What makes good bicycle tracks

I have already written here that most bicycle tracks in Tartu are of unacceptable quality.  Too often they are not direct, not smooth, and in places too narrow.  As it seems, the planners do not understand the basic needs of cycling.  Here I explain a little.

Bike track in Aarhus, DK.  It is smooth, and it goes straight across the junction.  The same priority rules apply both for cars and cyclists.

First, safety is important but not all-important.  I have seen claims that safety is almost the sole characteristic of the bicycle traffic. This is simply not true.  Bike tracks are not (just) about safety. They are about a combination of safety, accessibility, smoothness, and speed.  If safety were the all-important requirement, we would never cycle, never walk nor even drive small cars.  But we do.  We accept a low risk of injury if this helps us smoothly to get where we want to go.

Junction of Riia and Raudtee streets.  The bicycle track ends here abruptly at a guardrail (center).  The cyclists are supposed to take a sharp turn right, then left, cross the street at pedestrian speed, and continue on a very narrow sidewalk (right).  It is a safe but very inconvenient solution. A car lane at the same place (left) has neither abrupt turns nor other obstacles.  As the street goes downhill, cyclists can easily achieve speeds here comparable to those of cars.

In order to improve the biking conditions, one must plan the lanes with this suitable combination in mind.  If cycle lanes are very safe but the ride will not be fast and smooth, people will not choose cycling (or choose to cycle elsewhere).  In practice, the picture is complicated by the heterogeneous preferences by cyclists.  Broadly, kids and slow rider prefer safety, fast riders smoothness.  But it is perfectly possible to cater to all of them in most cases.  Usually it is achieved through street hierarchy—slow speed is enough inside a city blocks but large thoroughfares should allow full speed cycling (at least 30km/h).  Cyclists are exactly like motorists from this aspect.

Left: bike track between Maarjamõisa hospitals and University biomedical center.  Except for a few curbstones, this stretch is adequate for short-distance connection inside the university campus.  Due to it's location, it cannot be upgraded for high-speed connection between different parts of the city.  Right: bike track next to a major thoroughfare, Võru street.  Unlike cars, cyclists are supposed to yield at the small sidestreet and take an inconvenient turn just after the junction.  This is a place where the track should be upgraded to allow full-speed cycling.

Second, road users are always interacting and have to adjust to other road users.  This is partly achieved through planning of roads and junctions.  It is important to realize that adjustment is costly, usually involving breaking and speeding up again, and often maneuvering.  Current cycle tracks put too much of these adjustment costs on cyclists.  The tracks almost never go straight across intersections, even at the main thoroughfares, often forcing bikes to slow down to walking speed in order to cross curbstones and take sharp turns.  Second, instead of dedicated bike lanes, cyclists are often expected to ride on pedestrian walkways.  This is an acceptable solution only if these are wide and not crowded.  The most critical points are typically bus stops, turns around street corners, and areas near pedestrian crossings.  Sidewalks in these places are often narrow, visibility low, and many people standing and waiting.  Now compare this with the car lanes at the same stretches.  Those almost always retain their width, there are hardly ever obstacles like curbstones, and they go straight across the junctions.  Most of the the adjustment costs are shifted to cyclists and pedestrians.

Seems like the planners mainly follow two aims: the lanes must be safe, and the motorists should not bear the adjustment costs. Unfortunately, this leads to unusable cycle tracks.

Bicycle Lanes in Tartu

The last decade has seen a number of dedicated bike lanes built in and around Tartu.  Unfortunately, their functionality is rather limited. Below I explain why.
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There are different cyclists.  In the one end we have slow local riders like children but also adults pedaling only a few blocks.  At the opposite end are regular fast commuters who move distances around 10km.  (I ignore bicycle racing and related issues here.)  Below, I explain what are the main problems with the existing lanes, in particular for the commuter group.

Junction of large roads as it ought to be: Nordre Ringgade crossing Nørrebrogade in Aarhus, DK.  The bike lane is just at left of the photographer, the markings are visible on street.  Note the lane is straight, and there are no curbstones.

First, the bicycle lanes should be straight.  The lane should be free of pylons, traffic lights but also pedestrians, and avoid unnecessary sharp turns.  In my opinion, this is the most problematic side of the current lanes.  All too often they are bent away from the street at junctions, and the bend typically includes a combination of a sharp turn, high curbstones and a
guardrail.  Hence one cannot cycle at typical speed for faster riders, 20-30 km/h, even along the major thoroughfares (like Võru street or Räpina road).

This is how it works in Tartu.  The guardrail works as a barrier and does not allow unhindered cycling.  But note the ongoing construction further down—the bend on the car lane is being smoothed out.  Junction of Tartu-Ülenurme road and Kuslapuu street (right).

Note that one almost never encounters such obstacles on car lanes.  It is also a safety issue, making cyclists less visible and rendering the right-of-way unclear.  Similarly, the existing cycle lanes almost never allow full-speed entry and exit.  Fast riders, notably out-of-town, cannot take sharp turns.  Hence the short dedicated tracks are seldom usable—the tiny gain in safety does not justify a large loss in speed.

Junction of large roads done wrong.  This is right-turn-lane of Aardla street joining one of the main thoroughfares, Võru street just ahead of us.  Note that just on this picture, cyclists are supposed to cross two curbstones and take a 90-degree turn on a rather narrow lane.  The only way to cross this junction at typical bike speed is to stay away from the bike lane.

Unfortunately, I have not experienced any improvement here over the years.  Even the newest tracks, like the one along the Räpina road, expect too much maneuvering and yielding from the cyclist.  Note that straightness is less of an issue for slow-speed local riders.  Hence the current quality of the track network may well cater for that group.

Second, the lanes should be direct and broadly follow the shortest path between the main destinations.  This is often a thorny issue as the shortest paths are typically occupied by large streets. For instance, neither Riia, Narva nor Võru streets have any dedicated cycle lanes despite offering direct access between large stretches of the city, and being often considered too dangerous for biking.  The suggested alternatives, Kesk street next to Võru and the way over Näituse street to reach Maarjamõisa hospitals, are substantially longer.  Directness matters for everyone, despite their distance and speed.

Third big issue is evenness.  Even street surface is a must.  The most problematic point here are the curbstones, but also the overall profile of the lanes.  A high-quality bike lane should not have any curbstones in the first place.  Second, the surface profile should be smooth enough.  If certain sections must be lower (for instance, to facilitate driving across the sidewalk), one should smoothly lower the lane level along a longer stretch.

Junction of a major thoroughfare, Võru street with a sidestreet.  Note three problems here: the surface is not smooth enough even given sunken curbstones; the curbstones on the street side cannot be crossed at all, essentially cutting the width by a third; and finally the profile is too steep even behind the curbstone.

Finally, particularly on the older roads, the quality of pavement is also an issue.  Fortunately, here a clear improvement is visible over years.  Evenness matters more for fast riders, but the curbstones also hurt the slow ones with small wheels, like children.

The final issue is the lane width.  In general, the lane should permit for two cyclists to ride next to each other.  This is especially important with children (the parents want to "cover" the street side), or for overtaking slower cyclists.  True, such 1.5-2m wide lanes are not feasible everywhere.  But one should avoid unnecessary bottlenecks.  Far too often the guardrails, traffic lights, and improperly installed curbstones narrow down otherwise adequate lane.

Bus stop done well.  Nordre Ringgade, Aarhus, DK.

Bus stop not done well.  It expects too much maneuvering in a narrow section of the bike lane.  One of the main thoroughfares in Tartu, Võru street.

A specific problem is posed by bus stops.  These are frequently located at a particularly narrow section of combined sidewalk/cycle lane where the shed and waiting people also take up space.  Bus stops require extra wide, not extra narrow lanes.  Inadequate width hurts more the fast riders.

Nordre Ringgade crossing Aldersrovej near Trøjborgcenteret.  All done well: no curbstones, the cycle lane retains it's width, and the profile is smooth.

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Virtually none of the existing cycle lanes around Tartu follow these standards.  The quality has been improving from the perspective of slow riders but for long-distance cyclists the lanes are simply inadequate.  Realistically, I would recommend the planners the following:

• Rename the current cycle lanes to "cycling-enabled sidewalks". Permit cycling there given one does not endanger pedestrians.  For faster riders, permit cycling on the car lanes as well.
• Understand the different types of traffic.  Lanes for slow-speed riders need not to follow the same standards as high-speed thoroughfares.  Think what kind of traffic is dominating on certain streets.
• Most importantly, before designing the next traffic project, learn about the capabilities and requirements of cyclists!  Bike lanes are costly, and if not constructed properly, they may be more of a hindrance than help for cyclists.