Vehicle Intrusions

Informational boundary signs are an important tool in defending wilderness boundaries. Boundary signing should be strategized according to the setting. A wilderness boundary nearby lands where uses incompatible with wilderness occur (e.g. an off-highway vehicle area) may need closely placed signs. On the other side of the spectrum, a rugged and remote wilderness boundary well removed from areas of incompatible use may need no boundary signs at all.

Signs have two functions: 1) they inform visitors of the boundary to help foster compliance; and, 2) they provide notification (such as by displaying regulations) upon which law enforcement officers can cite violators. There are many forms of these signs within two categories: 1) kiosks or decorative signs placed at major wilderness access points (such as along trails); and, 2) general demarcation signs that are placed at regular intervals along the boundary. In all cases, consider positive and enforcement messages: include a welcoming message to visitors while at the same time providing necessary regulatory messages necessary for law enforcement.

See BLM example: Wilderness and WSA Decals

Informational boundary signs can and should be installed along wilderness boundaries prior to cadastral surveys. Informational boundary signs placed along boundary roads do not need survey precision to notify vehicle users and enforce boundaries as vehicle incursions tend to be gross violations where such precision is immaterial.

Boundary signs will require monitoring and maintenance.

A fiberglass sign post is durable, but is vulnerable to being laid down with a rock. After the rock is removed the sign appears functional (until the next time a rock is laid on it). Consider using a different post type in this location or installing a fence post to back up the sign, but install a second fencepost nest to it so that the presence of a fencepost is visible.

Ensure agency maps are available to depict wilderness boundaries. However, recognize that the agency is not the only map provider. Readily share accurate boundary information with all map providers as soon as possible after wilderness designation.

Note that with a new designation you should not wait for legal descriptions to be prepared before sharing data. It is better to provide the best information available to the public as soon as possible. A legislative map with a boundary line that may be adjusted later to correct errors in accuracy is better than not having a publicly available map. Provide a disclaimer on boundary accuracy in the legend.

Provide outreach to visitors and communities to help them understand appropriate uses of wilderness and create community buy-in. Describe Public Lands as a spectrum of resources, values and benefits, with wilderness filling a specific niche. Don’t just talk about wilderness, but also identify the continued availability of non-wilderness opportunities (for example, a nearby high-quality motorized trail).

Consider producing websites, information packets, fact sheets, brochures, and kiosks or informational signs at key areas. Many user groups and communities will incorporate this same information into their own maps and materials if you make it readily available to them.

Outreach is critical to improve the effectiveness of all other methods of preventing vehicle incursions. Work with partners, motorized and non-motorized user groups, vehicle manufacturers and suppliers, outfitters, guides, and local communities to communicate wilderness values and designations.

An important way to prevent use of unauthorized vehicle routes in wilderness is to make them disappear. A tried and effective method in making old vehicle routes disappear is transplanting native vegetation into the old routes to camouflage them; in essence creating a visual barrier. This technique is especially useful in more arid environments where dispersed low vegetation exists, as physical barriers in these places tend to be ineffective (drivers can easily drive around a barrier). If visitors are unable to discern the route they won’t drive on it. When repeated impact of vehicles ceases, vegetation is often able to reclaim the site within a few years without the need for more intensive restoration efforts. Sources of vegetation for the visual barrier are typically from the sides of open roads around the wilderness (sourcing vegetation from road edges creates very little impact). Even if the vegetation dies during transplanting, it often looks enough like the surrounding vegetation for enough time that drivers don’t discern it as a road, don’t drive on it, and natural seed dispersal and germination reclaims the site.

Transplanted vegetation (even if dead) helps to provide shade and retain soil moisture and provides texture in which naturally blown in seeds can germinate. If the site is also first prepped with picks to break up soil compaction and create small divots, this can help for better moisture retention and seed germination and facilitate recolonization of the site by native vegetation.

This technique can be done in conjunction with physical barriers and signing, but in many cases it’s better to not install barriers or signs because they can give away the site and attract unwanted continued use of the old route.

This approach is feasible to implement using hand tools, is cost effective, and the techniques can be quickly learned by novices, making it possible for this work to be taken on by volunteers. Development of this approach is supported by research and testing of intensive restoration including planting live nurserygrown native vegetation. It was observed that even when nursery-grown vegetation died, it still tends to prevent motor vehicle use. The approach of transplanting roadside vegetation that would likely die in the process could be quicker, less of an impact on wilderness character, and more cost effective than intensive restoration with nursey-grown plants. A meticulous attempt to mimic the appearance of the surrounding vegetation in texture, density, and variety, as well as incorporating rocks that blend with the surrounding geology and landscape in the same manner, further contribute to success.

Before and after of a reclamation site. Note the wilderness boundary sign is not a “road closed” sign. Every site is different, even placing this sign may be enough to attract attention, and so think through your strategy case by case. In this case it may be better to place the sign 50 feet away.

Before and after of a reclaimed vehicle route. Note the route closed sign has been removed to avoid attracting attention.

Note:

• Information about large restoration efforts is located at the end of this section.
• See the Ecological Intervention and Site Restoration Toolbox and the Small Scale Restoration section for more detailed information.
  

Conversion of what was formally a vehicle route to a non-motorized trail can be an effective method to preventing vehicle use of the route. Some wilderness enabling laws even include statutory requirements to develop a trail plan which would include considering such conversion. However, trails are an installation, and installations are prohibited unless they are the minimum necessary for the purpose of the Wilderness Act, that is to preserve wilderness character. Though trails are easily overlooked as a “normal” component to wilderness, conversion of a vehicle route to a non-motorized trail needs to be consistent with preserving wilderness character and should be screened through the following considerations:

• Is the route sustainable or is it causing unacceptable impacts to other resources? For example, if the route is causing unacceptable impacts to culture resources, is impacting a population of rare plants or is concentrating human use at limited water sources critical to wildlife, the route should be considered for removal and restoration. However, if the impact is limited, a short reroute to correct the problem may be appropriate.
• Does the route support a non-motorized recreational purpose? A route readily useable by foot or horseback visitors to access sites of interest or one that travels through the landscape in a way sought out for primitive recreation may be appropriate to manage as a trail. Motor vehicle hill climbs or routes that access past mineral exploration sites are examples of routes unlikely to provide for primitive recreation and should be removed.
• How does the route affect wilderness character, specifically the five tangible qualities: natural, untrammeled, undeveloped, opportunities for solitude or primitive and unconfined recreation, and other features of value? The route should be considered within the context of preserving wilderness as a whole, by considering all positive and negative impacts to each quality.
• Would the route be sustainable as a trail? Many former vehicle routes are steep, capture the flow of water, or traverse the landscape in ways that may cause excessive impacts without extensive ongoing maintenance. Modification or relocation of a portion of such a route may be sufficient to correct the problem. The need for extensive rerouting, however, should flag the route for closure and reclamation. There is no bright line between minor and extensive relocation; each situation will be uniquely considered in a Minimum Requirement Analysis.
• A former vehicle route converted to a non-motorized trail may produce better results for wilderness preservation than simple closure. A route that is closed may be likely to be trespassed on, while conversion to a trail used by hikers and horseback riders may be less comfortable for a motor vehicle operator to drive as they would be rebuked or reported by non-motorized visitors.
• Some pre-existing routes (motorized or non-motorized) may not be suitable for management as a system trail, but may also not be realistically closed and rehabilitated. These may remain open for use though they are not managed as a part of the trail system (not placed on visitor maps and visitors are not directed to them by other means). For example, a steep route to the top of a peak, or a route into a canyon in which solitude is being safeguarded. Visitors may continue to use these trails, but the trials would only receive monitoring and limited maintenance to prevent unacceptable resource impact.
• A new vehicle route established after wilderness designation is a trespass which needs to be restored and should not be converted into a trail.

Fence tied into slope and vegetation coupled with a walk through (visible on the far side) turning the old vehicle route into a trail.

Site of old road, converted into trail where fill and culvert were removed. The road was converted to a hiking trail and new trail tread through restoration area was constructed.

These barriers prevent motor vehicles while allowing for hikers and horse packers to pass. It is important to leave enough space so that a wheelchair can also pass.

If the decision is made to repurpose an old vehicle route to a hiking and horseback riding trail, it is important to also present it as a trail by providing trailhead parking defined with barriers, signs and kiosk as appropriate, and take measures to reduce the trail to a single tread.
Note:

• See the Signs and Kiosks Toolbox for more detailed information.
  

It is important to couple law enforcement presence with physical work toward preventing vehicle intrusions. Include in budgets regular patrols, overtime, and specialized equipment. Work with law enforcement officers to prioritize patrols, gain their input to project implementation, and get their buy-in. However, the geographic range of many of the agency’s law enforcement officers is huge, and so reliance on law enforcement to prevent vehicle intrusions is unlikely to solve vehicle incursion issues. Law enforcement officers cannot cover all areas thoroughly, so identify areas of particular vulnerability and with repeated intrusions, and focus law enforcement attention there.

Physical barriers or gates are not feasible and effective at all wilderness incursion areas. For example, in open landscapes they can be driven around. They can also be expensive to install and maintain and the subject of vandalism. In places where authorized vehicle use must continue, a locked gate is the only option. Physical barriers may include large boulders, large ditches (often called tank traps), or berms. To be effective, physical barriers and gates must be tied into the surrounding topography and or vegetation, and should be outside the wilderness boundary. Often, providing visitors advance notice that a road will end ahead puts visitors into the right state of mind before reaching the barrier, and improves compliance. Be strategic using physical barriers, limiting them to where the most active motor vehicle incursions exist. Also incorporate site design to allow for accessibility (barriers may need to provide a specific width of passage for mobility impaired users).

This physical barrier includes a sign which provides information on alternative legal off-highway sites.

An aptly placed metal post in concrete may be more successful than a fiberglass sign post that can be easily laid over with a rock.

Gates should only be used where there is authorized vehicle access, such as to a private inholding. Where there is authorized vehicle access, gates must be installed, as such access routes are not open to the general public. The positioning of this gate to tie into the adjacent slope and vegetation greatly improves its effectiveness.

Some routes existing prior to wilderness designation were constructed, include large road features, may be in a soil type that is not conducive to natural restoration, or may have other conditions which require a more intensive restoration approach than the visual barrier technique described above. The MRA process is essential in considering these situations. For example, where a large cut and fill road exists, the land may first need to be recontoured to assure it does not significantly disrupt the hydrology of the site or present a long-term sediment source harmful to aquatic ecosystems. In addition, pre-existing culverts should be removed because without maintenance culverts can become plugged causing the old road to become a dam, and eventually will blow out. This can cause considerable damage downstream by scouring and contributing high amounts of sediment to streams. See the Ecological Intervention and Site Restoration Toolbox and the Small-Scale Restoration section for more detailed information.

Culvert removal on what was once a constructed and maintained road, but is now a wilderness area.

In some soil types, eliminating vehicle use will not naturally result in vegetation return due to loss of top soil, water flow, or soil compaction. Extensive management intervention may be necessary to break up soil compaction, prevent water from moving down the route, or other actions to slow water and provide seed germination sites.

Vehicles have not been driven on this route for many years because of a physical barrier placed below. However, revegetation has not occurred due to soil compaction and runoff capture.

After motorized equipment work, soils are no longer compacted and surface texture was created to slow water movement and improve infiltration. This treatment creates safe sites for plant seed to germinate, improves soil moisture availability for germinating seeds, and allows plant roots to penetrate.

Breaking up soil compaction with heavy equipment on what was once a constructed and maintained road may be necessary to reclaim some sites.

In some cases, a route may also serve excepted purposes; such as access to a valid occupancy or authorized facility (e.g. radio repeater or livestock facility). In these cases, a gate as described in the preceding tab may be warranted. However, note that a route to a facility may still be closed and rehabilitated where irregular motor vehicle access is necessary. Facility maintenance may be provided by cross-country means in an alternate location. For example, a livestock reservoir may only need to be cleaned out every ten years. Keeping a vehicle route open to be used once every ten years, all the while attracting unauthorized use during that time period, would have a greater impact on the wilderness than a once-every-ten-year pass of a backhoe cross country. These situations are terrain-dependent and must be considered and determined through a Minimum Requirement Analysis on a case-by-case basis.

Summary

• A broad overall strategy to vehicle intrusion is essential. Applying several techniques is more likely to be successful than a single approach.
• Plausible strategies should be evaluated in a minimum requirements analysis to find the one that will provide the most benefits and least degradation to wilderness character.
• Success generally involves recurring tasks; for example, education, replacing signs, redoing/renewing a restoration treatment, community engagement, or maintaining a law enforcement presence. Expect to have a long-term commitment to preventing vehicle incursions.
• Everything can’t be done at once; preplan your strategy and task implementation. Take actions that are quickest, least costly, and reasonably sufficient first. For example, place signs first and install gates later.
• It is essential to monitor to determine effectiveness and improve wilderness protection. Monitoring will help you determine the optimal mix of techniques to apply to specific situations.

General: Because this type of transportation is non-motorized, it is often misunderstood as allowable in wilderness. In actuality, these type of aircraft are prohibited from takeoff and landing in wilderness. These activities are often described by proponents as compatible with wilderness because there is little to no impact to soil and vegetation – especially in comparison to impacts from other forms of recreation. However, impact to wilderness character is not limited to soil and vegetation impact - as with other recreational activities, impacts to solitude is an area of concern.

Definitions: Is the use of a wingsuit considered “aircraft,” and thus prohibited by the Wilderness Act? Yes, a wingsuit meets the definition of aircraft in 14 CFR 1.1 as a device used for flight (see above definition). Consider the Wikipedia description of wingsuit flight: “Wingsuit flying (or wingsuiting) is the sport of skydiving using a webbing-sleeved jumpsuit called a wingsuit to add wetted area to the diver’s body and generate increased lift, which allows extended air time by gliding flight rather than just free falling.”

Monitoring: Mostly this activity is monitored in the field. However, also look for videos and web posts to identify if this activity is beginning in the wilderness you manage.

• Example Video:
  • Paria Canyon – Vermillion Cliffs Wilderness
• mention the option for staff to follow up with the video host/creator to educate them or take enforcement action against subjects depicted?

Communication: Include information on websites and brochures for wilderness areas where there are attractive features or areas for this type of activity. Paraglider pilots seek steep open grassy slopes with good exposure to steady breezes. Wingsuit pilots seek tall open cliffs. Hang glider take-off in wilderness would be unusual because of the weight of the aircraft that must be carried in, but a boundary road near a high open ridge may be desirable to hang glider pilots. Consider providing information for wilderness areas with these characteristics.

Related uses: Participants to these activities might also utilize motorized transport to access launch zones or for retrieval once landed.

Resources: This article makes several mistakes including not recognizing that numerous NPS and BLM federal land areas are designated as wilderness where aircraft landing is prohibited under Section 4(c) of the Wilderness Act. However, the article helps to provide awareness for the topic.

• Deaths renew calls for national parks to rescind BASE jumping bans

General: Drones are prohibited from landing and take-off in wilderness as are all other aircraft. In addition, because they are also motorized equipment, operating a drone from within wilderness is prohibited – in other words, where the takeoff and landing occurs outside of wilderness but the operator is controlling the aircraft from within wilderness. A mere flight over wilderness when the controller is also outside the wilderness is not prohibited simply because the area is wilderness, though it is discouraged because of the impact it can have on wilderness character (e.g. visitors solitude and wildlife) and because it runs counter to the FAA’s advisory for aircraft to remain at least 2,000 feet above ground level when flying over wilderness. Agency staff considering agency-operated drone overflight of wilderness should consider the impact of such use before engaging in it (see your agency policy for analysis requirements).

Definitions: Popularly known as drones and formally described as Unmanned Aircraft Systems (UAS), they do not carry a human operator and normally carry a payload, the payload often being a camera or specialized sensors to collect data.

Monitoring: Mostly this activity is monitored in the field. However, also look for videos and web posts to identify if this activity is beginning in the wilderness you manage.

Communication: kiosks, websites, and brochures.

Forest Service/Tread Lightly

Related uses: Drone technology is expected to continue to advance and with advancement could bring the ability to carry payloads for delivery into remote Wilderness locals. Though it would be illegal, prohibiting payload delivery could be difficult to enforce. In addition, drone technology is expected to make its way into human transport as well. See the section on helicopters.

 Resources

• Wilderness Stewardship: No Drones in Wilderness
• Information on the FAA’s B4UFLY service.

General: Helicopter landings may be uncommon. Still, documented illegal helicopter landings occur every year in the NWPS. Helicopter landing is more likely to occur in wilderness than fixed wing aircraft due to the space required.

The 4(d) provision allowing the established use of aircraft to continue is important to consider here. Helicopters undoubtedly landed in numerous places prior to wilderness designation. The mere landing of helicopters, however, does not establish it as an allowable use under the special provision. Landing must be public use associated with an identified facility.

Drone technology is expected to make its way into human transport as well. Drones operate on a rotary wing principle. Should the technology develop so that it is safe and inexpensive, wilderness managers can expect to see overflight issues as well as illegal landings. Both occurrences would cause significant impacts to wilderness character and would be difficult to control.

Definitions: any rotary wing aircraft.

Monitoring: Occurrences may be observed by field staff but most likely will be observed by the public and then reported. Providing information on kiosks so that the public knows how to report observed landings, such as where, what, when, and identification numbers, while cautioning the public to not make contact with those involved, is an important way to monitor.

Communication: Assure that wilderness areas are identified on aeronautical charts. Many visitors are not informed about legal aircraft use in wilderness. Complaints about overflights (military, commercial, and general aviation) may occur even though they are legal. Consider providing kiosk information on what visitors should expect where overflights are more common. If there is a potential for illegal aircraft landings, provide information on kiosks for visitors to report (where, what, when, and identification numbers) observed landings.

Related uses: The most common occurrence of helicopter incursions is related to hunting and fishing.

Resources: Hunting rules and regulations of state agencies generally prohibit hunting from aircraft or the harassment of wildlife by aircraft.

General: The Wilderness Act contains a special provision in Section 4(d)(1) which states “the use of aircraft …where these uses have already become established, may be permitted to continue subject to such restrictions as the Secretary deems desirable.” This provides an exception to the blanket prohibition to the landing of aircraft, if a planning decision has been made at places where the use of aircraft was established before the designation of wilderness. Public landing of aircraft in other locations is prohibited, unless a right-of-way for landing exists. The landing of aircraft on a non-federal inholding in wilderness is not prohibited under Section 4(c). The only established aircraft use in wilderness under the 4(d)(1) provision is associated with pre-existing landing strips or helipads.

There may also be provisions for aircraft landing in enabling legislation. For example, ANILCA allows for the landing of float planes in Alaska (The ANILCA provision does not apply to any wilderness outside Alaska).

Facilities associated with allowable aircraft landing may be maintained. Standard maintenance may include: clearing (e.g. trees or brush); mowing; periodic grading; and, keeping wind socks operational. Maintenance activities are determined through a Minimum Requirements Analysis, and typically work is carried out without motorized equipment, despite the maintenance being done to support motorized transportation. For example, grading an airstrip would usually occur using horse-drawn implements. For more information on managing aircraft use allowed under a special provision, take the online course, Managing Special Provisions: Aircraft and Motorboats.

Aircraft sometimes crash in wilderness and must be removed. Sometimes there is an urgent immediate need for rehabilitation such as the recovery of unexploded munitions from a military aircraft crash. Though not an immediate urgent need, aircraft crashes also require accident investigations in a timely manner to assure the cause of the crash is not a threat to other aircraft of the same type. These instances may necessitate the landing of aircraft to investigate the scene and to remove aircraft pieces so that they can be more carefully examined in a controlled site.

After a crash, the National Transportation Safety Board and/or the FAA will investigate, before the wreckage can be removed. After the investigation, it is the responsibility of the owner (normally through the assistance of the insurance company) to remove the wreckage. The agency will identify removal methods through a MRA to accomplish the task with the least impact to wilderness character.

Aircraft crashes, especially military aircraft, may create hazards such as soil contamination and exposure to debris that may contain hazardous materials. Aircraft, especially military aircraft, are increasingly made of numerous composites that may pose a hazardous material concern. In addition, there may be fuel, oils, and live munitions on the aircraft. Some of these materials need to be rendered safe on-site before they are removed. Finally, there may be scars on the land from the impact that need to be rehabilitated. Crashes can be an attractive nuisance leading to impacts from visitors wanting to explore the site. If it is a military crash, there may be classified information involved, which will require guarding the site. Crashes involving these factors will demand specialized clean-up measures which may include temporary helicopter landing areas, use of motorized equipment on site, staging sites, accommodations for guards, and other measures otherwise prohibited in Section 4(c) of the Wilderness Act. Wilderness managers may have little jurisdictional authority immediately after such an event (especially when classified military information is involved). Wilderness management agencies should immediately initiate agreements with the responsible agency/entity so as to provide means by which to participate with crash response officials and integrate wilderness information into the crash response.

Definitions: An aircraft with wings that remain stationary while generating the aircraft’s lift.

Monitoring: It is unlikely that fixed wing aircraft will land in most wilderness areas simply due to the large amount of flat land surface required. Where such areas exist, emphasize monitoring to detect aircraft landing.

Communication: Assure that wilderness areas are identified on aeronautical charts. Many visitors are not informed about legal aircraft use in wilderness. Complaints about overflights (military, commercial, and general aviation) may occur even though they are legal. Consider providing kiosk information on what visitors should expect where overflights are more common. If there is a potential for illegal fixed wing aircraft landing, provide information on kiosks for visitors to report (where, what, when, and identification numbers) observed landings.

Resources:

• Wilderness Connect Special Provisions toolbox
• Schafer Meadows Airstrip Project: 2020
• Schafer Meadows Airstrip Project: 2021 Update

Case Study: Death Valley Wilderness presentation on two military aircraft crashes.

Legal decisions: U.S. v. Gregg, 290 F.Supp. 706 (W.D. Wash. 1968) Page 114

General: Ultralight aircraft tend to be personal aircraft which combine elements of two of the categories above; for example, motorized paragliders. They fly low and slow. These aircraft can be highly disruptive to wilderness settings. Though often a specialty type of aircraft not widely encountered, they may have very dedicated individuals or clubs engaged in the activity, which may be a localized phenomena. They can be landed and taken off from very small openings. Often times they don’t land, but instead fly mere feet above the ground. Videos sometimes show pilots dragging their feet on the ground. Landing is a violation of the Wilderness Act, but flying at low elevations is not. Consequently, the public and agency staff can be very frustrated with the impact ultralight aircraft can have on wilderness character, but may lack the authority or means to address the activity.

Definitions: An ultralight has only one seat, weighs less than 254 pounds, has a maximum fuel capacity of 5 gallons, does not exceed 63 mph, has a power-off stall speed less than 28 mph, can only be flown between sunrise and sunset, does not need to be marked or registered with the FAA, does not require a pilot’s license, and the pilot does not need to possess aeronautical knowledge or experience, or be of a certain age.

Monitoring: Mostly this activity is monitored in the field. However, also look for videos and web posts to identify if this activity is beginning in the wilderness you manage.

Example: King Range Wilderness: Powered Paragliding Video

Communication: Provide information on kiosks for visitors to report (where, what, when, and identification numbers) of observed landings (including any contact with the ground).