Order Code RS22025
Updated January 13, 2006
CRS Report for Congress
Received through the CRS Web
Wilderness Laws:
Permitted and Prohibited Uses
Ross W. Gorte
Specialist in Natural Resources Policy
Resources, Science, and Industry Division
Summary
The Wilderness Act generally prohibits commercial activities, motorized uses, and
infrastructure developments in congressionally designated wilderness areas. However,
the Wilderness Act and many subsequent laws designating wilderness areas also contain
provisions authorizing activities that do not conform with these general prohibitions.
The general prohibitions and the authorized uses are important, because controversies
persist over permissible and prohibited activities in wilderness areas, and because bills
often seek to modify existing areas or activities. This report will be revised periodically.
Congress approved the Wilderness Act (P.L. 88-577; 16 U.S.C. §§1131-1136) in
1964 to establish a National Wilderness Preservation System on federal lands “where the
earth and its community of life are untrammeled by man, where man himself is a visitor
who does not remain.” As of December 31, 2005, the System totals 683 units, with 106.3
million acres. (See CRS Report RL31447, Wilderness: Overview and Statistics, by Ross
W. Gorte.) Congress has taken two basic approaches to protecting the wilderness
attributes on certain federal lands while allowing some uses that might alter the pristine
character of the lands. One approach, described here, is to explicitly allow uses in
congressionally designated wilderness areas that do not conform with the Wilderness
Act’s general management guidance; the other, not covered in this report, is to designate
areas by some other label, with special management direction for those areas in the laws
creating them.
The Wilderness Act, directly and by cross-reference in many subsequent wilderness
statutes, generally prohibits commercial activities, motorized uses, and roads, structures,
and facilities in units of the National Wilderness Preservation System designated by acts
of Congress. Specifically, §4(c) states:
Except as specifically provided for in this Act, and subject to existing private
rights, there shall be no commercial enterprise and no permanent road within any
wilderness area designated by this Act and, except as necessary to meet minimum
requirements for the administration of the area for the purpose of this Act (including
measures required in emergencies involving the health and safety of persons within
the area), there shall be no temporary road, no use of motor vehicles, motorized
Congressional Research Service ˜ The Library of Congress

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equipment or motorboats, no landing of aircraft, no other form of mechanical
transport, and no structure or installation within any such area.
This section thus prohibits most businesses and commercial resource exploitation
(such as timber harvesting) and motorized or mechanical entry (via cars, trucks, off-road
or all-terrain vehicles, bicycles, aircraft, or motorboats) except in emergencies.
Wilderness Act Provisions
The Wilderness Act also authorizes activities that do not conform with the general
restrictions, usually subject to regulation by the Secretary.1 Specifically:
! §4(d)(1) allows “the use of aircraft or motorboats, where these uses have
already become established,” subject to “desirable” restrictions;
! §4(d)(1) also allows “such measures ... as may be necessary in the control
of fire, insects, and diseases,” subject to “desirable” conditions;
! §4(d)(2) allows mineral prospecting conducted “in a manner compatible
with the preservation of the wilderness environment”;
! §4(d)(3) provides for establishing and developing valid mineral rights,
“subject, however, to such reasonable regulations governing ingress and
egress as may be prescribed” consistent with using the land for mineral
development, and with leases, permits, and licenses containing “such
stipulations as may be prescribed ... for the protection of the wilderness
character of the land consistent with the use of the land...”;
! §4(d)(4) allows the President to authorize water project development,
including road construction and use;
! §4(d)(4) also allows livestock grazing, “where established prior to the
effective date of this Act ... subject to such reasonable regulations as are
deemed necessary”; and
! §4(d)(6) allows commercial services “which are proper for realizing the
recreational or other wilderness purposes of the areas.”
In addition, access for livestock and wildlife management have fostered concerns
over the years. After discussions in several Congresses, the 101st Congress provided
detailed guidelines in H.Rept. 101-405, the Interior and Insular Affairs Committee’s
report on the Arizona Desert Wilderness Act of 1990 (P.L. 101-628). Appendix A (pages
41-43) is “Grazing Guidelines,” and states (among other provisions):
The maintenance of supporting facilities, existing in an area prior to its
classification as wilderness (including fences, line cabins, water wells and lines, stock
tanks, etc.), is permissible in wilderness. Where practical alternatives do not exist,
maintenance or other activities may be accomplished through the occasional use of
motorized equipment.... Such motorized equipment uses will normally be permitted
in those portions of a wilderness area where they had occurred prior to the area’s
designation as wilderness or are established by prior agreement.
1 The Wilderness Act generally referred to the Secretary of Agriculture, because the act initially
only designated wilderness areas in the National Forest System. Subsequent wilderness laws
refer to the Secretary of Agriculture or Secretary of the Interior, depending on who has
jurisdiction over the designated areas.

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The construction of new improvements or replacement of deteriorated facilities
in wilderness is permissible if in accordance with these guidelines and management
plans governing the area involved....
The use of motorized equipment for emergency purposes such as rescuing sick
animals or the placement of feed in emergency situations is also permissible.
Appendix B of H.Rept. 101-405 (pages 44-51) is “Wildlife Management Guidelines.” It
provides guidance similar to the grazing guidelines in Appendix A of H.Rept. 101-405,
and reads in part:
This language [§4(c) of the Wilderness Act] is viewed as direction that all
management activities within wilderness be done without motor vehicles, motorized
equipment, or mechanical transport, unless truly necessary to administer the area or
are specifically permitted by other provisions in the Act. It means that any such use
should be rare and temporary; that no roads can be built; and that wilderness managers
must determine such use is the minimum necessary to accomplish the task. Any use
of motorized equipment or mechanical transport requires advance approval by the
administering agency....
Flow-maintenance dams, water developments, water diversion devices, ditches
and associated structures, and other fish and wildlife habitat developments necessary
for fish and wildlife management (which were in existence before wilderness
designation) may be permitted to remain in operation.
Appendix B provides additional direction and examples of authorized activities for
various specific fish and wildlife management activities, including population surveys and
sampling, fish stocking, wildlife transplanting, and more.
These appendices to H.Rept. 101-405 have been referenced in many subsequent
wilderness statutes as relevant guidance for administering grazing and wildlife in the
designated wilderness areas.
Subsequently Enacted Provisions
In addition to the special provisions in the Wilderness Act that allow otherwise-
prohibited activities in some circumstances, many subsequent laws designating units of
the National Wilderness Preservation System have authorized specific uses or activities
that do not conform with the general prohibitions on access to and use of wilderness areas.
Typically these provisions apply to one or a few areas, although occasionally the
provisions apply to all the areas designated in the statute. These provisions are identified
below, grouped into several categories and arranged chronologically from the earliest
enactment within each category.
Motorized Access — Land.
! P.L. 95-237, Endangered American Wilderness Act of 1978: §2(i) allows
local government access for maintaining current and future watershed
facilities in one unit in Utah.
! P.L. 95-249, Absaroka-Beartooth Wilderness Act: §4 preserves a right-
of-way claim in one unit being litigated at that time.
! P.L. 95-495, Boundary Waters Canoe Area Wilderness Act: §4(e) allows
snowmobile use in certain units; §4(d) and §4(g) allow mechanized

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portages in certain units; §4(h) allows continued motorized uses only;
and §4(i) allows motorized access for emergencies and administrative
purposes.
! P.L. 96-487, Alaska National Interest Lands Conservation Act of 1980:
§703(b) allows mechanized portage equipment in a specific unit.
! P.L. 96-560, Colorado Wilderness Act of 1980: §102(a)(17) allows
motorized access for maintenance of water resource facilities in one unit.
! P.L. 98-425, California Wilderness Act of 1984: §101(a)(2) and (25)
allow continued access for livestock facilities in two specific units;
§101(a)(6) allows motorized administrative use of a fire road between
contiguous wilderness units; and §101(a)(24) allows a right-of-way for
construction.
! P.L. 98-428, Utah Wilderness Act of 1984: §302(b) allows access for
local government to maintain current and future watershed facilities in 9
of the 12 wilderness units designated.
! P.L. 98-550, Wyoming Wilderness Act of 1984: §201(a)(11) allows
motorized federal access for bighorn sheep management in one
designated unit.
! P.L. 101-628, Arizona Desert Wilderness Act of 1990: §101(a)(3) allows
access for operating and maintaining a pipeline in one unit; §101(a)(20)
provides access and use of a powerline right-of-way in one unit; and
§101(k) allows continued use and maintenance of a particular road.
! P.L. 102-301, Los Padres Condor Range and River Protection Act:
§2(5) allows continued use of a road corridor in one unit until a bypass
is completed.
! P.L. 103-77, Colorado Wilderness Act of 1993: §8(d) allows motorized
access for use, operation, maintenance, repair, and replacement of water
resource facilities in existence upon enactment in all designated units.
! P.L. 103-433, California Desert Protection Act of 1994: §102(1) and
(13) provide rights-of-way for military access across two designated
units; §103(f) allows state motorized access for wildlife management;
and §708 guarantees access to nonfederal lands within all designated
units.
! P.L. 106-456, Spanish Peaks Wilderness Act of 2000: §3(a) allows
continued historic uses of the Bulls Eye Mine Road.
Motorized Access — Water.
! P.L. 93-429, Okefenokee National Wildlife Refuge Wilderness Act: §2(1)
allows powered watercraft of 10 horsepower or less within the unit.
! P.L. 95-495, Boundary Waters Canoe Area Wilderness Act: §4(c)
identifies horsepower limits and duration (some access is temporary) for
motorboats in specific counties and/or lakes within the unit; and §4(f)
limits motorboat use to historic levels, except for homeowners.
! P.L. 98-430, Florida Wilderness Act of 1984: §1(4) allows continued
motorboat use in one unit.

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Motorized Access — Air.
! P.L. 95-237, Endangered American Wilderness Act of 1978: §2(i) allows
helicopter access for sanitary facilities in one unit in Utah.
! P.L. 96-312, Central Idaho Wilderness Act of 1980: §7(a)(1) allows
continued landing of aircraft within a designated unit.
! P.L. 98-428, Utah Wilderness Act of 1984: §302(b) allows helicopter
access for sanitary facilities in 10 of the 12 designated units.
Water Infrastructure.
! P.L. 95-237, Endangered American Wilderness Act of 1978: §2(e)
protects rights for water diversion and use, including operations,
maintenance, repair, and replacement of water project facilities in one
unit in Colorado.
! P.L. 96-550, New Mexico Wilderness Act of 1980: §102(a)(9) retains
existing management, rules, and regulations for a municipal watershed
in one unit.
! P.L. 96-560, Colorado Wilderness Act of 1980: §102(a)(5) protects
rights for water diversion and use, including operation, construction,
maintenance, and repair of water project facilities in one unit.
! P.L. 98-425, California Wilderness Act of 1984: §101(a)(25) protects
rights for water diversion and use, including construction, operation,
maintenance, and repair of water project facilities in one unit.
! P.L. 98-550, Wyoming Wilderness Act of 1984: §201(c) protects rights
for water diversion and use, including construction, operation,
maintenance, and modification of water project facilities in four units.
! P.L. 101-628, Arizona Desert Wilderness Act of 1990: §101(l) protects
flood control dam operations in one unit; and §301(e) and §302 direct
that the two units abutting the Colorado River shall have no effect on
upstream dams or on water management in the Upper Colorado River
Basin, respectively.
! P.L. 103-77, Colorado Wilderness Act of 1993: §2(a)(13) protects rights
for water diversion and use, including construction, operation, use,
maintenance, and repair of water project facilities in one unit.
! P.L. 103-433, California Desert Protection Act of 1994: §202 and §203
direct that the two units abutting the Colorado River shall have no effect
on upstream dams or on water management in the Upper Colorado River
Basin, respectively.
! P.L. 107-282, Clark County Conservation of Public Land and Natural
Resources Act of 2002: §208(d) authorizes structures and facilities for
wildlife water development projects, if the Secretary of the Interior
determines they will enhance wilderness values and if the visual impacts
“can reasonably be minimized.”
! P.L. 107-370, Big Sur Wilderness and Conservation Act of 2002: §8
authorizes construction and maintenance of a new water line and
corresponding spring box adjacent to an existing domestic water service
in one unit.

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Other Infrastructure and Activities.
! P.L. 95-237, Endangered American Wilderness Act of 1978: §2(c) and
§2(d) allow fire prevention and watershed protection activities in two
units.
! P.L. 96-312, Central Idaho Wilderness Act of 1980: §5(d)(1) allows
prospecting and exploration for and development of cobalt within part of
one unit.
! P.L. 96-550, New Mexico Wilderness Act of 1980: §102(a)(5) allows
construction of additional fencing for livestock grazing in one unit.
! P.L. 97-384, Charles C. Deam Wilderness Act: §3 allows access to and
maintenance of a cemetery in one unit in Indiana.
! P.L. 98-322, Vermont Wilderness Act of 1984: §104(c) allows
maintenance of trails and associated facilities in all designated units.
! P.L. 98-406, Arizona Wilderness Act of 1984: §101(a)(13) allows
installation and maintenance of hydrological, meteorological, and
telecommunication equipment in one unit.
! P.L. 98-428, Utah Wilderness Act of 1984: §305 allows installation and
maintenance of hydrological, meteorological, climatological, and
communication equipment in 9 of 12 designated units.
! P.L. 100-668, Washington Park Wilderness Act of 1988: §102 allows the
maintenance, repair, and replacement of an underground powerline
through one unit.
! P.L. 101-195, Nevada Wilderness Act of 1990: §10 allows installation
and maintenance of hydrological, meteorological, and climatological
equipment in all designated units.
! P.L. 101-628, Arizona Desert Wilderness Act of 1990: §301(g) allows
continued border operations within one designated unit.
! P.L. 101-633, Illinois Wilderness Act of 1990: §9 allows access to and
maintenance of a cemetery in one unit.
! P.L. 102-301, Los Padres Condor Range and River Protection Act:
§3(b) allows fire prevention and watershed protection activities in one
unit.
! P.L. 103-433, California Desert Protection Act of 1994: §103(g) allows
motorized law enforcement activities within all designated units; and
§705(a) provides for Native American access for cultural and religious
purposes.
! P.L. 106-156, Dugger Mountain Wilderness Act of 1999: §2(d) allows
motorized use of a road for two years to disassemble and remove a fire
tower that was scheduled for removal, with the road permanently closed
thereafter.