May 1, 2001

Chris Desser
Shirley Dettloff
Bridge Rail Subcommittee
California Coastal Commission
45 Fremont Ave, Suite 2000
San Francisco, CA  94105-2219
Fax: (415) 904-5400

Dear Commissioners:

I was delighted to receive a copy of the letter from Rich Land to you in which he enclosed a photo of the proposed California ST-10 Railing (April 10, 2001).  This railing appears to be based on the Wyoming TL-4 railing and has much the same degree of visual transparency.  I commend Caltrans for its willingness to present the Commissioners and the California public with this superior alternative.

The California ST-10, as shown, is a wonderful starting point for developing a scenic railing.  I have additional points to make about this railing and its use in different applications: 

1.      I can’t tell from the photo if the vertical posts are solid or are composed of two parallel steel plates as in the Wyoming rail.  Use of steel plates as opposed to solid posts makes the railing visually more transparent and “lighter,” both desirable attributes of a scenic railing. The Wyoming Rail has been safety tested and there is no safety question about their use of parallel steel plates for the posts.  If the ST-10 does not use parallel plates, I suggest that you recommend to Caltrans that this be done.



2.      For use on scenic bridges with sidewalks, the preferred visual solution is a two-rail system, which I described fully to you and other Commissioners on December 13, 2000.[i]  The ST-10 would form the inner (traffic-side) rail, replacing the CA Type 2 rail in the photo on the left.  Please request Caltrans to commit to this configuration for bridges with sidewalks.

3.      The Commission should begin to focus on modifications of the basic rail to meet pedestrian and bicycle safety:

a.      Pedestrian Safety 

·        For bridges with sidewalks, the two-rail system is strongly preferred.

·        For bridges that need pedestrian protection but don’t have sidewalks (will this happen in practice?), the basic ST-10 will need an additional horizontal rail to bring the total height up to 42 inches.  Request Caltrans to provide the Commission with alternative designs that incorporate a pedestrian rail.

·        The least visually disruptive way to meet the minimum openings for pedestrian safety within the horizontal steel rails is to use thin metal cables, as is done in the proposed bicycle barrier for the Golden Gate Bridge.  Request Caltrans to provide the Commission with a design that incorporates steel cables to provide pedestrian safety with the ST-10.

 

b.      Bicycle Safety:  Apparently AASHTO Standards will require all bridges on Highway 1, which is a designated bicycle route to have a railing height of 54 inches.  If this is required, the railings will be much more visually obtrusive than if a lower railing is used. A rail at 54 inches is also a visual barrier for bicyclists and opposed by some bicycle groups.   The 54” height is currently the subject of controversy from a number of parties involved with designing new bridges in scenic areas.

The material provided to me by Caltrans in response to a public record act request suggests that AASHTO may have misinterpreted human-body center-of-gravity information in setting the 54-inch height.  The Commission should request Caltrans to work with state bicycle groups to further analyze the physics of bicycle safety and to develop tests that will determine what is required to provide bicycle safety.  The results of these tests can then be brought to AASHTO to develop a more valid standard for bicycle safety.  I believe that such empirical testing will show that a lower railing height, perhaps the pedestrian standard of “42”, will suffice.  This result would simplify railing inventory for Caltrans and provide more visually appealing railings for the public.

4.      The Noyo Bridge Railing: If Caltrans begins construction of the Noyo Bridge this summer, the Commission must resolve details of its railing design quickly.  Based on my long study of this bridge and it scenic vistas, I recommend the following:

a.      Use of a two-rail system for the Noyo Bridge, with a traditional spoke railing for the outside of the bridge.  The outer rail should be painted the same green as the existing railing to provide a degree of continuity in appearance.

b.       The sidewalk should be at the same level as the traffic deck of the bridge.  The curb of the ST-10 will provide protection from rain runoff onto the sidewalk.  As compared to a raised sidewalk, a flush sidewalk will lower the outer edge of the bridge by 6 inches.  Although this may seem small, it translates into many feet of additional downward view into the harbor for motorists.  The added width of the new bridge, its wide pedestrian shoulders and sidewalk will greatly impair the downward view into the harbor, preventing motorists from viewing the harbor waters.  Everything should be done to provide as much downward view as possible.

c.      Find out from Caltrans if the ST-10 can be used as the inner (traffic-side) rail without modification for pedestrian protection.  Given that the current design has no inner rail at all, the ST-10 unmodified would provide significantly greater pedestrian protection.  Also point out to Caltrans that there is an 8-foot safety lane outside of the sidewalk, so pedestrians who went over or through the rail would not land in a traffic lane.

If the rail must be modified to provide pedestrian protection, please have Caltrans provide you with the specific standards that require this modification of the ST-10.  Note that this modification would significantly impact the aesthetics of the overall railing.  Note also that the bridge photo on page 1 of this letter has an inner rail that is not modified for pedestrian protection.

5.      Use of the Wyoming Rail as an interim scenic rail: If crash testing of the ST-10 is required (it might not be if it is substantially a Wyoming Rail with minor modifications), and it is required to fix on a scenic rail for a bridge soon to be constructed, Caltrans should use the Wyoming Rail on an exception basis.  This rail meets all current safety standards, releasing Caltrans from tort liability concerns. The parts to construct this rail would be readily available.  It meets the aesthetic and visual concerns of the Commission. 

Thank you for the opportunity you have provided to work with you to achieve a scenic railing of which everyone can be proud.  We are approaching achievement of this goal.  Let us take the last steps as carefully as the first.

Sincerely,

Vince Taylor

CC: Steve Scholl, Peter Douglas, Sara Wan