CALTRANS HISTORIC BRIDGES INVENTORY UPDATE: TIMBER TRUSS, CONCRETE TRUSS, AND SUSPENSION BRIDGES PREPARED F"DR: STATE CF' CALIF'DRNIA DEPARTMENT CF' TRANSPDRTATIDN ENVIRONMENTAL PROGRAM 1 1 20 N STREET SACRAMENTO, CALIF'DRNIA 95B 14 PREPARED BY: JRP HISTORICAL CONSULTING 1490 DREW AVENUE, SUITE 1 1 0 DAVIS, CALIFORNIA 9 56 1 6 APRIL 2004 Cover Images: (Top to bottom, left to right) Bridge 04C0048, Zane’s Ranch Road over Elk River, Humboldt County; Bridge 53C0996, Vasquez Canyon Road over Bouquet Creek, Los Angeles County; Bridge 02C0049, Canyon Creek Road over Scott River, Siskiyou County; Bridge 47C0012, Cunningham Lane over West Walker River, Mono County; Bridge 42C0551Z, Elkhorn Road over Murphy Slough, Fresno County; Background Detail from Original Plans, Bridge Near Zanes on Branch Route No. 32 Over Elk River, 1936, Courtesy of the Humboldt County Public Works Department. For individuals with sensory disabilities this document is available in alternate formats. Please call or write to Andrew Hope, Caltrans Environmental Program, Mail Station 27, P.O. Box 942874, Sacramento, CA, 94274-0001. (916) 654-5611 Voice, or use the CA Relay Service TTY number 1-800- 735-2929. Caltrans Historic Bridge Inventory Update: Timber Truss, Concrete Truss, and Suspension Bridges Contract: 43A0089 Task Order: 01 EA: 43-984433 Prepared for: State of California Department of Transportation Environmental Program 1120 N Street Sacramento, California 95814 Prepared by: Christopher McMorris JRP Historical Consulting 1490 Drew Avenue, Suite 110 Davis, California 95616 April 2004 SUMMARY OF FINDINGS JRP Historical Consulting (JRP) prepared this report for the State of California Department of Transportation (Caltrans) Environmental Program at Caltrans Headquarters in Sacramento, as part of the department’s program to update its historic bridge inventory. Caltrans intends to use this report to request concurrence from the State Historic Preservation Officer (Office of Historic Preservation, OHP) on the National Register eligibility of 25 timber truss, concrete truss, and suspension bridges built in California prior to 1960. These determinations will be used to assist the Federal Highway Administration (FHWA) and Caltrans in compliance with environmental and historic preservation laws and regulations as these pertain to historic properties. The historic bridge inventory update will, most importantly, help in compliance with Section 106 of the National Historic Preservation Act and the California Environmental Quality Act (CEQA). Caltrans completed its initial historic bridge inventory in 1986. The original inventory included the survey of all known examples of timber truss, concrete truss, and suspension bridges with an emphasis on evaluating structures constructed prior to 1936. The timber truss bridges were part of the original truss survey, including both metal and timber structures, and the concrete truss and suspension bridges were part of the original survey that included all bridge types other than trusses. Caltrans began updating it historic bridge inventory in 2002. Caltrans architectural historians and its consultants prepared the various components of the inventory. The inventory included preparation of a historic overview covering the period 1936 to 1959, which was not addressed in the initial bridge survey. Fieldwork and evaluations of bridges were divided by bridge type. For the concrete arch and metal truss, moveable, and steel arch portions of the update inventory, Caltrans decided to continue use of the numeric point rating system that had been developed for the initial bridge survey. For other types of bridges, including timber trusses, concrete trusses, and suspension bridges, Caltrans elected to utilize standard qualitative evaluation techniques given that the survey populations of these types were small and did not require the statistical qualitative numeric system useful for the larger survey population. Accordingly, JRP inventoried and evaluated sixteen timber truss bridges, four concrete truss bridges, and five suspension bridges built before 1960. JRP prepared DPR 523 forms for the eighteen structures that were not previously determined eligible or already listed in the National Register of Historic Places. JRP field checked the other seven structures in the survey i population that were previously determined eligible for or listed in the National Register. JRP assessed the significance and historic integrity of each previously eligible or listed bridge and included a discussion of continued eligibility in this report. This document is divided into sections that provide information on the inventory and evaluation update process as well as historical background. The project description section provides information on the initial Caltrans bridge inventory and details on the current survey. This is followed by a description of the field and research methods used during this survey. Next is an historical overview that provides the historic themes and context by which appropriate evaluations can be made of the survey population. This is followed by a description of the survey population and the findings and conclusions of this study. The final component provides the preparer’s qualifications and a list of works cited. Appendix A includes letters received from the interested public during the public participation process, Appendix B has map figures, and Appendix C contains DPR 523 Primary Record and Building, Object, and Structure forms for the eighteen bridges evaluated/re-evaluated. Appendix D has photographs of bridges previously found eligible or listed in the National Register. Figure 1 (Appendix B) illustrates the counties in which this survey was conducted and the total number of timber truss, concrete truss, and suspension bridges inventoried in each county. Figure 2 (Appendix B) provides a set of regional maps of California, based on Caltrans Districts, showing the location of each bridge. The DPR 523 forms in Appendix C provide descriptions and photographs of each bridge, location data, and historic evaluation information. Of the 25 bridges studied for this report, the seven structures previously listed or determined eligible for listing in the National Register retain historic integrity and retain their current National Register status, and the remaining eighteen structures do not appear to meet the criteria for listing in the National Register. The seven eligible or listed structures include the four concrete trusses in the survey population, two of the five suspension bridges, and one of the sixteen timber truss bridges. These seven structures are considered historical resources for the purposes of CEQA. All of the timber trusses, except for the Oregon Creek covered bridge, and three of the suspension bridges do not appear to be eligible for National Register listing, and are not considered historical resources for the purposes of CEQA. ii TABLE OF CONTENTS Summary of Findings ………………………………………………………………………….. i 1. Project Description – Historic Bridge Inventory Update ………………………………….. 1 1.1. Background ………………………………………………………………………….. 1 1.2. Current Project ………………………………………………………………………. 2 2. Field and Research Methods ……………………………………………………………… 5 2.1. Compilation of Information and Research …………………………………………... 5 2.2. Fieldwork ……………………………………………………………………………. 5 2.3. Public Participation ………………………………………………………………….. 6 3. Historical Overview ………………………………………………………………………. 7 3.1. Important Events and Trends in Transportation Development ……………………… 7 3.1.1. County Era: 1880 to 1909 ……………………………………………………... 9 3.1.2. Early State Era: 1910 to 1929 …………………………………………………. 9 3.1.3. Depression Era: 1930 to 1940 ………………………………………………… 10 3.1.4. World War II Era: 1941 to 1946 ……………………………………………… 14 3.1.5. Postwar Period: 1947 to 1959 ………………………………………………… 16 3.2. Engineering, Design, and Construction …………………………………………….. 19 3.2.1. Timber Trusses ……………………………………………………………….. 19 3.2.2. Suspension Bridges …………………………………………………………… 26 3.2.3. Concrete Trusses ……………………………………………………………… 28 3.2.4. Engineers, Designers, and Builders …………………………………………… 31 4. Description of the Survey Population ……………………………………………………. 35 4.1. Timber Trusses ……………………………………………………………………… 36 4.2. Suspension Bridges …………………………………………………………………. 37 4.3. Concrete Trusses …………………………………………………………………….. 39 5. Findings and Conclusions ………………………………………………………………... 41 5.1. Evaluation Criteria ………………………………………………………………….. 41 5.2. Bridges in Historic Districts and Historic Landscapes …………………………….. 43 5.3. Eligibility for Listing in the National Register of Historic Places …………………. 44 5.3.1. Bridges previously listed or determined eligible for the National Register ….. 46 5.3.2. Bridges that do not appear to meet the criteria for National Register listing … 47 6. Preparers’ Qualifications ………………………………………………………………… 55 7. Bibliography …………………………………………………………………………….. 57 TABLES Table 1: Number of Bridges from Periods of Construction …………………………………. 35 Table 2: Truss or Construction Types ……………………………………………………….. 37 Table 3: Bridges previously listed or determined eligible …………………………………… 46 Table 4: Bridges that do not appear eligible for listing in the National Register ……………. 47 PHOTOGRAPHS Photograph 1: Cattle Canyon Creek Bridge (53C0972) …………………………………….. 12 Photograph 2: Cayucos Creek Bridge (49C0248). A-Frame truss built in 1940 …………… 22 Photograph 3: Gleason Canyon Bridge (53C1021). Howe pony truss constructed in 1956 ... 23 Photograph 4: Berta’s Ranch Road Br. (04C0047). Howe truss covered bridge built