THE PROPER BUSY STREET DESIGN--PROTECTED BICYCLE LANES (CYCLE TRACK) WITH ROUNDABOUT INTERSECTIONS WHICH INCLUDE SEPARATE BICYCLE PATHWAYS
Today Vermont and the nation
face the reverse dilemma encountered by Western European nations a half-century
ago and now only mostly resolved. Then
Western Europe with the bulk of urban trips by foot, public transit and bicycle
faced an invasion of cars on street systems which in many cases dated from the
Middle Ages. Europe largely solved their
dilemma through innovations ranging from modern roundabouts, traffic calming,
cycle track (protected bicycle lanes) and “shared space.” An equilibrium now exists there in the modal
shares with car travel in some areas still a minority of urban trips with walking and
bicycling trips even increasing their shares.
Today Vermont like the rest
of the nation operates in the beginning of an urban transportation revolution
with rapid growth in walking, bicycling and public transit modes—but from a
tiny base shares, less than one percent share for bicycle trips, just over
three percent for walking trips, slightly over six percent public transit and
overall ten percent for these three modes
Since government controls
practically all walking, bicycling, bus and rail passenger infrastructure and
investments, the urban transportation customer who demands immediate changes to
enable their new choices faces a stodgy, unresponsive governmental
landscape. And too often that landscape
set of choices involves increased risk to life and limb.
The walking and bicycling infrastructure
stovepipes
Two key types of new
infrastructure of great benefit to walking and bicycling modes—roundabouts and
cycle track—arose from separate and distinct histories. Roundabouts arose in 1966 in the U.K.
primarily as a means of moving more cars with less car occupant injuries—the
fact that walker injuries sharply declined and at most a minor gain in
bicyclist safety got treated as a side benefit. Cycle track—now a Western European
staple—grew from increased cyclist carnage on busy streets when car travel
increased. Yet, roundabouts and other
walking and bicycling infrastructure appeared to develop along separate
parallel lines. The connection between
cycle track primarily benefiting cyclists of all skills and roundabout
treatments--which one can argue arose primarily meet the safety and service
needs of walkers--remained to a great extent evolving within their own separate
stovepipe.
So, in a sense there has
existed a “roundabout” stovepipe and a “cycle track” stovepipe. Sidewalks for walkers and cycle track for
bicyclists now represent a generally accepted approach for street segments, and
several U.S. cities, particularly Chicago now in the midst of installing 100
miles of cycle track leading the development.
Meanwhile, the bicycle community justifiably found the larger earlier
roundabouts in the U.K. still highly crash prone and that legacy of concern
spread to other nations. Research finds
bicyclists injury rates decrease significantly over alternatives with single
lane roundabouts and slight safety increase at smaller two-lane roundabouts.
Roundabouts came to the
United States in 1990 and now number about 4,000. Roundabout performance included an overall
reduction in serious injuries and fatalities of about 90%. But for those who walk and bicycle,
safety—particularly at multi-lane roundabouts—remained a concern. The “roundabout stovepipe” did not address
how to serve all skill levels of bicyclists in a comfortable and safe
manner. Only recently has the U.S.
design guidance suggested on/off ramps for bicyclists to avoid the roundabout
circulating roadway and only then for multi-lane roundabouts. So, the stovepipes developed—roundabouts
serving the needs of cars and in smaller versions the needs of walkers while
cycle track helped bicyclists of all skills move with a high level of safety
between intersections.
Leave it to the Dutch who
experimented with pathways at roundabouts and researching the performance
before and after for treatments to find an avenue where all modes can operate
with increased safety and efficiency at intersections—in a word to resolve the
conflicts between roundabout and cycle track stovepipes. The Dutch research revealed that a roundabout
with a separate bicycle pathway sharply improved safety over alternatives with
or without a bicycle pathway. The
bicyclist community cites research which concludes that a separate path (such
as cycle track) increases bicycle crashes—but that same study shows the
decrease in crashes along street segments provided by the path is overshadowed
by increased crashes at intersections—which, no question—would be signs and
signals. The pathway/bicycle facility
armed roundabout matched with cycle track seems to be the ready resolution of
the dilemma and promises a final erasure of the roundabout and cycle track
stovepipes.
Ideally, the busy
intersection treatment becomes a roundabout with an cycle track approaches on
each leg leading to a separate bicycle pathway more or less in parallel to the
sidewalk system and side-by-side crossings with the walker crosswalk. Of course, not all intersections possess the
space for the ideal of separated bicycle and walker treatment so that multi-use
pathways or—at worst for the cyclist—the on/off ramp (the minimum treatment) on
the sidewalk where, essentially, the bicyclist becomes a walker.
Dutch roundabout
intersection designs now are being circulated as models for bicycle
treatments. And, there is no reason why
research should not confirm the Dutch experience that properly designed
bicyclist treatments at roundabouts along with cycle track along street
segments represent the future for urban street design to the meet the needs of
bicyclists and walkers.
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