Guidelines for Preserving Cultural Landscapes
Identifying, retaining and preserving existing topography. Documenting topographic variation prior to project work, including shape, slope, elevation, aspect, and contour. For example, preparing a topographic survey.
Evaluating and understanding the evolution of a landscape’s topography over time. Using archival resources such as plans and aerial photographs or, in their absence, archeological analysis techniques, to understand the historic topography.
Executing project work that impacts topography without undertaking a topographic survey.
Executing project work without understanding its impact on historic topographic resources, such as watershed systems.
Stabilizing and protecting topography in a manner that is appropriate to the character of the landform. For example, installing a temporary protective textile over an eroding slope or restricting access to fragile earthworks.
Allowing unstable topographic conditions to deteriorate without intervention. For example, permitting pedestrian access to further degrade threatened landforms.
Maintaining historic topography by use of non-destructive methods and daily, seasonal, and cyclical tasks. This may include cleaning drainage systems, mowing vegetative cover or managing groundhogs.
Failing to undertake preventive maintenance.
Utilizing maintenance methods which destroy or degrade topography, such as using heavily weighted equipment on steep or vulnerable slopes.
Repair declining topographic features. For example, re-excavating a silted swale through appropriate regrading or re-establishing an eroding terrace.
Destroying the shape, slope, elevation aspect, or contour of topography when repair is possible.
Utilizing a replacement material that does not match the historic material when the historic material is available. For example, using asphaltic materials to fill in natural sink holes in a turfed or soil area.
Replacing in-kind topographic features where there is extensive deterioration and damage. For example, minor filling and soil rejuvenation in areas of subsidence.