/4 inch chip seal material for bike lanes or shoulders which must be chip sealed as part of a roadway chip seal project, and chip seal the entire bike lane or shoulder rather than just a portion of it. The 1/4 inch chip seal may also be utilized on the travel lanes for improved efficiencies of application.
3. Use standard sweepers or vacuum sweepers on the roadway after chip sealing, with particular attention to the bike lane or roadway shoulder where greater amounts of loose chip seal material may accumulate.
4. Bring drainage grates, manholes, and utility covers to near grade after chip sealing.
Raised pavement markers can be hazardous to bicyclists and can be problematic to maintain under traffic and snow removal conditions. The AASHTO 1991 Guide for the Development of Bicycle Facilities states that "Raised pavement markings and raised barriers can cause steering difficulties for bicyclists and should not be used to delineate bicycle lanes." The Manual on Uniform Traffic Control Devices (MUTCD) also states that "Raised markers generally should not supplement right edge lines."
1. Remove existing raised pavement markers on edge line stripes and do not place on new edge line stripes.
2. If absolutely necessary for motorist safety, relocate markers to the motorists' side of the stripe.
3. Utilize pavement markers that are flush with the pavement surface that do not cause steering difficulties for bicyclists.