March
6, 2001
Jeff
Morales, Director
California Department of Transportation
P.O. Box 942873
Sacramento, CA 94273-0001
Dear
Mr. Morales:
I request that you perform an independent review of the position taken by
the Engineering Service Center on the acceptability of the Wyoming Rail
for use in California. On October 6, 2000, you wrote to Sara Wan, Chair
of the Coastal Commission: “Caltrans is committed to exploring all
viable options to satisfy the Coastal Commission’s need for a
‘see-through barrier rail’ for use on designated scenic routes.” (Emphasis
added.)
The Engineering Service Center of Caltrans has steadfastly refused to
approve the Wyoming Rail as originally designed and successfully crash
tested. In so doing, it is denying the Commission and the California
public the best scenic railing that meets current safety standards.
There is a substantial history underlying the Service Center’s current
rejection of the Wyoming Rail. I am separately making a Public Records
Act request to create a public record of this history. The results of
this request will help you in your independent review. Please use your
offices to direct that my request be fulfilled expeditiously.
To assist you in your review, I am enclosing copies of selected
correspondence and documents related to the safety acceptability of the
Wyoming Rail and its use in California.
As explained below, the Engineering Center's refusal to accept the Wyoming
does not conform to prevailing professional methodology for determining
the safety of bridge railings. Additionally, I learned recently that
in 1992 Caltrans approved and began using a Wyoming Rail design in
California. Yet, despite all of the focus on the Wyoming Rail in
Commission proceedings on the Noyo Bridge and in the deliberations about
scenic rails, Caltrans has never given the Commission the slightest
indication that it has previously approved and used a version of the
Wyoming Rail. This omission raises serious questions that need to be
answered.
The Engineering Center's current rejection of the Wyoming Rail will not
withstand an impartial independent review for the following reasons:
·
The
latest "safety standard" asserted by the Engineering Center for rejecting
the Wyoming Rail is not considered relevant to judging the safety
performance of bridge railings by any nationally recognized safety
authority.
·
Crash-test results as specified in NCHRP Report 350 are considered by all
nationally recognized safety authorities as the sole determinant of
the safety performance of bridge railings. The latest version of the
Wyoming Rail has achieved a safety performance (Test Level 4, or TL-4)
equal to or better than all of the other scenic rails being proposed to
the Commission by Caltrans.
Further, Caltrans needs to explain why it has never told the Coastal
Commission that in 1992 it approved and began using a Wyoming Rail design
in California.
Consider each of the
above in more depth.
Caltrans latest
“safety standard” is not relevant to safety; crash tests are the sole
determinant of railing safety performance
In December 2000, the Engineering Service Center of Caltrans admitted that
the Wyoming Rail met the AASHTO LRFD geometric design standards. These
were the standards that it originally said the Wyoming Rail did not meet,
thus justifying its radical modification of the crash-tested design of the
Wyoming Railing. But, at the very same time it made this admission, it
created a new "safety standard" to justify its modification of the Wyoming
Rail.[i]
This “safety standard” was an extension of a geometric design guide
contained in Appendix A of the LRFD standards. It is to be emphasized that
the AASHTO LRFD Standards do not contain the requirement imposed by
Caltrans.
There is no support
for Caltrans’s latest "safety standard" in any national safety-standard
organization or specification.
The American Association of State Highway Transportation Organizations
(AASHTO), the Federal Highway Administration (FHWA), and the National
Cooperative Highway Research Program (NCHRP) unanimously assert that the
only determinant of the safety rating of a railing is its
performance in crash tests. Geometric design criteria, such as the one now
being asserted by Caltrans, are explicitly rejected as determinants of
railing safety performance – for the very good reason that crash tests
have shown them to be poor predictors of safety performance.[ii]
The assertion of geometric design criteria to reject the safety-tested
Wyoming Rail by a professional engineering organization (Caltrans) is
particularly puzzling. AASHTO standards in existence since the 1980’s
have allowed highway departments to use a railing that had passed crash
tests even if did not meet static loading and geometric design criteria.[iii]
As noted above, the safety community has now completely rejected geometric
design standards for judging railing safety, mandating that crash tests be
used to determine railing safety all applications.
The irrelevance of the latest Caltrans geometric-design "safety standard"
to safety performance is illustrated by Caltrans own experience with its
Type 80 railing, one of the railings it proposes as a “scenic railing.”
The first version of the Type 80 railing conformed to the latest
Caltrans "safety standard," but failed its crash test. Based on this
result, Caltrans modified the design and crash tested it again. The
modified design when combined with a sidewalk (the Type 80SW) still failed
to pass the Test-Level 3 (TL-3) crash test. As a result, the Type 80SW
was only conditionally accepted by the FHWA and by Caltrans for use
where a TL-2 performance is acceptable (traffic speeds less than 45 miles
per hour). Thus, Caltrans own approval process recognizes that
crash-test results are the final determinant of the safety performance of
a railing.
Caltrans has proposed using the Type 80SW on the Noyo Bridge replacement.
The TL-4 Wyoming Rail is indisputably safer than the TL-2 Type 80SW.
Wyoming Rail
Previously Approved for Use in California
The story of the prior approval of a Wyoming Rail design is particularly
poignant because it was the outcome of a negotiation with many parallels
to the present one between the Commission and Caltrans. The earlier
negotiation took in the early 1990's between Caltrans and the Tahoe
Regional Planning Agency (TRPA). TRPA is a congressionally mandated
bi-state (Nevada/California) agency that is organized to maintain and
enhance the scenic and aesthetic qualities of the Lake Tahoe region. The
negotiation was over the railing to be used on a 0.7 mile stretch of State
Route 89 along Emerald Bay near Cascade Lake and Eagle Falls on the
southwestern shore of Lake Tahoe. Construction on the project began in
April 1992.
The publication "Flexibility in Highway Design," published by the FHWA in
1997, summarizes the negotiation and its results:
Although the original
barrier design proposed by Caltrans was the generally accepted statewide
standard for such applications, it was considered to be unacceptable by
the TRPA. The two-beam guardrail which was finally installed had been
crash tested by the FHWA some years earlier but had not, at the time of
this project, been adopted by Caltrans as an acceptable guardrail type.
Subsequent to the project, the two-beam guardrail design was accepted by
Caltrans as a standard design, particularly in areas with similar
aesthetic considerations.[iv]
The photo on the left below shows the railing that Caltrans installed at
Emerald Bay. The one on the right is a Wyoming Rail (TL-3 version) near
Yellowstone Park.

Caltrans Rail on
Emerald Bay, Rte 89 |

Wyoming Rail
near Yellowstone |
These photos confirm
that the railing approved by Caltrans for the Emerald Bay Project is
the earlier (Test-Level 3) Wyoming Rail. Thus, in 1992 Caltrans
approved the Wyoming Rail for use in California. This rail was used in
many places in California before its use was discontinued.
The Test-Level 3 Wyoming Rail is still accepted by the FHWA for general
use on the National Highway System. When and why did Caltrans "decertify"
its California version of the Wyoming Rail, leaving the state with no good
aesthetic railing to use in scenic areas? I hope you will obtain an
answer to this question.
The need for a review of Caltrans policy on scenic railings
National and state design standards give Caltrans wide latitude to
accommodate special situations. Preserving scenic values is widely
recognized as an important reason to use this flexibility. In passing the
Intermodal Surface Transportation Efficiency Act (ISTEA) of 1991, Congress
emphasized, in addition to safety, the importance of transportation design
that is sensitive to its surrounding environment, especially in historic
and scenic areas.[v]
In the case of scenic railings, Caltrans could fulfill the public’s desire
for the most visually transparent scenic railing without compromising
safety in any way. Instead the Engineering Service Center has rigidly
opposed its approval.
I urge you to perform an independent review of the basis on which the
Engineering Service Center has denied approval of the Wyoming Rail and to
provide the results to the Coastal Commission. I hope that you will then
follow up this review by developing a policy guide that directs your
department to make transportation design sensitive to its surrounding
environment, especially in historic and scenic areas.
Sincerely,
Vince Taylor
Executive Director
Encl.: Selected correspondence and documents related to the Wyoming Rail
cc: (w/o enclosure) Sara Wan, Peter Douglas, Chris Desser, Shirley
Dettloff, Senator Wes Chesbro, Assemblywoman Virginia Strom-Martin

[i]
This “safety standard” arbitrarily requires that that the “opacity
ratio” of a railing be higher than that of any of the
successfully crash-tested railings used to draw Figure A1.1.1-3 of the
AASHTO LRFD Standards. The opacity ratio measures the percentage of
the railing height that is covered by railing surfaces. The higher
the opacity ratio, the less will be the view through the rail.
Requiring a high opacity ratio, as Caltrans is doing, rules out all
visually transparent railings – regardless of their tested safety
performance. It is to be emphasized that the AASHTO LRFD Standards
do not contain the requirement imposed by Caltrans.
[ii]
The history of the rejection of geometric and static design criteria
was summarized by J. W. Hatton of the Federal Highway Association:
Until the late 1980’s designers
relied on precedent, …AASHTO “Standard Specifications for Highway
Bridges,” and their judgment to design a bridge railing for a
particular site. The Standard Specifications, as they still do,
called for the application of a 10-Kip static load … as well as some
dimensional requirements for the openings between rail elements and
other cross section geometry [geometric design criteria]. Full-scale
crash testing was not required, although a design that “passed”
crash testing could be used even if it did not meet the static loading
and/or geometric design criteria. [Emphasis added]
In the late 1970’s and early 1980’s,
actual tests were run on several commonly-used railings that had been
designed under the static loading procedures. The results were
unexpected: several of the railings failed quite dramatically and it
was shown that static design loadings were not sufficient to ensure
adequate railing performance. As a result of these findings, … [the
FHWA] issued a policy memorandum on August 28, 1986, that stated that
railings on bridges on Federal-aid projects must be (or have been)
crash tested and meet the acceptance criteria in NCHRP Report 230 or
equivalent procedures.
J. W.
Hatton, Bridge Railing Design and Testing, a Discussion with the
AASHTO Highway Subcommittee on Bridges and Structures, Technical
Committee (T-7) for Guardrail and Bridge Rail, May 14, 1996.
[iv]
Flexibility in Highway Design, Federal Highway Administration,
Publication Number FHWA-PD-97-062.