The siting of wind facilities to minimize visual impacts to high-value scenic resources presents a
major challenge for land management agencies in the western United States. The visibility and
potential visual contrasts associated with utility-scale wind facilities are dependent on complex
interactions of a variety of factors, but little systematic study of visibility in real landscape
settings has been conducted.
In a study sponsored by the United States Department of the Interior Bureau of Land
Management, 377 observations of five wind facilities in Wyoming and Colorado were made
under various lighting and weather conditions. The facilities were found to be visible to the
unaided eye at >58 km (36 mi) under optimal viewing conditions, with turbine blade movement
often visible at 39 km (24 mi).
Under favorable viewing conditions, the wind facilities were judged to be major foci of visual
attention at up to 19 km (12 mi) and likely to be noticed by casual observers at >37 km (23 mi).
A conservative interpretation suggests that for such facilities, an appropriate radius for visual
impact analyses would be 48 km (30 mi), that the facilities would be unlikely to be missed by
casual observers at up to 32 km (20 mi), and that the facilities could be major sources of visual
contrast at up to 16 km (10 mi).
Robert G. Sullivan
Program Manager/Coordinator, Environmental Science Division, Argonne National Laboratory, Argonne, Illinois
Leslie B. Kirchler
Landscape Specialist, Environmental Science Division, Argonne National Laboratory
State Landscape Architect (retired), Wyoming State Office, U.S. Department of the Interior, Bureau of Land Management
NLCS Wilderness Program Lead and Visual Resource Program Lead, Wyoming State Office, U.S. Department of the Interior, Bureau of Land Management
Programmer Analyst, Environmental Science Division, Argonne National Laboratory
Senior GIS Programmer/Analyst, Environmental Science Division, Argonne National Laboratory
Programmer/Analyst, Environmental Science Division, Argonne National Laboratory
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