BIKE PATH:   SAFE?
Presentation by Roger Becker at the Sharing Chappy Roads Forum
Tuesday, August 11th, 2009

Rest assured, we are all looking for the same thing- SAFE BICYCLING ON CHAPPAQUIDDICK.

Bike paths play an important and needed function when we need to move traffic.

But, there is overwhelming evidence that tells us that while bike paths are effective at moving traffic, they are not safer for bicyclists,  --  the pedestrians they hit,  --  nor the cars that hit them.

You should know that building a two way shared use side path is not going to add any safety to the Chappaquiddick  Road system, but rather it will add more intersections and conflicts between bicycles, pedestrians and motor vehicles. 

It would be like building a second road on Chappaquiddick.

The State of Massachusetts says that Shared Use Paths are facilities on an exclusive (that is :  not shared) right of way with minimal cross flow by motor vehicles.  The American Association of State Highway and Transportation Officials’ Green Book lists 9 problems with paths located adjacent to roadways.        I think most of you know the problems of side bike paths because there are many along the roads of Martha’s Vineyard.          Have you ever had any conflicts with path users at Al’s package store?  Or going to the post office?  Actually, there have been many accidents right in Edgartown because of the flawed concept of putting a mini road right next to the main road. 

This is a safety problem we don’t need on Chappaquiddick.   

SHOW GRAPHIC of intersection conflict.  (From Wauchtel Lewiston study).

http://www.wright.edu/~jeffrey.hiles/essays/listening/ch7.html

And this is only one problem with these paths out of nine mentioned in the guide.  

Dr Colvin points to the Moritz study of 1996 which shows that people who commute regularly on bike paths rather than the road are safer on bike paths by 33% but that same study shows those commuters are 5 times more likely to crash while using a SIDE walk.  

But, I will quickly mention 7 studies from the US and Europe that show the risks of using this type of bike path.  Studies like these are the reason the state does not recommend shared use paths within road right of ways where there are intersections with the cross flow of motor vehicles.   

Zehnfenning, 1993, Palo Alto, CA.  Finding?  Streets with side paths carried 15% of bicycle traffic but accounted for 70% of the motor vehicle/bicycle accidents.

Wauchtel Lewiston, Palo Alto, CA, 1985-89---Bicyclists crossing intersections from side bike paths were nearly twice as likely to collide with cars than bicyclists crossing intersections while riding on the street.

From the Helsinki traffic planning division,  Dr. Eero Pasanen, states “ It’s safer to cycle in streets with cars rather than on 2 way bike paths which run parallel to streets. 45% of the cycling distance is traveled on paths along the streets, but 56% of injury accidents happen to these cyclists.

The University of Lund, Sweden shows that if you are traveling straight through an intersection on a bike path you have a 3 1/2 times greater crash risk than if you were to bicycle on a road amongst the cars through that same intersection.  If you are on a bike path that runs parallel to the road, but bicycling in the opposite direction of the nearest car lane,  your risk is nearly 12 times that of the cyclist who rides on the road in the correct lane with the cars traveling the same direction.  

No wonder the AASHTO design guide understates “when two way shared use paths are located immediately adjacent to a roadway, some operational problems are likely to occur.”

In a Denmark study looking at 40 miles of side paths over three years,  bicycle crashes increased at junctions from 71 per year before the paths were built to 105 after the bike paths  were built.  That’s a 50% increase, yet bicycle use remained constant.  

In a summary of many bicycle studies, done by Clark and Tracy, in 1995, for the Dept of Transportation, they point to Clark and Bruckner who studied bicycling across Europe. That study shows increases of crashes on side walk bike paths. Larson, studying Sweden, Norway and Finland where Bike side paths are common, shows clear increases in intersection accidents with these kinds of paths.

There’s another safety aspect which may literally have an impact on you personally if you choose to continue biking on the road after a bike path is built on Chappy.  Without a change in enforcement levels, speeds on the road will increase if drivers perceive they are not in danger of coming across a pedestrian or cyclist on the road.  What is the effect of that?

LET ME SHOW YOU.  (Graphic from 1995 Oregon bicycle and pedestrian plan). 

The Sharing Chappy Roads committee, just like you, is interested in promoting BIKE SAFETY on Chappaquiddick. 

There is overwhelming evidence that tells us that  Two – Way  Side  Bike  Paths  are VERY effective at allowing cars to speed along.   But they ARE more dangerous. 

Adding a  road to Chappaquiddick won’t make anyone any safer. 

LETS SHARE THE ONES WE HAVE!