The best and most reliable way to determine if a building or structure is greater than 50 years in age (constructed after 1955), is to check the tax records for the property. However, you can also estimate the age of a structure by interviewing the current resident of the structure, a local historian or others who are familiar with the structure. Often the date of construction is posted somewhere on or in the property, especially for public buildings or structures. If you believe the project will affect a building or structure constructed during the 1950s, verify the actual date of construction using tax records.
To determine if your project will affect a building or structure 50 years or older in age, you need to consider the direct and indirect impacts that your project may have. Direct impacts refer to work on or in a building or structure 50 years old or older that could result in an alteration to the character, or diminish the integrity of the property. Examples of this include: retrofitting or replacing historic bridges; elevating, relocating, or retrofitting historic buildings; and acquiring and demolishing historic buildings. If your project application proposes any work that will directly modify a building or structure older than 50 years in age, including demolition, you must provide additional documentation in the comments area of Section A of the PDM Environmental and Historic Preservation Questions.
Indirect impacts are project impacts that affect nearby historic properties, and are typically limited to the introduction or removal of elements into the existing visual landscape. The term “close proximity” (defined with examples below) can vary in distance depending on the project type and location, and refers to a geographical area around your project site. For the purposes of your PDM application, a structure is in “close proximity” to your project if it is visible from your project site. If there are any buildings or structures 50 years old or older visible from your project site, you should document the date and location of these structures in your PDM application. If several buildings or structures 50 years old or older are visible from your project site, you should make an extra effort to determine if they are part of a larger historic district that may not be visible from your project site.
Examples of Projects in Close Proximity
A project involves replacing dual 24-inch diameter concrete reinforced pipe culverts with a single 60-inch diameter corrugated metal culvert. To do this, the roadway approach on either side of the culvert will have to be elevated 4 feet, causing a slight elevation in the roadway. This project will change the nature of the surrounding landscape – there will be a hump in the road now and some additional signage warning motorists of the hump. The area of close proximity for this project includes both the area from which the project is visible, and all areas visible from the project site. In this example, the area of close proximity may only be 200 to 400 feet from the proposed culvert.
A project involves replacing 20 wooden power poles with 16 concrete power poles along a one-mile section of road. The existing wooden poles rise 45 feet from the ground, whereas the proposed poles would rise 70 feet from the ground. This project has changed the surrounding landscape by introducing 16 new elements into the skyline. The area of close proximity for this project includes both the area from which the project is visible, and all areas visible from the project site. In this example, close proximity may be all areas within 2,000 feet of any single tower.
A project involves installing hurricane shutters on four stories of a modern building. The area of close proximity for this project includes the surrounding buildings from which the project is visible, including any adjacent buildings built before 1955.