home *** CD-ROM | disk | FTP | other *** search
- Path: sparky!uunet!paladin.american.edu!darwin.sura.net!spool.mu.edu!agate!darkstar.UCSC.EDU!karplus
- From: karplus@cse.ucsc.edu (Kevin Karplus)
- Newsgroups: rec.bicycles.soc
- Subject: Re: Safety and Bikeways
- Date: 22 Dec 1992 00:59:44 GMT
- Organization: University of California, Santa Cruz (CE/CIS Boards)
- Lines: 66
- Distribution: world
- Message-ID: <1h5pa0INN4g8@darkstar.UCSC.EDU>
- NNTP-Posting-Host: ararat.ucsc.edu
-
- John Forester says
-
- The design of bikeways is intended to reduce the 1.9% of the
- 18% (equals 0.3%) of accidents to cyclists that are caused by
- motorists hitting lawful cyclists from behind while overtaking
- them.
-
- I believe that there are some other accident types that some bikeway
- designs address---in particular a bike lane that is made by removing
- on-street parking. Of course, it is the removal of the parked cars,
- not the painting of the bike lane stripe that provides the extra
- safety.
-
- Removing the parked cars eliminates nthe collisions with parked cars,
- and reduces accidents due to cars or bike pulling out of driveways,
- since visibility is substantially impeded by on-street parking.
-
- Thus, to John's 0.3%, I would add
- Collision with parked car (4%)
- Driveway exit (1%) about 1/2 the driveway exit accidents
- (excluding wrong-way or sidewalk)
-
- Thus the accident reduction expected is more like 5% than .3%.
- Of course, this analysis ignores the main problems with bike lanes:
- that they encourage wrong-way riding, left-turns from the right curb,
- and motorists turning right in front of bikes. Adding even small
- increases in those types of accidents swamps even my more optimistic
- estimate of the possible gains from putting in bike lanes.
- And so, I reluctantly agree with John, that bike lanes are probably
- not a safety improvement.
-
- (Why reluctantly? Because bike lanes are the best mechanism I've
- found for getting sufficiently wide right hand lanes and parking
- elimination---both of which are substantial improvements to the road.
- If we could get those improvements without the lane stripes, I'd be
- happier, but it is hard to convince traffic engineers, politicians,
- and other bicycle advocates of the value of such invisible improvements.)
-
- One problem with John's figures (not his fault) is that Ken Cross's
- study is rather old. The number of adult bicyclists has increased
- considerably since 1976 (or whenever Ken Cross's study was done).
- Infact, I believe that 1991 was the first year in which adult bicyclist
- fatalities exceeded child bicyclist fatalities. It isn't clear that
- the many modern adult bicyclists are as good as the few adults that
- were riding in 1976, and so the accident causes may have shifted.
- Probably an even larger percentage of adult accidents are
- cyclist-caused than in Cross's study.
-
- I agree with John that better education would help enormously, but I
- don't see the infrastructure to do it. There is no mechanism in this
- country for educating adult bicyclists (the LAW program is miniscule,
- and is mainly preaching to the choir, not reaching those who need it
- most). Even bicycle education for children (who are a captive
- audience) is almost non-existant. The modern material (videos, books,
- ...) for bicycle education is better than the "bike safety" material
- from the 50s, but there are few teachers who know enought to teach the
- material, and no interest by the State in funding bike education.
-
-
- Kevin Karplus
- Effective Cycling Instructor
- --
- Kevin Karplus karplus@ce.ucsc.edu
-
- Due to budgetary constraints the light at the end of the tunnel is
- being turned off.
-