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Last Updated: Friday, February 3, 2012 11:30 AM

Exhibit 4.1: Standard Sources of Information

Exhibit 4.1 PDF version here.

Records Review

Cultural resource specialists will typically consult the following sources for projects that require cultural resources studies. Additional research may be appropriate for particularly sensitive regions, such as historic portions of urban areas, mission or pioneer settlements, or locations of historic commercial or industrial facilities (e.g., the Mother Lode gold mining region). Where information is maintained by the Regional Information Centers of the California Historical Resources Information System (CHRIS), cultural resources specialists should specifically request this information as a component of the record search. HRCs are responsible for keeping property listings and determinations of eligibility up to date for their district.

National Register of Historic Places – Current property listings are available through the National Park Service, National Register Program Recent Listings website (updated weekly), or from CHRIS Information Centers. Additionally, all National Register listings are available on-line through the National Register Information System (NRIS) database.

Determinations of Eligibility for the National Register of Historic Places – The Office of Historic Preservation (OHP) maintains this information in its electronic database and distributes hard copies quarterly to the CHRIS Information Centers. For previous determinations on FHWA/Caltrans projects, check the OHP database findings against the SHPO consultation correspondence for that project. The District environmental files and the Division of Environmental Analysis (DEA) files at Headquarters files should both hold copies of these letters.

California Register of Historical Resources – The OHP published the California Inventory of Historical Resources in 1976, and the updates appear in the OHP electronic database. Recent listings appear in the State Historical Resources Commission (SHRC) minutes, available on-line through the OHP website or by contacting the OHP. CHRIS Information Centers also maintain this information. Properties that are nominated to only the California Register are officially listed in the California Register on the date the SHRC approves the nomination, which is the date of the minutes in which the approval appears. The OHP has posted a Historical Resources List that, while not comprehensive, does contain California Register listings, along with National Register, California Historical Landmark, and California Points of Historical Interest listings. It is searchable by county.

California Historical Landmarks – The OHP published the California Historical Landmarks guidebook in 1995. Listings through 1995 are also searchable by county through the OHP website. Subsequent listings appear in the OHP electronic database. Recent listings appear in the SHRC minutes, available on-line through the OHP website or by contacting the OHP. CHRIS Information Centers also maintain this information.

California Points of Historical Interest – The OHP published these listings in 1992; updates appear in the OHP electronic database. Recent listings appear in the SHRC minutes, available on-line through the OHP website or by contacting the OHP. CHRIS Information Centers also maintain this information.

Local Register Listings – Consult city or county government planning departments, historical commissions, or historical societies for current information on locally designated landmarks or resources that are listed under local ordinances or registration programs. Also, OHP’s 1989 Survey of Surveys: A Summary of California’s Historical and Architectural Resource Surveys lists local architectural surveys funded through National Park Service grants through 1989. CHRIS Information Centers maintain this information. HRCs are strongly encouraged to keep updated records of locally designated landmarks for counties and communities in their districts. Many local governments are Certified Local Governments and must have a preservation ordinance in order to be certified. OHP administers this program and maintains a list of contacts for Certified Local Governments on-line.

Archaeological Inventory Files – CHRIS Information Centers maintain this information. The inventory includes site records and reports of survey and excavation projects. A record search should provide identification of previously recorded sites within a one-mile radius of the study area and copies of records for all recorded resources within one-quarter mile.

Caltrans Historic Bridge Inventory – This source is required only when there is a bridge or structure located within the APE. The inventory was updated in 2006; printouts are on file with the Caltrans district environmental branches and include historical ratings for both state and locally owned bridges. See Chapter 7 for information about updates to the inventory. Printouts also are available in the Cultural and Community Studies Office in Headquarters where the original copy is kept.

Background and Property-Specific Research

Secondary Sources

Developing a historical context routinely begins with compiling information on the specific historical themes from secondary sources. Secondary sources are works that analyze or interpret historical information using primary or other secondary sources. They can also provide valuable bibliographical references to primary sources that may be helpful in conducting site-specific research. Occasionally secondary sources may focus specifically on a topic germane to the subject of the research, such as a biography of a former occupant of a house in the APE; a study of a particular industry, such as citrus growing or petroleum development; or a study of a particular event in the history of an area. Secondary sources commonly used in cultural resources studies include:

  • General reference works and local histories: Hoover’s Historic Spots in California, Gudde’s California Place Names, Clark’s Gold Districts of California, Fradkin’s Seven States of California, Starr’s Americans and the California Dream series, the Thompson and West county histories series
  • Ethnographic sources: Volumes 8-11 of the Handbook of North American Indians, Kroeber’s Handbook of the Indians of California, the OHP’s Five Views: An Ethnic Site Survey for California
  • Bibliographic references: Rocq’s California Local History
  • Encyclopedic references: Hart’s Companion to California, Dunlap’s California People
  • Atlases: Beck & Haase’s Historical Atlas of California
  • California Blue Book (annual starting in 1850)
  • Historic Highway Bridges of California (Caltrans, 1990)
  • Historic American Building Survey (HABS), Historic American Engineering Record (HAER) and Historic American Landscapes Survey (HALS) data, available at the Bancroft Library; information can also be accessed through the National Park Service Heritage Documentation website)

Primary Sources

Property-specific research typically involves the use of primary sources. Primary sources (first-hand accounts of historical events or documents produced during the period of significance) can include:

  • Government documents: deeds, mortgages, lease agreements, mining claims, subdivision plats, vital records, census data, permits and licenses, assessor’s parcel information, probate records, Great Register of Voters indexes
  • Serials: contemporary newspapers, periodicals, magazines
  • Diaries, letters, journals, speeches, contemporary interviews
  • Photographs, aerials
  • Oral histories
  • As-built plans
  • Maps: Sanborn Fire Insurance maps, USGS topographic quads, GLO plats and notes, BLM mineral surveys and notes, diseños (post-1850 survey maps of Mexican ranchos)

Local Government Holdings

Many counties and cities maintain official or semi-official archives that can contain a wealth of documents, such as copies of U.S. Census schedules and tax assessment rolls older than ten years. Information such as deeds, grantee/grantor indexes, deeds, and vital records (birth, death and marriage certificates) are kept at the County Recorder’s office. The County Assessor has information on current property ownership; assessor’s plat maps; and appraiser’s records, which often contain construction dates, notes on any moved buildings, and alterations; the Superior Court Clerk’s records contain probate files and information on properties that are subjects of litigation.

Libraries, Historical Societies and Special Collections

Frequently the main library in a city or county seat has a special collection on local history, which holds copies of local newspapers, city or county directories and old telephone books, locally published histories of the community, environmental studies for local planning agencies or special districts, photograph and map collections, etc. In addition, a local historical museum may have a research library or special collection of local historical documents that is available to researchers.

City or county historical societies also may have special historical collections and in many communities, staff from the historical society manages the local archives and museums that maintain research collections. Contacting the local historical society in the initial stages of property-specific research can produce valuable leads for locating important documents and research facilities.

Often local historical society members can identify individuals who may be good candidates for oral history interviews. If an oral history project is recorded on video or audiotape, the tape should be transcribed into printed form if the interview is over five minutes. The oral history is easier to work with in this format and will provide a more durable document for future reference.

College libraries may also have a special collection on the history of the locality or region, or might possess documents on a particular activity (e.g., agriculture of Fresno County) or particular groups or individuals in the region. Usually such collections are held in the main campus library, but often the individual academic departments keep their own libraries or special collections.

The California History Room of the State Library in Sacramento has complete holdings of the census schedules for California, from 1850 to 1930, for every county in the state. It also has a good collection of the Index to the Great Register of Voters from each county, local newspapers, historical maps, city and county directories, and telephone books.

Caltrans Holdings

Caltrans has many primary sources in both Headquarters and in the District offices. The Caltrans Transportation Library and History Center at Headquarters has an extensive collection of research materials covering the history of Caltrans and the development of the state highway system in California, including books; oral histories; article and news clippings; photographs; maps; and Caltrans documents, such as a complete run of the annual reports of the Division of Highways starting from the beginning of the state highway system. Selected photographs and other items in the history collection are accessible to Caltrans staff on the Caltrans Transportation Library and History Center Intranet website. The library also maintains a complete collection of California Highways and Public Works, a valuable source of historical information relating to state highway and bridge projects. Indexes to the journal’s articles and photographs from 1937-1967 are available on-line through the Caltrans DEA website. The library offers a number of services to Caltrans staff statewide, including interlibrary loan and research and reference assistance.

Headquarters has microfilm copies of as-built plans of various contracts completed on state highways from the 1920s to the present together with some diseños and rancho surveys. District offices often have copies of as-built plans as well, including some that are not in Headquarters files. District Right –of Way may also have older plans, maps, and history files. The Division of Structures has as-built plans for bridges and tunnels dating from the 1920s. The Structures Maintenance section has a collection of bridge logs containing inspection records for state highway and local roads bridges. Most of this information is available to Caltrans staff through the BIRIS database on the Structures Maintenance Caltrans Intranet website. Structures Maintenance also retains many final reports from construction projects dating from the 1910s, which are stored off site. Additionally, the state highway bridge log and the local agency bridge log are accessible on-line through the Structures Maintenance website. These contain information on bridge type and whether a bridge has been widened.

As a result of heightened security measures, as-built plans of bridges, tunnels and highway structures are treated as confidential documents. They are great research tools, but it is prudent to avoid using them in documents that will be made public. If their inclusion is necessary in order for FHWA or SHPO to make decisions regarding eligibility or effects, treat them as confidential exhibits that need to be removed from documents that are made available to the public.

National Register Bulletins

Caltrans uses the National Register Bulletin series, published by the National Park Service, to supplement the Environmental Handbook, Volume 2, because the series sets the national standards in how to identify and evaluate cultural resources for using the National Register criteria. In addition, the series offers excellent guidance that can be followed when using the California Register criteria to determine whether a resource is a historical resource under CEQA. The following bulletins are available on-line (some have a series number while others do not; bulletins that are available in print only are not listed):

National Register Bulletin 15: How to Apply the National Register Criteria for Evaluation offers excellent guidance in determining significance and assessing integrity, and it is the backbone of the guidance Caltrans uses when evaluating cultural resources for National Register eligibility.

Other useful National Register Bulletins include:

Caltrans Guidance

Caltrans developed the following historic contexts and guidance for staff to use when encountering ditches and canals and their associated features, as well as for evaluating historic landscapes. The guidance is tailored to resources within California and is also useful for local agency transportation projects.