Sierra Club Conservation Policies
(1) Air tours are flights conducted for sightseeing.
(2) The Sierra Club supports management tools and methods to diminish or eliminate
impacts from aircraft tours and landings, including bans of tours and landings wherever
and whenever appropriate, on National Monuments and units of the National Park System and
the National Wilderness Preservation System.
(3) Agencies should preserve and, where there are impacts, fully restore the natural
quiet within protected areas and address this issue in their general management plans.
(a) The Sierra Club believes that, to be the most appropriate and effective, control
over air tour use of airspace above such protected areas should rest with the respective
land management agencies (e.g., National Park Service, U. S. Forest Service, Bureau of
Land Management, U. S. Fish and Wildlife Service). These are the agencies in position to
understand these areas most intimately, and which are charged to provide them the fullest
possible resource protection.
(b) The managing agency should work with responsible parties to reduce or eliminate air
tours or landings outside a protected area if needed to restore natural quiet within the
unit. Federal managers of adjoining areas should coordinate their management planning
(c) The Sierra Club supports the establishment of appropriate noise standards and
comprehensive baseline sound-level monitoring and sound-source inventories of all
protected areas. This includes continual assessment of noise from all human-generated
sources and incorporation of public comments about noise impacts.
Background: Principles of Natural Quiet
(1) The sounds and silences of nature are among the intrinsic elements that combine to
form the natural environment. Natural sounds amidst intervals of stillness are inherent
components of the "scenery and the natural and historic objects and the
wildlife" within National Monuments and units of the National Park System and
National Wilderness Preservation System.
(2) Natural quiet is the extended opportunity to experience only natural sounds amid
periods of deepest silence. The quiet to be preserved or restored is as defined by the
National Park Service as "the quiet at the lower end of the ambient sound level range
that occurs regularly between wind gusts, animal sounds, etc., not just the average sound
level." As the Park Service explains, "Lulls in the wind or interludes between
animal sounds create intervals where the quiet of a sylvan setting is quite striking. In
considering natural quiet as a resource, the ability to hear clearly the delicate and
quieter intermittent sounds of nature, the ability to experience interludes of extreme
quiet for their own sake, and the opportunity to do so for extended periods of time [are]
what natural quiet is all about."
(3) Many of these protected areas are vast, open places of astonishing beauty and
wildness. Each protected area has a distinct and powerful aura, fully dependent upon the
tenuous natural sounds and natural quiet. As such, these areas afford unique opportunities
for undistracted respite, solitude, contemplative recreation, inspiration, and education.
Further, these units also provide scarce refuge and undisturbed natural habitat for
animals. Artificial, human-generated noise can disturb some sensitive animal activities.
Therefore, noisy overflights that disturb the peace are not normally appropriate in our
Quotations are from National Park Service, U.S. Department of Interior, Report
to Congress on Effects of Aircraft Overflights, 1994.
Adopted by the Sierra Club Board of Directors, February 17th, 2001.
See also these other conservation policies: Transportation, Noise Pollution, Military Airspace.