www bv.com.au More great places to ride Ph 03 8636 8888 1800 773 399 country callers Search [ LATM ] The design of local streets is critical to the health of residents and the quality of life in our cities. A well-designed street encourages walking and cycling by making it easy and safe to get around on foot or by bicycle. better local traffic controls for safer cycling & walking Bicycle Victoria has developed a toolbox to help traffic engineers design local streets that are safer for cyclists and walkers. Local streets are important in the cycle network, but often there is insufficient space for continuous separate bicycle facilities. We show how to safely mix bicycles and motor vehicles on local streets, and how to manage transitions between mixed and separate traffic. For more information Visit www.bv.com.au (Keyword: LATM) You will find Large format versions of the generic intersection design drawings shown in this document A technical paper describing the research evidence behind our recommendations An annotated file of photos of good and bad bicycle arterial design practice from local streets around Melbourne Project funded by: Cities of Moreland, Darebin, Yarra, Port Phillip, Moonee Valley, and the Metropolitan Transport Forum.
Bicycle Arterials on local streets Local area traffic management is meant to calm traffic and make local streets safer, but some devices create risk for cyclists and pedestrians. Causes of increased crash risk on local streets Factors that increase risk of collisions with motor vehicle for walkers and cyclists on local streets are: Fast and unpredictable vehicle speeds Competition for restricted road space Poor visibility to drivers Unpredictable vehicle behaviour Cyclist and walker perceptions of danger correlate well with actual danger (measured by reported crashes). Engineers should seek the views of cyclists and walkers when developing new designs. Cyclists needs Cycle routes should be: direct comfortable visible continuous safe Safety is a priority for riders. But cyclists also want to maintain momentum. Rider behaviour is a trade off of many needs. To ensure that works are used as intended, design must address all rider needs. Bicycle arterials on local streets All roads, particularly local streets, should be safe for cycling. Most local streets serve as local access for bicycles just as they do for cars and trucks. Some local streets are important links in the network of bicycle arterials, especially when provision for safe bicycle travel is difficult on a busy parallel main road. Bicycle arterials should be able to carry many hundreds of cyclists each day. On these routes, right-of-way for cyclists should be maintained at intersecting roads and paths. This document covers the needs of cyclists on bicycle arterials on local streets. The cycle-friendly designs are consistent with improving pedestrian safety and ease of access on local streets. Problems with roundabouts Roundabouts can reduce the number and severity of motor vehicle crashes at an intersection, and they can play a part in lowering overall traffic speeds without the perceived inconvenience and loss of parking associated with humps. But, roundabouts create problems for pedestrians and cyclists that need to be addressed. A generic design for a modified roundabout that improves safety for cyclists is on page 5. Alternatives to roundabouts are usually necessary to improve overall safety and comfort for pedestrians. 1 The standard single-lane roundabout creates risks for cyclists. In Victoria, 5.2% of all bicycle casualties occur at roundabouts, although roundabouts make up only a small proportion of all intersections. Most crashes appear to be due to drivers failing to see and give way to cyclists already in the roundabout. More than 40% of crashes were on singlelane roundabouts on local streets. 2Standard roundabouts create an unpredictable speed environment. Roundabouts present drivers with more opportunities to drive on the basis of acceleration and aggression than is possible (with other intersection controls). [Allot & Lomax, Cyclists and Roundabouts, CTC, (UK) 2nd ed.,1993] Roundabouts can increase the speed of some vehicles. For example, if a roundabout replaces a stop sign, traffic on the low priority street vehicles can accelerate into the intersection. This is inappropriate when traffic is crossing a bicycle arterial. 3 Roundabouts disadvantage pedestrians. Pedestrians must give way to all vehicles on all legs of a roundabout, making it harder to cross. Roundabouts remove footpath space and make walking longer and less direct. Avoid installing new roundabouts if possible. Raised tables are preferred for cyclists and pedestrians. Many roundabout layouts include substandard painted bike lanes that force cyclists into dangerous positions on the road. The safer way to ride in a roundabout is shown in this picture. [2] Better local traffic controls for safer cycling & walking
Creating a cycle-safe street Reduce vehicle speed to 30kph OR make separate space for bicycles The most effective way to make local streets safer for cycling and walking is to reduce the speed of all vehicles to a human scale : 30kph or below. Below 40kph, crash impacts are not likely to be fatal. A cyclist might be expected to contribute at least 10kph to the combined speed of a collision with a motor vehicle. So, vehicle speeds need to be kept below 30kph. If speed cannot be reduced to 30kph, then separate space must be provided for cyclists on the road, and safe crossing-points provided for walkers. There are two safe types of bicycle arterial on a local street. 1 SEPARATE Continuous separate space for bicycles where cycle speeds of at least 20kph can be achieved safely and consistently. A continuous painted cycle lane is acceptable in 50kph car traffic. Even where traffic speeds and volumes are low, painted lanes create visible space for bicycles. 2 MIXED A calmed street where bicycles can safely share the same road space as motor vehicles. Maximum traffic speed must be kept to 30kph and traffic volumes kept below 2,500 vehicles per day. Mixing bicycles and motor vehicles In mixed traffic, the cyclist leads the way. The road layout must make it clear that the cyclist should ride in the centre of the lane and that squeezing past a cyclist is not permitted. Most local street intersections do not have space for separation of bicycles and motor vehicles. Safe mixed conditions must be created. Separate to Mixed transitions When a street narrows, cyclists may make a transition from a separate to a mixed environment. This transition must occur in a predictable way, with sufficient space and with traffic speeds constrained below 30kph. In many current road layouts, a rider is forced to make the transition from separate to mixed space close to an intersection and/or where cars are travelling faster than 30kph. This maximises the risk to cyclists as the travel paths of bicycles and cars are not predictable and the difference in speeds is too great. Transitions in an intersection approach On a bicycle arterial, transition from separate to mixed space should be made before an intersection or narrowing. After the transition, cyclists and motor vehicles will share the same space and so maximum possible traffic speeds must be kept below 30kph. If a speed cushion or hump is used to slow vehicles before the mixing point, then this should be placed up to 40m from the intersection to prevent re-acceleration before the intersection. MID-BLOCK APPROACHING INTERSECTION IN INTERSECTION ( mixed traffic) Separate Wide road (marked bike lane) or Off-road cycle facility (20kph design speed for cycles) Mixed Narrow road (No marked bike lane; designed so maximum possible vehicle speed is 30kph) 40m before intersection or narrowing Reduce vehicle speed below 30kph and design space for bikes to make transition to mixed environment. Low vehicle speed (<30kph) Predictable vehicle trajectory Sufficient space for bikes Figure 1: Transitions from mid-block to intersection on a cycle-friendly local street Better local traffic controls for safer cycling & walking [3]
Which design where? Intersections on a bike arterial Roads crossing a bike arterial will be of different widths and will carry different volumes and types of traffic depending on their place in the road hierarchy. For each intersection type, we recommend a generic type of LATM treatment that provides the appropriate level of priority and risk reduction for the bike arterial. The generic designs are illustrated on the opposite page. Status of cross-street Possible treatments on Appropriate LATM treatment in road hierarchy cross-street at intersection Residential Speed cushions or humps in intersection Intersection 3 preferred treatment (Up to 11m, up to1,000 vpd) approach Intersection 2 (consistent but expensive) Intersection 4 Not roundabout Roundabouts are designed for intersections that carry similar volumes of traffic (bicycles or cars) on all legs, so are seldom appropriate where a bicycle arterial crosses a residential street Narrow Collector As for wide collector, but with speed Intersection 2 preferred treatment (Less than 14m, around cushions in intersection approach Intersection 1 2,500 vpd) signals Wide Collector frequent crossing opportunity For example, Intersection 1 (14m or wider, more nearby signals that allow 30-second gap in traffic signals than 2,500 vpd) every 2-3 minutes splitter islands splitter islands one-way signals Arterial (Not addressed in this document) (Not addressed in this document) Possible treatments include: one-way signals, closures, grade separation (over or under), or short detour via shared path to signals. FOR FURTHER INFORMATION Austroads Guidelines to Traffic Engineering Practice Part 14, Bicycles (1999) & Part 10, Local Area Traffic Management (draft, 2003) It Can Be Done, Bicycle Victoria (1996); www.bv.com.au (Keyword: It can be done) VicRoads Cycle Notes 1 12; www.vicroads.gov.au [4] Better local traffic controls for safer cycling & walking
Cycle safe designs: intersections cross street 1 bicycle arterial Intersection 1] modified roundabout Approach includes transition to single mixed traffic lane: - 20kph speed cushion/hump in traffic lane up to 40m from give-way line - bicycle lane merging into 3.0-3.3m traffic lane downstream of speed cushion 150mm high rollover kerb to separate parking lane from mixed traffic lane Elliptical centre island Bicycle arterial width: sufficient for bike facility 2 bicycle arterial Intersection 2] raised table Stop on cross-street Stop line position dependent on sight lines 1 in 12 gradient on table: will require painted piano keys on slope Bicycle arterial width: not sufficient for separate on-road bike facility Gap in cushions for bicycles: 0.9m cross street 3 bicycle arterial Intersection 3] plateau on cross street Location of plateau in relation to stop line dependent on sight lines and location of footpath If plateau is not painted with piano keys, then maximum gradient is 1 in 20 Bicycle arterial width: not sufficient for separate on-road bike facility Gap in cushions for bicycles: 0.9m cross street 4 bicycle arterial Intersection 4] half closure Higher volumes of traffic (including bikes) on bike arterial, so stop signs are placed on cross street Bike lane painted through intersection Bicycle arterial width: sufficient for bike facility cross street Better local traffic controls for safer cycling & walking [5]
Cycle-safe designs: mid-block 1 Mid-block 1] 20kph humps and speed cushions with gaps for bicycles North Terrace, Clifton Hill, Melway 2C H2 2 Mid-block 2] vertical displacement with bypass Attention required in design and construction to achieve smooth surface of bicycle bypass and where bypass ramp meets road. (This example could be improved by providing a smoother and wider gap for bicycles.) Camden Street East St Kilda, Melway 2P H9 3 Mid-block 3] horizontal displacement with bypass Attention required in design and construction to achieve smooth surface of bicycle bypass and where bypass ramp meets road. (This example could be improved by providing a smoother and wider gap for bicycles.) Tennyson Street, St Kilda, Melway 2P E10 4 Mid-block 4] full closure Acceptable width for bypasses is in the range 1.0-1.8m in each direction. 1.5m is recommended. Napier Street, Fitzroy, Melway 2C B10 See www.bv.com.au (Keyword: LATM) for more examples [6] Better local traffic controls for safer cycling & walking
Design details Lane widths The traffic lane in a mixed environment In a mixed environment, cyclists take space in the centre of the traffic lane to prevent unsafe overtaking. Lane width should not encourage a driver to try to squeeze past a cyclist within the lane. The recommended lane width is 3.0m, with an acceptable range of 2.8-3.3m. Lane widths in LATM treatments When used in separate traffic environments, chicanes and narrowings should be built with cycle bypasses (see below). LATM devices with horizontal displacements and lane widths greater than 3.9m may not need bypasses, but such devices are unlikely to adequately reduce vehicle speeds. The recommended lane width in narrowings and roundabout approaches is 3.0m, with an acceptable range of 2.8-3.3m. Trucks and emergency vehicles can be accomodated with rollover kerbs. Many current treatments provide substandard width cycle lanes in the entrance throat or circulation space of roundabouts and in road narrowings. This is unacceptable. Cyclists are being asked to take a vulnerable position exposed to traffic that is too close and too fast. Cycle bypasses Where vehicle speeds and volumes cannot be constrained within mixed traffic standards, bypasses should be provided at narrowings. Where humps, tables, or other vertical displacements are used in large numbers, bypasses or cut-throughs improve cycling comfort and speed. The recommended width of a cycle bypass is 1.5m, with an acceptable range of 1.0-1.8m. Greater than 1.8m allows cars to use bypass. The principal design considerations are: minimal change of direction (cyclists should not be required to make any sharp turns in the vicinity of a LATM device); prevention of parking over entrance and exit (10-15m clear of parking); locating bypass to minimise potential conflicts with vehicles as cyclists rejoin main carriageway and to allow clear sight lines. Visibility of cyclists A number of factors contribute to the invisibility of cyclists to drivers. These include: the path taken by cyclists the direction and timing of drivers observations of other road-users drivers expectations of the behaviour of other traffic Invisibility is a danger for cyclists whenever they are in a position on the road that is not obvious or clearly anticipated by drivers. Signifiers like line-marking and painted lanes are particularly important at full or partial road closures and near other LATM devices. Care is needed with sight lines at vehicle holding lines. Specific needs of walkers In addition to the safer environment created by lower vehicle speeds and appropriate crossing points, design of walking routes needs to provide: A choice of route to keep the trip interesting Protection from extreme sun and cold winds An even surface with few barriers Smooth ramps at crossing points The opportunity to combine a number of reasons for a trip into one journey Better local traffic controls for safer cycling & walking [7]
Better local traffic controls for safer cycling and walking Process flow chart Identify opportunities for improvement or location requiring action (road re-construction program, safety audit of bicycle routes, etc.) Identify place of street in local cycle network: is it a bicycle arterial? Also, identify place of street in road hierarchy for motor vehicles. Assess traffic speeds and volumes. Are these acceptable within intended road hierarchy? If not, what is target speed and volume? Assess existing or potential cycle volumes: include bicycle numbers in traffic volumes on a bicycle arterial. Examine road widths and current layouts. What options are available to reduce traffic speeds? Does space exist for a separate environment for bicycles that allows continuous safe cycling space at minimum 20kph cycling speed? (If actual vehicle speeds are consistently around 50kph, then the minimum acceptable design is on-road painted cycle lanes.) YES Create safe, separate and continuous cycle facility. Provide for the transition from separate (marked lanes) to mixed 30kph environment up to 40m before intersection or road narrowing. NO Create a safe mixed car and bike environment with maximum vehicle speeds of 30kph. Check design for cycle safe requirements. Consult cyclists Significant displacement is needed in LATM treatment to achieve 30kph maximum speeds. Where space is constrained, vertical displacement is more convenient Maintain cyclist comfort & momentum with direct cycle bypasses or gaps 1.0-1.8m wide. Traffic lane widths In 30kph zones, the standard traffic lane width should be 3.0m. In narrowings without bypasses and in roundabout approaches, traffic lane width should be 3.0m. (Cover photo Canning Street Carlton Melbourne) Close spacing of devices To maintain a 30kph zone, LATM treatments will need to be spaced at 50m intervals. For more discussion of spacing, see ARRB (2003) Austroads Project Report, Guide to Traffic Engineering Practice Part 10 Local Area Traffic Management (draft), p. 79 Visibility Coloured lane-marking is a valuable tool to improve driver expectation of the presence of cyclists. Design features should ensure that bicycle behaviour near LATM devices is direct and predictable and that sight-lines are clear for all road users. Pedestrians Are adequate crossing points provided for pedestrians? [8] Better local traffic controls for safer cycling & walking www bv.com.au For more info Ph 03 8636 8888 1800 773 399 country callers Search [ LATM ]