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A Total Forest Management Plan and Wildland Management Decision Support System
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The Access and Delivery System: Road Location and Management

Impervious Surfaces of the coterminous USA from http://dmsp.ngdc.noaa.gov

The continental US has 6.3 million kilometers of public roads, about 1/4th classified as non-local roads in rural areas. Constructing and maintaining such impervious surfaces as buildings, roads, turnouts, and parking lots constitute a major human alteration of the Earth's land surface - changing local hydrology, climate, and carbon cycling. Satellite studies show in the US that there are 112,610 square kilometers of impervious surfaces, an area nearly the size of Ohio. For comparison, there are 5.3 million kilometers of streams and rivers. More than comparison, the lengths and their zones of influence suggest potential road impacts on forests and streams.

Access to areas for getting to their resources are important, but there can be differences in going to and leaving an area. Often removing resources like logs can require different structures and conditions than those of simple entrance or gaining access. In some areas people can be delivered to a site and they can walk in or bike out. In some areas, "things" do not have to be delivered, only information (such as medical advice which can be done by wireless devices or telephone). In this section of The Trevey we recommend keeping a broad view, emphasizing the objectives of moving ideas and things, and not just thinking about roads or trails. Within the access system we include hiking, jogging, horse, and biking trails; roadways (used for wagon rides); snowmobile zones; boating and fishing reaches of lakes and rivers; bridges (there are 11,000 bridges on National Forests); tramways and ski-lifts; and easements from neighbors to gain or maintain access to the edges of the property.

Roads

Rain Impact and Runoff Velocity

Owners need to keep in mind that

• concentrated flows,
• reduced infiltration,
• increased slopes,
• removal of surface cover,
• and interception of subsurface flow (springs and seeps),

To utilize the resources of the property a road system must be developed. It is cost effective, even in inflationary times, to invest in a high-quality, well-designed, well-engineered and protected road system. Such roads provide access, allow resources to be removed, allow potential resources to be used, allow management and improvements, and allow monitoring and inspection of managerial actions and their consequences. They are essential for protecting areas from wildfires and insect attacks. They reduce hauling costs, prolong equipment life, and reduce equipment down-time. Because roads are the major contributor to siltation and watershed problems, road design is needed to minimize these influences. Roads provide secondary advantages to wildlife, both plants and animals.

A good way to get up the hill... but that will not last long. Every bulldozer operator cannot build an excellent road. Grade, slope steepness, culverts, surfacing, culvert use and placement and protection from the outflow, waterbars, and re-vegetation are important tactics that need to be joined.

While road costs are high and road maintenance costs will persist, actual timber movement costs are reduced, distance for distance, along roads than across country (Rowan 1976:1). Inventory and management costs are substantially reduced by roads. Because wood haulage has the most stringent requirements for road layout and design, roads are to be built for this purpose. Other needs will be met by such roads.

The criteria for roads are:

1. Producing minimum intrusion of wild or natural-preserve areas
2. Reaching the maximum investment limit
3. Incurring minimum actual construction costs
4. Meeting standards and guidelines
5. Being appropriately designed for the volume of wood accessed
6. Having minimum likely maintenance costs
7. Providing maximum taxation advantages
8. Providing maximum gating opportunities for road protection
9. Having maximum esthetic protection and enhancement
10. Having minimum runoff velocity into adjacent forests
11. Delivering minimum sediment off-site
12. Having minimum fossil-energy consumption costs for vehicle operation
13. Having maximum benefits to highly valued wildlife
14. Having minimum disturbance to wildlife behavior (e.g., migration)
15. Having maximum positive net influence on the local fishery
16. Having maximum safety provisions
17. Providing maximum fire protection
18. Causing minimum wind damage or negative influences, blowdowns, or reduction in adjacent site quality.

Typically we recommend that in the first 2 years, harvesting be done by cable from the road edges. Subsequently a computer system will be developed for optimizing spacing and road developments based on prior work of Gardner, Elsner, and others.

High-quality roads are a part of high quality land management. Trees are conspicuous; roads are essential and very important to long-term land productivity. Rural System staff can plan, construct, re-construct and manage your roads. In the region, complexity of ownership, age of existing roads, and costs of road construction make improving any road a set of complex and difficult decisions. The 3-R's usually apply:

• Re-design,
• reconstruct, and
• restore.

Inside ditch will cause much erosion. Outsloping road would have been better. Upper culvert too high and not slanted; erosion will follow. Culvert at bottom functionless. No waterbars.

We integrate a large set of what are called "Best Management Practices" (BMPs) onto your land to fit the site-specific conditions. Literally massive differences can be made in net land productivity and cost reduction by proper location and design of roads. We assure a safe layout, proper slope, good drainage and sunlight, superior supervised construction, minimum cost, turnouts with minimum road with and impact, then ease of maintenance. Few people realize that short, steep roads designed to reduce construction costs increase operation and maintenance costs over many years. The net result: it doesn't make sense to build poor roads. Such roads tear up equipment, cause down-time, cause accidents, cause erosion, reduce recreation potentials, destroy stream and fishery benefits, and open the owners to legal action by downstream land/water owners.

Roads are essential for many uses such as cost-effective inventory, recreation, fire control, rescue, studies, firewood gathering, and logging. These roads are avenues of public exposure to hikers, skiers, motorists, and to the owners themselves.







There may be negative

Outflow of culvert not protected (there will be a hole below the pipe soon; steep outer bank; little revegetation, sharp inner ditching; long "runs" of runoff.

effects of roads on forest values like esthetics and recreation and thus controversies arise...and thus there is need for management of the potentials for controversy and the controversy itself. Controversy ranges among recreationists, for example, as a means of access, a need to get far away from them, and some who prefer to spend all of their time driving on them. There are 300,000 miles of roads in the National Forests, half passable with high-clearance vehicles.

In nine central Appalachian areas logged with wheeled skidders, there was 1 mile of road for every 19.8 acres; roads and landings occupied 10.3 percent of the area. In two areas logged with jammers, there was 1 mile of road for every 31.1 acres; roads and landings occupied 7.8 percent of the area.(Kochenderfer, J. N.1977).

While there are real concerns about clearcutting and its effects, few people realize that if the alternatives for tree harvests are to be practiced, then there must be a tight network of logging roads for log removals. Group selection, as single-tree selection, can only be practiced cost-effectively and with minimum impacts on soil, understory vegetation, and on residual crop trees if there are short skidding distances (from stump to road or log deck).

Timber harvest effects cannot be separated from road effects. It is useless, even silly, to claim that harvests have little effect on soil erosion when it is well known that roads can be a major erosion source )typically called "non-point source pollution." A source for information on water quality and best management practices in logging is now available.This simply means that they must be well located, well designed, well constructed, and then well managed, and in some cases "retired". The energy costs, financial investment, and tree-growth potential foregone when a road is built is so high that within The Trevey, we rarely recommend retiring roads but of course maintaining them for, by design, they can be easily maintained (or else they are rarely built). Like planting a forest, building a road is not a one-time act. It is an act that may last for centuries and affect people (and their resource use,benefits, and costs) for at least that many years. Typically, 1 mile of forest road about 8 feet wide takes out of tree production about 1 acre. It also increases runoff. One mile of road hit with a half-inch rain will deliver 13,500 gallons water of to the edges and streams. EPA has an important publication.

A key to superior road work is to imagine a flow of water about 6 inches deep coming down across the land surface and then to imagine trying to block that! When a road is cut into a hill side, all of the water flowing across the surface must run over the road ...or down it. The job in road design and maintenance is to prevent it being blocked, pooling up, gaining momentum, or carrying "scouring powder." A flow of 6 inches may seem extreme, but the road design must be for the high-intensity rain. Even small rains produce surface flows at road-side bank cuts. Not to prepare for peak flows is to gamble and to assure road problems for someone else within a few years. A sustained road system for sustained flow of products and services for profits is the objective. A smooth, efficient road system is needed so that there will be minimum machine breakdowns, minimum energy costs, and maximum equipment life.

Proper Placement of Waterbars in Roads
Road Grade		Distance Between Waterbars
Percent	Degrees	Feet	Meters
2	0.9	240	72
5	2.25	120	36
10	4.5	60	18
15	6.75	40	12

It is well recognized that water needs to be moved off roads and that erosion from the surface or edges of roads needs to be controlled. Many devices exist for doing so and these are documented in many descriptions of Best Management Practices (BMPs). These include filter areas, rapid revegetation, soil erosion devises and substances on roadside cut areas, waterbars and broad drainage dips. "Nailing down" the land is a key strategy with in The Trevey but the primary work is in locating the network of roads for an area. The concept is to mark areas where roads should not be placed, then those areas where they may not be placed (e.g., preserved areas); then to cover the ownership with roads (and their zones of influence) of minimum length, minimum grade (and always less than 15% slope), on compatible soils; and where vistas may be provided or enhanced. Meeting all of these needs is best done by computer and the GIS.

Reducing the area under road surfaces (where trees do not grow) is one objective for the tree grower, but the total resource production system over the 150 year planning period is the topic. Reducing costs of road (all aspects) is another objective. Except for wilderness-like conditions (typical on public lands), the potentials for diverse resource gains and protection (e.g., fire) are best achieved by an extensive, well-designed and managed road network. Roads are not intrinsically bad and seemingly must be viewed as impacts. Well designed roads and trails can be beautiful and also the means to reduce the risks from investment in and to derive benefits and profits from the forest.

Make the roads as narrow as possible (especially in high erosion areas) and as far from streams as possible.

Slope the road surface 3% to allow water to run off.

Use broad based road dips instead of culverts and space then

Spacing = (44 + slope percent) (Kochenderfer 1970)

The zone of influence is the road and typically on each side a zone may be drawn at a set distance. For example, from limited studies it is known that few hunters move more than 0.6 mile from roads. That number can be used as the width of the zone and a map made to show the potential hunted zone (and within many areas, the "non-hunted" residual area. Similar zones can be created for economic log skidding distance, poaching, use by hikers, noise attenuation, heavy metal pollution (vehicle tires and gasoline), and other factors.

Viewscapes can be created from set points along roads (using GPS) or arbitrary viewing sites established (e.g., every 1000 feet along a road). Each viewing site is selected and the computer "looks off" in all directions and maps the are which can be seen. The same area can be seem from many such site. The more visible, the lower will be the rank of such areas for harvest (because of disturbance to the many likely users of the area's roads).

Most damage occurs within the first 2 years following construction. Solutions:

• plan the road layout well
• lay out roads with a maximum slope of 15%. Where access is impossible with such a slope, use switchbacks (also with gentle outslopes of 2-3%)
• remove the berm (caused by grading ) at road edge to allow the outslope to work
• on existing roads that are badly rutted, smooth them, outslope them at a gentle angle (2-3%), and install waterbars. In most cases, relocate them to avoid moisture problems. Seed and fertilize the smoothed former roadbed.
• have construction supervised
• include BMPs and related provisions (including this document) within logging contracts
• avoid over-winter construction
• plan completion of construction to coincide with best seeding periods
• mulch, lime and fertilize after seeding
• create logging slash barriers
• on steep areas, fasten down mulch with netting, liquid asphalt, or various polymers (e.g., petroset)
• make cut and fill slopes as short as possible and with the least slope possible
• build terraces on cut slopes as necessary to manage the water there
• compact the fill slopes as they are constructed
• use leaf blower to blow native seeds and duff from the forest edge onto cut/fill banks
• seed fill areas
• frequently create broad-based drainage dips within roads(see the table)
• build waterbars as follows (see sketch). Build after the road bed is in place.Level the road and cut a waterbar into the bed. Cut a notch at a 30-degree angle to a line perpendicular to the road. At the outer edge, the notch should be a 4 to 6 foot wide and 6-8 inches deep.
• use reverse grade in small sections of the road ( a hump) to intercept water and sediment and force it off the outside edge of the road
• make multiple exit points for water
• prevent water collection points
• protect channels at drainage structures by placing rock or masonry headwalls.
• prevent opportunities for buildup in water momentum (buildup is a function of increasing slope and length of the run (slope x length))
• where the road bed stays moist, the surrounding trees should be cut and the road daylighted to encourage evaporation. Use grasses to vegetate the area.
• put a 3-inch gravel surface on select sections (soil losses are 8 time greater from bare roadbed than from gravel surface)
• surface roads as follows:
  • Light traffic: gravel or dirt
  • Moderate traffic: gravel
  • Heavy traffic: paving
• surface sections on either side of a stream ford to reduce sediment movement directly into the stream
• revegetate immediately after road work; keep erosion control work current with road construction.
• install drainage work from the bottom up (downstrean to the top)
• rarely create a drainage ditch on the inside edge of roads (increases sediment 5 to 7 times)
• outslope roads 2-3 % (in extremely icy conditions and excessively sloped roads when this resulting surface may seem hazardous, road use should be stopped)
• gently outslope switchbacks
• exercise careful design and velocity protection on culverts (which are rarely used)
• stop road use during adverse conditions (e.g., frost heave, excessive moisture). Work only during dry periods to minimize stream disturbance; when wet, use only main access roads
• where dips or culverts collect water, the fill slopes should be protected with downspouts to the bottom of the fill or to emergency dissipators such as rock basins
• for long steep stretches of road where the soils below the road are not vegetated and cannot handle the water, then a culvert should be placed there. The water will be carried in this culvert down the slope to a vegetated area or stream.
• use culverts to move waters from springs and seeps under roads and into channels, settling ponds, or filter beds
• where metal culverts are used to carry water across an insloped road, they should be burried 2-3 feet deep to prevent damage from traffic
• if roads are far from streams, and roads are insloped, little mitigation of erosion effects is needed. If close, then you must line the channel with rock, vegetate well, or build control structures.
• do stream drainage development from downstream, upward and only during dry periods.
• be selective in road maintenance. It can disturb stabilized roads and contribute to soil loss.

As self-evident as some of these above suggestions seem, few loggers or private land owners as late as 1998 did not know of them or did not realize there were laws related to BMPs.

Stream Crossings

Stream crossing are key sources of sediment and erosion problems. They are said to be the most expensive and challenging task in developing forest access systems. water can easily flow down the approach segment of the road into the stream.

In 1999, low-standard roads cost about $8100 per mile.

Costs of using BMPs is about $2.35 per mbf but training of loggers may increase this cost. (Who knows what the cost over 100 to 150 years is of not training them?)

Off road vehicles and their use are discussed elsewhere.

Signs need to be used along with education to dispel misinformation about the costs of roads, their impacts, etc. and to express the benefits (including the ecological benefits, recreation, fire protection, and rescue speed) provided by well designed and managed roads.

Roads, when well designed and well drained, can be used longer than other roads. Roads should be closed or not used when weather is poor and rutting likely.

Road edges, banks, log landings, skid trails and other disturbed areas should be cleaned-up and seeded. While appearance is important, getting a good seed bed and stopping erosion (from a hard rain that can come the day after you have sown seed!) is more important. Appearance will be satisfactory within a year. Of course, oil cans, machinery, etc. need to be cleaned up. The ground does not have to be made into a "yard" for grass. Create ridges on the contour (e.g., with a root rake); pile brush and litter in rows on the contour; build flat ledges; place rocks on the contour. Too much time and money has been spent on "smoothing" areas. We want low contour-level vegetation and earth ridges. In some areas, a bulldozer, while building or grading roads, can create contour-level, stair-step areas. These will soon have a pleasing appearance, once seeded with wild plants, as well as prescribed grasses and shrubs. A "leaf-blower" can be used to move materials from the forest onto road bank cuts with great "natural seeding" success. Specific site-determined seeding recommendations can be produced by computer programs.

We recommend reducing use of roads by logging (etc.) from May 1 to October 1. This reduces disturbances to many game birds with broods and when nesting. Reasonable levels of use by hikers and educated outdoors people will not be disruptive and these are periods when animals are of great interest and appeal.

We recommend using roads only when they are dry. We also recommend slow travel and attention to turn-outs. Loaded vehicles going down hill have the right of way no matter what the distance to a turn-out.

Rarely are there problems with forest roads and wildlife but they may influence migration and behavior. They provide special edges and planting opportunities. Rarely are collisions a problem. They create special law enforcement problems related to their being open or closed. Other notes on roads and wildlife are available.

Crescent: The Watershed Strategy

Much of the above discussion had as its background desirable or improved watershed management and is a reasonable part of the Crescent strategy. In addition to and as part of that strategy, the following road building and assessment guides may be useful:

1. minimize road density
   • your road density is _____miles per acre, or
   • your road density is _____kilometers per hectare
2. locate so each is highly functional, providing access to (1) large areas or (2) specific target sites
3. has no road sections with slopes exceeding 15%
4. has minimum stream crossings
   (your area has _____ crossings.)
5. does not pinch or constrain streams (e.g., with culverts, bridges, walls)
6. has sediment filters
7. has few culverts, but when used, only at key areas
8. develops rolling grades to minimize cuts and fills
9. avoids unstable areas
10. has provisions for closure during adverse weather or soil conditions
11. is located (or re-located) away from streams and riparian areas, is outsloped, and re-vegetated. (If not re-located (from a poor position), maintenance time and costs are increased, surfacing may remain a problem, and closures are increased).

Feedback

Given the difficulties and high costs of roads and access it is essential to develop a functioning feedback system for them. The full design will not be presented here but it needs to include the range of objectives and whether roads are needed to achieve them, costs present-discounted, maintenance costs annualized, use-rates estimated (e.g., by traffic counters or cameras), and at least modest monitoring done of runoff and sediments. Time and energy costs of access within the ownership from a fixed point, (a nearby town, main office, transportation center (rail or air) is needed). Percent of development of the planned system is needed as one type of score. The quality of roads can be judged on 5-10 criteria and that score reported to the officers of the company and to the public. Kilograms of sediment per liter (e.g., 300/liter) at measured distances downstream from crossings should be compared to natural streams and to waters above structures. Generally there is extinction of the silt load far down stream and this needs to be reported. The length of the sediment influence within the stream may be shortened by good works. (Higher streamflow rates will transport greater sediment loads and heavy vehicles will generate more sediment than light vehicles.) Bridges are more expensive than fords or culverts but introduce the least silt of the crossing methods. Use them wherever possible. Culvert installation produces much sediment but they produce less sediment than fords. Rubber mat dam bridges can reduce sediment loads. Effects of sediments on the biological function of the streams that are influenced is a major job and new methods are needed to grasp the mix of forces of silt, soil, vehicles size, numbers crossing, precipitation and season, stream flow rates, natural turbidity, underwater or wetted surface impacts, and changes in abundance and richness of organisms in the stream. We need to formulate a relationship between the benefits of land use and harvests, their direct reasonable costs, and tolerable indirect or secondary resource losses or costs.

Continual work is needed to find cost effective methods for local conditions. In one study (Grace 2002) found native vegetation was as effective as exotic species vegetation and erosion mats in reducing sediment from forest road side slopes. There remains work in finding out how much sediment leaving roads is delivered to streams.

See additional notes, especially on effects of roads on wildlife..

References

Egan, A.F. 1999. Forest roads: where soil and water don't mix. J. Forestry 97 (8):18-21.

Elliot,W.J., D.E. Hall, and S.R. Graves. Predicting sediment from forest roads. 1999. J. Forestry 97(8):23-29.

Elliot, W.J. and L. M. Tysdal. 1999. Understanding and reducing erosion from insloping roads. J. Forestry 97(8): 30-34.

Grace, J.M. 2002. Sediment movement from forest road systems - roads: a major contributor to erosion and stream sedimentation. Amer. Soc. Ag. Engineers 13-14

Kochenderfer, J. N.1977. Area in skidroads, truck roads, and landings in the central Appalachians. J. For. 75: 507-508, illus.

Kochenderfer, J. N.1970. Erosion control on logging roads in the Appalachians. Res. Paper USDA Forest Service, NE Forest Exp Station 28p.Upper Darby PA

Morris, J. 1995. Earth roads. Avebury, Old Post Road, Brookfield, VT 05036-9704 USA, 242p.

Taylor, S.E., R.B. Rummer, K H. Yoo, R.A. Welch, and J. D, Thompson. 1999:What we know and don't know about water quality at stream crossings. J. Forestry 97(8):12-17.

Swift, L.W. Jr. 1984. Gravel and grass surfacing reduces soil loss from mountain roads. For. Sci. 30(3): 657-670

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Last revision Sept 24, 2004.