Trail Design for Small Properties

Trail Design for Small Properties provides simple, inexpensive solutions for designing, building, and maintaining sustainable trials—trails for hiking, horseback riding, bicycling, cross-country skiing, snowmobiling, off-highway motorcycles (OHMs), and all-terrain vehicles (ATVs).

If designed with sustainability in mind, a recreational trail can provide years of enjoyment. Sustainable trails require minimal maintenance because their design and materials hold up to intensive recreational use and severe weather conditions.

What kind of tread material is best for your trail? Do you need a bridge to cross open water or will stepping stones do? What tools do you need? We answer these questions and more, providing the information you need to make the right choices for your trail.

Determine Trail Uses

The first step in trail design is to determine how the trail will be used, how much it will be used, and what quality of user experience you want to offer.

Multi-use or single-use?

Multi-use trails work if:

• There are many primary users but only a few secondary users.
• The trail is used in different seasons by different users.
• The trail is designed and maintained to accommodate all users, or the trail is divided into parallel treads.
• Clear rules are posted about how to behave (pass, regulate speed, etc.) when encountering other types of trail users.

Consider a single-use trail if:

• Different types of users have different levels of tolerance for noise, effort in using the trail, speed of travel, or influence on the tread.
• You want to offer a high quality trail experience for one type of user.

How much use?

How much will the trail be used at any one time, day, season or year? As trail use increases:

• Increase tread and clearing width.
• Create a more durable tread.

What quality of experience?

Design your trail to fit the user experience that you want to offer. Consider:

• Physical ability of trail users. For example, reduce trail grade if you want to accommodate people with a range of physical abilities.
• Exposure to personal risk (e.g., injury, getting lost) the trail offers.
• Duration of the experience. Is it 30 minutes or 3 hours?
• Purpose for the trail. If the trail simply leads to a destination, choose the shortest and easiest route. If the trail itself is the destination, choose the most interesting route.

Select the Corridor

Perhaps the most enjoyable step in trail design is exploring the corridor to determine where to place the trail. A trail corridor is a wide swath through the landscape that encompasses the trail. Analyze the entire area, refining the trail location as you gather more information.

Use Photos and Maps

Aerial photographs help you identify land uses on your property and neighboring properties (e.g., cropland, pasture, forest, river, lake), roads, trails, buildings, and utility rightsof- way (fig. 1). Look for photos in a scale of at least 4" to 1 mile, but preferably 8" to 1 mile. Photos are often available from the state department of natural resources, especially the state forestry agency; U.S. Department of Agriculture, Farm Service Agency; U.S. Geological Survey; and Web sites.

Topographic maps (1:24,000 scale) are helpful in hilly and mountainous terrain, especially if your trail covers a large geographic area (fig. 2). They show elevation changes, forest and open areas, rivers, lakes, wetlands, buildings, roads, trails, cemeteries, and other features. Topographic maps may be available from the U.S. Geological Survey, commercial CDs and DVDs, map dealers, and recreational outfitters.

Soil maps and accompanying data tables describe the suitability of soil types for roads, structures, farming, forestry, etc. (fig. 3). Soil maps may be available from your local soil and water conservation district, USDA Natural Resources Conservation Service, county Extension office, or Web sites.

When evaluating large sites, other maps or geographic information systems may provide information on water resources, rights-of-way, utilities, land uses, roads, land ownership, vegetation cover types, wildlife habitat, flood zones, etc. Possible sources include state or national natural resources agencies, local planning and zoning authority, and universities.

Scout the Trail Corridor

Scout the corridor in the trail’s primary season of use. To clearly see landscape details, scout when deciduous trees have lost their leaves. If possible, scout in all seasons to reveal attractive features and hazards that may affect location, construction, or maintenance. Look for:

• Spring: high water, ephemeral ponds, flowers
• Summer: dense foliage, normal water level
• Fall: foliage color
• Winter: icicles, snow scenes, frozen water

Note existing trails and roads, control points, obstacles, points of interest, and anchor points (fig. 4). Take notes and mark locations on a map or record GIS coordinates.

• Existing trails and pathways. Existing trails and roads may be good links to new trails. Also look for natural pathways that require little clearing or construction (e.g., a ridge top, hillside bench, or river bank terrace).
• Control points. Control points are physical or legal constraints on a trail’s location. Ownership or management unit boundaries, a steep slope forcing a trail through a narrow section of hillside, a cliff that forces a trail around one end, a wetland forcing the trail along a narrow upland ridge, or a stream that can be crossed easily in only a few places are examples of control points.
• Obstacles. Obstacles can include a steep slope, rocky soil, boulder field, rock slide, sand dune, cliff, rock ledge, eroding bank, steep-sided gully, gorge subject to flash floods, water body, wetland, habitat for rare species, historic and cultural sites, fence, highway, sources of objectionable sound, and objectionable views. Obstacles may require expensive crossing structures.
• Points of interest. Run your trail past significant points of interest, e.g., unusual landforms (sink hole, esker, sand dune, hill, valley, gorge); different forest types or ages; forest opening; grassland; farm land, especially if it attracts feeding wildlife; scenic vista; boulders; rock outcrop; wetland; ephemeral pond; lake; river; creek; waterfall; historic site (may also be an obstacle); archeological site (may also be an obstacle); and wildlife habitats (den trees, rock piles, dense thickets, layers of forest vegetation, water sources, sand banks, cliffs, caves, crevices). Attract wildlife to the trail corridor with nesting boxes, breeding sites, food plots, feeding stations, roost poles, watering devices, and other constructed habitats.
• Anchor points. At frequent intervals, take the trail past subtle anchor points (e.g., large or unusual tree, rock, patch of shrubs) that add interest and draw attention to landscape features.

Additional Points to Consider

• Avoid placing your trail in areas with threatened or endangered flora, fauna, geology, and natural plant communities. Ask your state’s department of natural resources whether these resources exist or are likely to be found on or near the trail location.
• Protect cultural resources such as historic structures (buildings, dams, bridges, fire towers, etc.), archaeological sites (above and below ground), cemeteries (including unplatted historic cemeteries, burial mounds, and other ancient burials), and traditional-use areas where natural resources are gathered for food, medicine, or ceremonial uses. Cultural resources can be damaged by soil disturbance, soil compaction, rutting, change in public access, and change in vegetation and other features. Whenever a government permit, license, or funding is needed for a project, a cultural resources management review may be required. To learn about locations of cultural sites, contact a state archaeologist.
• Discuss your trail project with neighbors to learn about the impact on their properties and potential linkages to other trail systems.
• Consider your budget for land and right-of-way acquisition, construction, and maintenance. This will put a reality check on your design plans.

To Learn More

• Contact your soil and water conservation district to learn about rules affecting trails over streams and wetlands.
• Contact the governing road authority to learn about rules for trails that cross or follow roads.

Establish Design Standards

After exploring the trail corridor, but before flagging the exact trail location, set your design standards. Base the standards on the trail uses; the quality of experience you want to offer, including the level of risk; and your construction resources, including budget and expertise. Use the Recommended Trail Design Standards on pages 6 and 7 as a starting point. Modify them to fit your needs.

Consider these aspects of the trail design: trail configuration, trail length, tread surface, tread width, clearing width, clearing height, grade, turning radius, sight distance, water crossings, and special requirements.

Trail configuration is the overall shape of the trail.

• Linear trails are appropriate for long distance travel (several miles) or where the land ownership (right-of-way) is too narrow to permit development of a loop trail.
• Spur trails are short linear trails that take users to points of interest or connect different loop trails.
• Loop trails permit the user to begin and end at the same location without repeating any part of the trail.
• Stacked loop trails (a series of interconnected loops) permit users options for different distances, routes, or destinations.

Trail length is the distance that users could travel in one day.

Tread surface refers to the type of surface material (e.g., soil, gravel, rock) and its condition (e.g., smooth, rolling, rough). High-use trails require more durable materials and smoother surfaces than light-use trails.

Tread width is the width of the useable trail surface. In general, the tread width that is suitable for light-use or one-way travel should be doubled for heavy-use or two-way travel.

Clearing width is the total width to which rocks, trees, tree limbs, and other obstacles should be removed. As a general rule, clear at least 2' on each side of the tread. Where a trail passes through dense vegetation, vary the clearing width to avoid an unnatural tunnel effect. In general maintain clearing width from the ground up to the clearing height, except you may leave vegetation, rocks, and other objects less than 2´ tall near the tread edge. Center the tread within the clearing width, except on hillside trails where clearance may be less on the downhill side.

Clearing height is the height above the tread surface to which overhanging rocks, tree limbs, and other obstructions must be removed. As a general rule, clear 2´ above the user’s head. Keep in mind that leaves will bend deciduous tree branches 1–2' lower in summer than in winter and snow will bend evergreen tree branches and raise the tread surface.

Grade is the slope angle (expressed in degrees or percent) along the trail’s centerline.

% grade = (degrees of angle) x (tangent)

It is easy for trail users to travel long distances on low grades. High grades require more work and should extend for shorter distances. Measure grade with a commercial or homemade clinometer (fig. 7).

Turning radius is the radius of an arc drawn through the centerline of the tread where the trail curves. As travel speed increases, lengthen the turning radius, bank the trail higher on the outside edge, widen the trail, or clear a runout zone (fig. 8).

Sight distance is the distance that a user can see down the trail from any point on the trail. Adhere to the recommended minimum sight distance, but vary sight distances to add interest. Lengthen sight distance to allow faster travel and reduce sight distance to slow travel.

Water crossings refer to the type of structures recommended for crossing bodies of water. A ford, stepping stones, culvert, boardwalk, or bridge may be appropriate. Your choices will be affected by the type of user, type of experience you want to offer, type of water body, length of crossing, legal status of the water body, your ingenuity, and your budget.

Acknowledgments

Authors:
Mel Baughman is Associate Dean and Extension Forester in the College of Food, Agricultural and Natural Resource Sciences at the University of Minnesota.

Terry Serres is a graduate student in Natural Resources Science and Management at the University of Minnesota.

Editor/Design: Julie Roles
Illustration: John Molstad