Desire lines

No, not the lines of people trying to pay for their shopping. Desire lines are lines drawn on a map that represent where people desire to go. When planning and designing infrastructure for active transport (especially pedestrians), desire lines are an essential indicator of how people will want to use the facility. This is because it may take extra effort to deviate off the route that gives you the shortest path to your destination. The less mechanical assistance you have, the more important the shortest path is to route choice.

It is important to realise that the shortest path is not necessarily the route that has the shortest distance. It tends to be the route that appears to be the most direct path to the destination from a point of decision. For the pedestrian this is usually the route that follows the 'line of sight' - a path that most closely matches a straight line route from where you stand to where you want to go.

When planning and designing active infrastructure you ignore desire lines at your peril. Here are two examples. 

The first is an old one that I see every day I ride to work. It is the link across Little Dock Street between the Kangaroo Point Bikeway and Vulture Street. This link is restricted as I bicycle-only connection. The planning intent was that pedestrians wanting to access Vulture Street would cross Little Dock Street at the Goodwill Bridge and use the bougainvillea pathway. Cyclists would use the Kangaroo Point Bikeway and exclusively use the link across Little Dock Street. sort of like the illustration below. The Kangaroo Point Bikeway and the pathway alongside it were designed with fences, kerbs and signs to ensure people stick to this arrangement.

All very nice and neat. However, this arrangement neglects to recognise that when walking people make their routing choices based primarily on desire lines in order to expend the least effort in reaching their destination. The infrastructure and regulation are only considered where they physically prevent a movement, or when the 'self-preservation' instinct overrides the 'least-effort' instinct.

The desire-lines for pedestrians between the Goodwill Bridge and Vulture Street can be shown as below. In addition to this major desire line there is also a minor pedestrian desire line between Vulture Street and the pathway going east along Little Dock Street.

The resulting pedestrian movements result in significant conflict between pedestrians and cyclists along a very narrow section of separated pathway (only 2m wide cycleway).

For the most part pedestrians recognise that they are crossing the bikeway and they are careful to not get in the way. They check before they cross and keep their eye out to avoid conflict, as can be seen in the picture below. Note the pedestrian in the background is also keeping an eye out to avoid conflicts on the narrow path.

In fact it is such a well-worn route that you can see the path through the vegetation that pedestrians take to avoid being in the way of cyclists.

But often this does not happen and conflict erupts. I almost witnessed a fist fight recently where a rather muscular pedestrian who had been walking in the middle of the bikeway shoved a cyclist when he tried to get past after ringing his bell. Usually this sort of conflict just results in some rude words being exchanged as the cyclist and pedestrian exchange their feelings of mutual dislike for each other. That time (and I am sure there have been many others) it could have ended tragically.

The solution to this is relatively simple, but will cost some money. What is needed is to provide sufficient space for both pedestrians and cyclists to make the link between the Kangaroo Point Bikeway and Vulture Street. More fences and signs will not solve the problem, it will just make it more frustrating for all users.

The next example is a more recent one - the landing of the Kurilpa Bridge on Tank Street. When designing this landing the engineers had great difficulty fitting in all the pedestrian, cyclist and vehicle movements. The complicating factor was the driveway off Tank Street for access to a parking garage. This wide driveway was adjacent to where the bridge landed and spills its load of pedestrians and cyclists. The designers came to the conclusion that the driveway entry and exit meant it was not possible to provide sufficient space to store pedestrians wanting to cross Tank Street. The large number of vehicles using Tank Street to access parking garages would have been too severely delayed by creating a shared zone for pedestrians and vehicles.

So the solution delivered was to prevent pedestrians and cyclists from crossing Tank Street where the bridge landed. A wall was constructed to prevent this movement and gardens planted to make it clear that pedestrians should not cross here. Fortunately as a compromise a speed hump was included on Tank Street to slow drivers down as they approached the parking lot driveway.

Unfortunately the pesky pedestrians had not studied engineering and they refused to comply.

 They just didn't seem to realise that this was not an approved maneuver.

 Within no time they had worn a path through the landscaping that was intended to prevent them from crossing.

Unfortunately the designers ignored the very obvious desire lines. The approved place to cross Tank Street was determined to be at North Quay and George Street (as below). That would ensure that any conflicts that would occur could be controlled.

What this design ignored was the very strong pedestrian desire lines between the coffee shops (and parking garage) on the north of Tank Street, and the offices and bridge on the south. It also ignored the fact that the proposed path between North Quay and the Kurilpa Bridge or south Tank Street was not at all obvious and was not on the pedestrian (and cyclist) desire line.

 So of course this resulted in pedestrians (and some cyclists) making 'unsafe' maneuvers.

 Thankfully a solution was retrofitted that better provides for pedestrian and cyclist desire lines.

It is unfortunate that desire lines were ignored in the initial design, as I am sure that a more elegant solution could have been found to this problem.

Cyclists needs

A presentation by John Offer (from the City of Stirling) to the WA Cycling Safety Forum has some interesting approaches to the needs of users and appropriate treatments to cater for them (follow the link to see it). In Western Australia cyclists older than 12 are not allowed on the footpath. The intent of this is to minimise conflict between pedestrians and cyclists. But John rightly points out that many adult cyclists have very similar riding styles and confidence/skill levels as younger cyclists. They are therefore proposing to allow adults to cycle on footpaths as long as they are slow. To reduce the speed of cyclists on pathways they are trialing a 'Stirling Gate' - photo below.

It would be interesting to find out how that has performed.

With regards the types of cyclists he uses three groups - the 12-year old cyclist, the casual adult or POBSO (don't know what that means), and the Adult experienced cyclist group or commuter. My personal preference is the classification I developed after reviewing several alternatives (including 'The Principles of Cyclist Network Planning’ Land Transport NZ). 

Type of cyclist	Description
Beginner	Beginner cyclists include young children and novice cyclists. They can be unpredictable and prefer full separation from other traffic, particularly when travelling along busy roads. Trips by beginner cyclists are commonly to school and shops and for pleasure near their homes or in recreation areas. Beginner cyclists often find it difficult interacting safely with vehicle traffic when not on traffic-calmed local streets. They prefer grade-separation or signal controlled intersections when crossing busy roads.
Cautious	Cautious cyclists include those with basic competence and more experienced cyclists who are risk averse. Cautious cyclists prefer separated cycle facilities but can ride on quiet two-lane roads, can manoeuvre past parked cars, and merge across and turn right from beside the centre line. They can cope with simple traffic signals and single-lane roundabouts that are designed for slow through traffic. When required to travel on busy roads, cautious cyclists prefer cycle lanes and facilities at intersections. They are not well equipped to interact with faster traffic, multi-lane roads and multi-lane roundabouts. They usually lack the confidence to defend a lane where the lanes are too narrow to share. Cautious cyclists are willing to use alternative longer routes in order to avoid situations perceived as high risk.
Confident	Experienced cyclists interact assertively with traffic. They do not require specific cycle facilities, only the space on the road when in amongst faster/busier traffic situations. Experienced cyclists will defend a lane where there is not enough room, judge the merge across faster multi-lane traffic, use multi-lane roundabouts in most cases (though apprehensively), and will not usually divert to a cycle path unless it provides a higher level of service than riding on-road.

I like this classification because it does not confuse the trip purpose, age or experience of the rider with their needs. Any classification that has a category 'commuter' does not recognise that commuters can range from novice cyclists to confident cyclists and the network needs to account for the needs of all to maximise the potential to promote cycling.

The need for speed

I enjoy my 8km cycle commute to work and occasionally try beating my best time for the commute. But speed often gets me, and others, into trouble. The bikeway is a fantastic way to get to work but it can get a bit crowded. Since I cycle in from the south east most of the route has cyclists and pedestrians sharing the path. In some of these cyclists travelling at speed are a major hazard - to themselves, pedestrians and other cyclists. Sections like the Goodwill Bridge, Victoria Bridge, Southbank and the old Bicentennial Bikeway have so many cyclists, walkers and runners that things can get a little hair raising during peak commute times.

I sympathise with the idea of a pro-cycling Perth political to implement speed limits for cyclists as reported in this article. The problem is, they are not really practical. Cyclists are not legally required to have speedometers fitted so there is no way they can know whether they are travelling over the speed limit. I have not checked the road rules but I suspect that it would be impossible to fine a cyclist for speeding. It is more likely that they would be fined for reckless or dangerous cycling.

Speed only really is an issue where there is potential for conflict between pathway users travelling at different speeds. The risk of conflict is increased as the space per user decreases, and the speed differential of users increases. Which is why the guidelines recommend that pathway width increase on busy shared pathways, or users are provided with separated pathways where conflicts are high.

There may be a need for guidelines to recognise that the speed differential of cyclists is also a risk. Busy rural roads have passing lanes to allow fast cars to bypass caravans and slow trucks. For cyclists the equivalent would either be a wider cycleway (as recommended in the Cycling Super Highways) or providing both on-road and off-road options. The former may be preferable but the latter may be the pragmatic answer that is implementable.

A 3m wide shared path and 1.5m wide bike lanes is often far more palatable for roads engineers than a 6m wide shared pathway. But effectively cyclists have the same amount of space allocated to them. And by separating the shared pathway and cycle lanes there is potential that confident cyclists with a need for speed will choose the bike lanes while the slower cyclists and pedestrians share the pathway.

This is all conjecture as I have not seen any research on this. But something worth considering when deciding on the appropriate solution for a corridor.

Buffered bike lanes

Check out this fantastic video produced to educate the public about Portland, Oregon's installation of buffered bike lanes, something used quite extensively in New York (thanks to Peter Berkeley for sharing this link on Facebook).

On the Right Track from Mayor Sam Adams on Vimeo.

Here is a picture of a buffered bike lane in New York showing what it should not be used for. Note the potholes and drainage grate - they didn't get everything right.

What I find interesting in the video is the bridge in the background as Mayor Adams talks. It would appear to be a vehicle bridge that has one lane used by cyclists and pedestrians but I see no marking on the road to delineate this. I Googled and found a Streetfilms video on the Bridge - it is Hawthorne Bridge. It is clear in the video that it does have a kerb between the cars and bikes but interestingly no railing. Considering the obvious capacity issues on the ped and cycle section this seems a bit risky.

The bridge carries 7,200 cyclists per day which is 20% of the traffic on the bridge and it would appear that there are many pedestrians on the bridge too. Any conflict between cyclists or with pedestrians could catapult a cyclist straight into traffic.

Interesting fact I gleaned from the Streetfilms blog is that the number of cycle commuters in Portland has increased 600% in the last 15 years. If you build it, they will come (as said in the video)

Swanston Street redevelopment

I posted previously about how the Melbourne public supports a car free Swanston Street. The plans remove car parking and give cyclists a 2 meter wide bike lane next to the trams in both directions. The redevelopment will be completed by 2013 costing $25.6 million according to an article in The Age. The Council's media release says that the redevelopment of Swanston Street will have:

• A 24-hour ban on all cars (excluding taxis and authorised vehicles) to be implemented during 2010
• Taxis to be banned from mid-2012
• Four new public spaces with disability-compliant tram stops
• Tram tracks lowered and the bluestone and granite paving extended to the platform edge
• Two metre wide bike lanes – road rules will apply, cyclists must give way to tram passengers
• Service and delivery vehicles at restricted times in limited sections of the street
• New and consistent lighting, additional trees, florals, artworks and public seating installed along the street
• Additional pavement-based activity including outdoor cafes and innovative retail encouraged
• It remain Melbourne’s premier civic parade street.

This is a big win for pedestrians and cyclists although the shared space for cyclists and tram passengers at the stops is likely to be a major conflict point and will need to be watched. Pedestrians are already used to keeping an eye out for cars but once they are removed from the street will they remember to look out for cyclists before crossing?

The proposal was to be presented to Council on 2 February but no news yet as to decisions. What is interesting about this is the Lord Mayor's admission that his original views on returning cars to Swanston Street were wrong. He calls it his 'road to Damascus' where he 'saw the light'. Part of his conversion could be thanks to meeting New York's Mayor Bloomberg and seeing how he has given some of the busiest intersections in New York to pedestrians and cyclists and in doing so reduced congestion. Paul Steely White commented that New York's example can convince other cities to look after pedestrians and cyclists. This proves him right.

From a visit in 2008 I would say that cyclists and pedestrians on St Kilda Road around Flinders Street Station would welcome a bit more space at the expense of cars. Bicycle Victoria confirms that this is one of the most popular routes and dangerous spots for cyclists in the city.

Infrastructure safety

Michael Langdon brought to my attention an interesting literature review on the impact of infrastructure on bicycle injuries and crashes. The paper looked at safety at intersections and between intersections worldwide. The paper provides a useful overview of international research into cyclists safety with an interesting overview of the research reviewed.

The majority of the literature on intersections dealt with roundabouts. As would be expected the research found that multi-lane roundabouts are hazardous to cyclists. Separating cyclists from traffic at roundabouts, either through lanes or separate paths, improved the safety of roundabouts for cyclists.

The research shows that the most hazardous place for cyclists is on the footpath. This would seem counter-intuitive to most parents who usually advise their children to use the footpath. Unfortunately the paper does not go into this in more detail but it does indicate that much of the risk is due to cyclists entering intersections and crossing driveways in the opposite direction to traffic.

The research shows that the safest place for a cyclists is on a purpose-built cycle facility (cycle route, cycle lanes, cycle paths etc). Cycling on road was found to be less dangerous than cycling on the footpath with pedestrians. There are several Internet articles that discuss this subject including this one by Ken Kifer and they all agree: footpaths are dangerous places to cycle.

From this it is clear, providing a cycle lane on a road may be safer than providing a wide footpath. If there is a need for cyclists to be accommodated off-road it is essential that a purpose built facility is provided that adequately addresses safety for cyclists in the design, especially at intersections and driveways. Just widening the footpath is likely to increase the risk to cyclists unless the major areas of risk, at intersections and driveways, is not adequately addressed.

Cycle paths and bus stops

Here is an interesting treatment Copenhagen uses for getting separated bicycle paths past bus stops. Nicely described by Copenhagenize.com
Judging by the way bus passengers are standing in the bicycle lanes I would expect this sort of treatment to result in significant conflict between bus passengers and cyclists.