Inventories and Landmarks

In the early 1980s, the State of Oregon required each jurisdiction to inventory its historic resources. Clackamas County planners did field work and research, compiling 38 binders of the Cultural Resources Inventory, including approximately 3,000 structures. Inventoried properties have basic historical research, photos, and site plans. This inventory has been titled "A Reconnaissance Level Survey Report" by Oregon's State Historic Preservation Office (SHPO). There are no regulatory protections on inventoried properties.

Over about a 10-year span, approximately 300 buildings and structures in the unincorporated areas were further researched, evaluated for architectural and/or historical significance, and designated by the Board of County Commissioners as Clackamas County Historic Landmarks. The cities of Oregon City, Lake Oswego, Canby, West Linn, and the US Forest Service have preservation ordinances that allow them to designate their own historic landmarks. Since 1992, owners have been able to apply to have their historic properties designated as a county historic landmark. See Historic Landmark application.

A property owner must apply to SHPO for a National Register of Historic Places designation. Oregon's SHPO evaluates the nomination, recommends approval to the national level, and regulates National Register Landmarks in Oregon once they are listed. National Register properties automatically become local historic landmarks in most jurisdictions.

How property becomes a local historic landmark

Historic landmark designation may be initiated by the property owner or by a local agency. Historic Landmark applications are available through the Clackamas County Department of Transportation & Development Planning Division and on this website. A pre-application conference with the Historic Resource Planner is required. After review, historic landmark criteria evaluation, and public hearing, the Historic Review Board recommends whether to approve the historic landmark designation. The Board of County Commissioners make the final decision to apply a Historic Overlay Zone that enacts Historic Preservation Section 707 of the Clackamas County Zoning Ordinance. In Oregon, an "owner consent" provision requires the property owner to request or approve designation. Once a property has been designated, all alterations or additions to the exterior of the building require Historic Review Board approval. The Historic Overlay Zoning may offer more potential uses of the property and, when available, may make it eligible for restoration funding. More specific information is in Historic Preservation Section 707 of the Clackamas County Zoning Ordinance.

A commemorative "Clackamas County Historic Landmark" plaque is also available for the property owner for purchase to be placed on the building's exterior.

If you feel your Clackamas County property has historic merit, please contact Linda Preisz in the Planning Division at 503-742-4528. She will set up a pre-application meeting to assist you in preparing the information needed to submit an application.

Clackamas County Historic Landmark Ordinance

As stated in Section 707 of the Clackamas County Zoning Ordinance, the purpose of the Historic Overlay Zone is to implement the goals and policies of the County's Comprehensive Plan and promote public health, safety, and general welfare by safeguarding the County's heritage as embodied and reflected in its historic resources. The provisions of the ordinance are intended to:

  • Provide for the identification, protection, enhancement and use of sites, structures, corridors, objects and buildings within the County that reflect special elements of the County's architectural, archeological, artistic, cultural, engineering, aesthetic, historical, political, social, and other heritage;
  • Facilitate restoration and upkeep of historic buildings, structures, and other physical objects or geographical areas;
  • Encourage public knowledge, understanding, and appreciation of the County's history and culture;
  • Foster community and neighborhood pride and sense of identity based on recognition and use of cultural resources;
  • Promote the enjoyment and use of historic and cultural resources;
  • Preserve diverse architectural styles reflecting phases of the County's history and encourage complementary design and construction impacting cultural resources;
  • Enhance property values and increase economic and financial benefits to the County and its inhabitants;
  • Identify and resolve conflicts between the preservation of cultural resources and alternative land uses; and
  • Integrate the management of cultural resources and relevant data into public and private land management and development processes.

What makes a structure historic?

As stated in Section 707 of the Clackamas County Zoning Ordinance, a site, structure, or object may be zoned Historic Landmark if it is listed on the National Register of Historic Places or if it is rated as "significant" using the County's procedure for evaluating historic resources under the specific architectural, environmental, and historic association criteria. A site or structure must receive 40 or more points under the following criteria to be considered for Historic Landmark status:

Architectural significance

  • It is an early (50 years or older) or exceptional example of a particular architectural style, building type, or convention.
  • It possesses a high quality of composition, detailing, and craftsmanship.
  • It is a good, or early, example of a particular material or method of construction.
  • It retains, with little or no changes, its original design features, materials, and character.
  • It is the only remaining, or one of the few remaining, properties of a particular style, building type, design, material, or method of construction.
  • A Guide to Historic Building Types and Architectural Styles in Clackamas County

Environmental significance

  • It is a conspicuous visual landmark in the neighborhood or community.
  • It is well-located considering the current land use surrounding the property, which contributes to the integrity of the pertinent historic period.
  • It consists of a grouping of interrelated elements including historic structures, plant materials and landscapes, viewsheds and natural features.
  • It is an important or critical element in establishing or contributing to the continuity or character of the street, neighborhood, or community.

Historical significance

  • It is associated with the life or activities of a person, group, organization, or institution that has made a significant contribution to the community, state, or nation.
  • It is associated with an event that has made a significant contribution to the community, state, or nation.
  • It is associated with, and illustrative of, broad patterns of cultural, social, political, economic, or industrial history in the community, state, or nation.
  • It possesses the potential for providing information of a prehistoric or historic nature.
  • Example: Barlow Road

Requirements for Historic Landmark property

Historic Landmark property is subject to the standard building and zoning code requirements. Demolition, lot-line changes, and relocation require County Planning staff review. If a project requires a building permit, generally the Historic Review Board must review and approve exterior alterations to existing buildings or new construction on the property based on Historic Preservation Section 707 of the Clackamas County Zoning Ordinance. A Historic Overlay Zone often enables a wider variety of uses for the property than is allowed in the underlying zoning.