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Dharma Cloud Foundation
PO Box 1066
Mendocino, CA  95460


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.

[iii] Ibid.

[iv] Flexibility in Highway Design, Federal Highway Administration, Publication Number FHWA-PD-97-062.

[v] Ibid.