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5.1.2.2 Differential Coloured Surfacing. 5.1.2.3 Road Markings to Diagram 1057. 5.1.4 Adjacent Parking and Loading. 5.1.5 Contra-flow Cycle Lanes. |
Table 5.1: Features of mandatory and advisory cycle lanes.
Table 5.3: Clearance strips between parking and offside cycle lane.
Table 5.4: Kerb-segregated cycle lane widths.
Table 5.5: With-flow bus lane widths.
List of Figures
Figure 5.1: Typical layout of with-flow mandatory cycle lane.
Figure 5.2: With-flow cycle lane adjacent to parking/ loading area.
Figure 5.3: Example of contra-flow cycle lane arrangement
Figure 5.4: With-flow kerb-segregated cycle lane.
Figure 5.5: Bus layby with continuous cycle lane.
Figure 5.6: Cycle lane to rear of bus stop.
Figure 5.7: Cycle lane at bus stop boarding kerb.
Allocating specific carriageway space for cyclists is appropriate where carriageway conditions suit and where cyclists will be advantaged by a degree of separation from vehicular traffic.
Allocating carriageway space involves the marking out of the carriageway width specifically for cyclists, or to share with other specific vehicle types. Facilities include:
The purpose of cycle lanes is to allocate and demarcate space for cyclists within a carriageway in order to:
By reducing the apparent width available to general traffic, cycle lanes may, in conjunction with other measures, be used to support traffic speed reduction.
For cycle lanes to be successful it is necessary that their position on the carriageway is where cyclists want and need to be. Consideration should be given to all cyclists’ movements and whether the overall benefits of providing a cycle lane outweigh the disbenefits.
There are two basic types of cycle lane – mandatory and advisory. Table 5.1 summarises the features of each.
The purpose of a mandatory cycle lane is to define an area of the carriageway that is reserved for cyclists and which other vehicles must not encroach upon.
Advisory cycle lanes are primarily used to warn motor vehicle drivers of the presence of cyclists and to encourage them to adopt a line of travel away from cyclists. It is permissible for vehicles to drive or stop within an advisory cycle lane.
Where space permits and parking and loading can be prohibited effectively, mandatory cycle lanes should be used. Advisory cycle lanes should be considered where occasional vehicle encroachment is unavoidable.
Table 5.1: Features of mandatory and advisory cycle lanes
Mandatory lanes |
Features |
Notes |
|---|---|---|
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Advisory lanes |
Features |
Notes |
|---|---|---|
Used to show indicative area for cyclists. Other traffic can legally enter the cycle lane |
No TRO or mandatory consultation required |
|
Can be used adjacent to parking bays, as a central lane and across junctions |
No powers to enforce against moving vehicle encroachment (except with complementary parking, waiting and loading restrictions) |
|
Can be introduced quickly |
Less signing clutter than mandatory lanes |
A typical mandatory cycle lane layout is illustrated in Figure 5.1.
Figure 5.1: Typical layout of with-flow mandatory cycle lane
The signing arrangement shown in Figure 5.1 is indicative only, and consideration should be given to the problem of sign clutter and the usefulness of using all the signs shown. Applications must be made to Scottish Ministers for any arrangement that does not comply with the TSRGD.
The general layout for advisory lanes is similar to that specified for mandatory lanes (refer to Figure 5.1), however, advisory lanes should be marked with white broken hazard lines (Diagram No 1004 instead of Diagram No 1049) and repeat upright signs to Diagram No 967 instead of Diagram No 959.1.
5.1.2.2 Differential Coloured Surfacing
Differential coloured surfacing, typically green or red, is particularly effective across side road junctions, adjacent to parking and loading bays and queuing traffic. It may be applied over the entire length of a cycle lane, intermittently or just at junctions. Reference should be made to TA81/99 for further detail.
5.1.2.3 Road Markings to Diagram 1057
Cycle symbol markings (TSRGD Diagram No 1057) may be used at the start of both mandatory and advisory lanes and repeated at intervals along its length provided the appropriate upright signing is also in place. It can be located across side road junctions to give added prominence to the cycle lane, and rotated to face approaching side road traffic.
Design example: advisory cycle lanes in a narrow carriageway |
The replacement of a two lane single carriageway with a single, wide two-way general purpose traffic lane with advisory cycle lanes has been successfully implemented by several local authorities. East Renfrewshire Council applied this technique on a rural carriageway (Eaglesham Moor Road) carrying 1,000 vehicles per day where there was concern regarding high vehicle speeds. The design gives the appearance of a narrow carriageway and encourages drivers to reduce speed and give appropriate space to cyclists when overtaking. Motor vehicle drivers typically give cyclists sufficient space when overtaking and encroach into the cycle lanes when passing oncoming vehicles. This technique has been used in a wide variety of both urban and rural situations. Clackmannanshire Council has applied a similar technique while retaining the centreline (photo left). |
With-flow cycle lanes, whether mandatory or advisory, should be provided in accordance with the lane widths shown in Table 5.2.
Standard |
Width (m) |
Comments |
|---|---|---|
Maximum Width |
2.5* |
Lanes of this width should be used where cycle flows are expected to be >150 cycles/ peak hour and therefore cycles overtaking within the lane can be expected. |
Desirable Minimum Width |
2.0* |
The minimum width that should be considered for a cycle lane with width for cyclists to pass each other. |
Absolute Minimum Width |
1.5** |
The running width of the lane should be free from obstructions such as debris and unsafe gullies. |
* Cycle lanes over 2.0m wide in areas of car parking may attract drivers to park in them. Physical barriers, mandatory lane markings or parking and loading restrictions can prevent this.
** Lane widths narrower than 1.5m can present a hazard to cyclists and motor vehicle drivers. Only in exceptional circumstances should widths down to 1.0m be considered where it is safe to do so – for example where stationary traffic blocks the route to an advance stop line and the proposed lane is safe from obstructions such as gullies.
Sub-standard width or poorly located cycle lanes can provide a false sense of security for both cyclists and motor vehicle drivers and encourage poor lane discipline from both. In many cases, a narrow cycle lane can encourage close proximity overtaking by motor vehicles (Parkin, J and Meyers, C (2009)). Limited space alone is not a reason for providing sub-standard width cycle lanes. Alternative solutions should be sought at such locations.
5.1.4 Adjacent Parking and Loading
Where on-street parking or waiting/ loading areas require to be retained, the positioning of the cycle lane should be considered carefully. Two options are typically available:
A typical layout of an offside cycle lane is illustrated in Figure 5.2. It is preferable that a clearance strip be provided, the width of which should be consistent with the guidance in Table 5.3.
Where double-parking occurs, the effectiveness of an offside cycle lane may be minimal without active enforcement. In such circumstances a cycleway would be more effective.
Table 5.3: Clearance strips between parking and offside cycle lane
Standard |
Width (m) |
Comments |
|---|---|---|
Desirable Minimum |
1.0* |
Ensures that a cyclist does not need to deviate if a car door is opened fully. |
Absolute Minimum |
0.5 |
Will require a cyclist to deviate within the cycle lane if a car door is opened. The cycle lane width in this case should be at least 1.5m, otherwise the cyclist will need to leave the cycle lane to avoid collision. |
* Where required, a clearance strip of 1.5m will permit access for disabled people, without affecting cyclists using an adjacent lane.
Figure 5.2: With-flow cycle lane adjacent to parking/ loading area
Note – For gaps of less than 30m between parking bays, the cycle lane should not be returned to the kerbside.
To prevent motor vehicle encroachment outside of the parking bay area at the tapered hatched ends, consideration should be given to the need for a physical obstruction such as a kerbed area, or double yellow lines to prevent cyclists being impeded.
The default position should be to permit two-way cycling on one-way streets. Where there are safety concerns, the introduction of a contra-flow cycle lane may be required, as illustrated in Figure 5.3. It will be necessary for the one-way street TRO to include an exemption for cyclists.
Because of the potential risk from opposing vehicular traffic the contra-flow lane should be mandatory except across side road junctions. Kerb segregation may be provided at each end of the lane and at intermediate locations if encroachment by vehicles is likely, although street clutter should be minimised. Full kerb segregation may also be considered (Section 5.2).
Figure 5.3: Example of contra-flow cycle lane arrangement
Note 1 - Plates exempting cyclists (Diagram No 954.4) should not be used with a ‘No Entry’ sign (Diagram No 616).
Note 2 - This layout is also permitted without the ‘double D’ islands and with signs to Diagram 619 replacing signs to Diagram No 616.
Note 3 - The provision of a right-turn cycle lane from the major road may be considered where the speed limit is 30mph or less.
5.2 Kerb-Segregated Cycle Lanes
Kerb-segregated cycle lanes can be effective in minimising conflict with vehicles. They are most effective on high speed rural roads and can be provided on an existing road carriageway without the need for a TRO. Transport Scotland has constructed kerb-segregated cycle lanes on the rural all-purpose roads that run parallel to the M77 and M74.
An island of minimum width 0.5m should be provided.
Kerb-segregated cycle lanes should not normally be provided adjacent to vehicle parking or pedestrian activity. In particular, kerb segregation can be a trip hazard or barrier to access for disabled people.
The Desirable and Absolute Minimum widths for kerb segregated cycle lanes are detailed in Table 5.4.
Table 5.4: Kerb-segregated cycle lane widths
Kerb-segregated cycle lane |
Standard |
Width (m)* |
Comments |
|---|---|---|---|
With-flow or contra-flow lane |
Desirable Minimum Width |
2.0 |
Typically operates satisfactorily for flows of up to 200 cycles per hour. The minimum width that should be considered to permit cyclists to pass each other. |
Absolute Minimum Width |
1.5 |
Typically operates satisfactorily for flows of up to 100 cycles per hour. |
|
Two-way lane |
Desirable Minimum Width |
3.0 |
Typically operates satisfactorily for two-way flows of up to 300 cycles per hour and will permit some overtaking. |
Absolute Minimum Width |
2.0 |
The minimum width that should be considered to permit cyclists travelling in opposite directions to pass each other. Operates satisfactorily for two-way flows of up to 200 cycles per hour. |
* The running width of the lanes should be free from obstructions such as debris, unsafe gullies, road markings and street furniture. Consideration must be given to the need for additional clearance distances to fixed objects such as kerbs (Table 6.3). Consideration should be given to an enhanced routine maintenance regime.
A typical layout of this type of facility is shown in Figure 5.4.
Figure 5.4: With-flow kerb-segregated cycle lane
Regular gaps in the segregation island are required to allow access. Location and design of gaps requires careful consideration.
Contra-flow cycle lanes may be segregated from traffic using a kerb island in a similar manner to with-flow lanes, with no TRO required. Section 5.1.5 gives further detail on signing and other requirements associated with contra-flow facilities.
Two-way cycle lanes can be confusing to motorists and pedestrians, however, in some instances these may overcome design issues that are otherwise difficult to resolve. The width of two-way cycle lanes should be as shown in Table 5.4
Issues to consider include:
Nearside bus lanes (with-flow and contra-flow) should be designed for use by cyclists. It is less safe for cyclists to use an offside lane, as this involves traffic on both sides and will require the cyclist to cross the path of buses when making left turns.
Designers of bus priority schemes must consider the needs of cyclists, and include provision for them. Any proposal must be taken forward in consultation with the appropriate transport authorities, bus operators and the police. Additional training on the needs of cyclists is recommended for scheduled bus operators’ drivers.
The recommended widths of with-flow bus lanes are shown in Table 5.5.
The Absolute Minimum width of a bus lane is 4.0m. Bus lane widths of between 3.2m and 4.0m should be avoided as this arrangement encourages unsafe overtaking and will prevent cyclists passing stopped buses within the bus lane. Where the Absolute Minimum width cannot be met, a limiting width of between 3.0m and 3.2m should be provided to prevent overtaking in the lane itself.
Table 5.5: With-flow bus lane widths
Standard |
Width (m) |
Comments* |
|---|---|---|
Optimal Width |
4.6 |
This width allows a bus to pass a cyclist within the bus lane. A 1.5m wide advisory cycle lane may be provided within the bus lane if considered desirable. |
Desirable Minimum Width |
4.25 |
Although a bus is still able to pass a cyclist within the bus lane, safe passing width is affected and this width of lane should only be provided over short distances. A 1.2m wide advisory cycle lane may be provided within the bus lane if desirable. |
Absolute Minimum Width |
4.0** |
An Absolute Minimum width of 4.0m allows cyclists to pass stopped buses within the bus lane but may encourage unsafe overtaking of cyclists by buses, particularly where the adjacent traffic lane has queuing traffic. |
Limiting Width |
3.0 – 3.2** |
The width of the bus lane to prevent overtaking within the lane itself. A bus will be required to straddle adjacent lanes to pass a cyclist, thereby encouraging safe overtaking. |
* Refer to Reid S and Guthrie N (2004) for further information on bus/cycle interactions.
** Lane widths of between 3.2m and 4.0m should be avoided.
Although contra-flow bus lanes can improve safety and convenience for cyclists, care should be used in their development. This is especially pertinent:
Bus lanes and bus routes generally, can be subject to rapid surface deterioration. Damage to the surface discomforts and poses a safety risk to cyclists, causing them to swerve or to adopt a more central position in the road or lane lane than would otherwise be the case. Bus routes and shared bus/cycle lanes should be prioritised for regular inspection and maintenance.
Designers should always seek to minimise both delays to cyclists and conflict with bus vehicles and passengers.
Cycle lanes cannot be taken through a marked bus stop area and should be discontinued over the length of such markings.
However, where there is sufficient space, arrangements such as those illustrated in the examples in Figures 5.5, 5.6 and 5.7 may be considered.
Figure 5.5: Bus layby with continuous cycle lane
Figure 5.6: Cycle lane to rear of bus stop
Figure 5.7: Cycle lane at bus stop boarding kerb
