Appendix Appendix F 

Appendix F 

Best Management Practices 

and 

Road Standards for Proper Drainage 

Introduction Introduction 

The following Best Management Practices, considered to be the most applicable to the planning area, were 

derived from a number of sources including: BLM OR/WA Manuals and Handbooks, Oregon Forest Practice 

Rules (Oregon Department of Forestry, 1980), Moll (1999), the US Forest Service San Dimas Technology Center, 

and internal RMP scoping comments. scoping comments. 

Road Construction and Maintenance Guidelines Road Construction and Maintenance Guidelines 

For additional, more detailed specifications concerning all aspects of road design, construction and maintenance 

refer to BLM Manuals 9113 - Roads, and 5420 - Preparation For Sale (Timber). refer to BLM Manuals 9113 - Roads, and 5420 - Preparation For Sale (Timber). 

New BLM system road construction would focus on redesigning existing road systems for beĴer access 

efficiency, recreation use, reduction in conflicts with adjacent landowners, and resource protection. Road system 

management would include maintaining existing roads, seasonal closures, permanent closures and rehabilitation 

of roads. Existing system roads would be maintained for proper water drainage and long-term service. ater drainage and long-term service. 

Any new roads would be designed to minimum standards consistent with the proposed use and traffic safety 

(see Table F-1). An in-depth field review for each feasible location should be performed prior to construction. For 

each feasible location, consider environmental impacts and resource value impacts, including suitability of soil 

and geology, potential for road surface erosion, and impacts due to extension of the drainage network on water 

quality and quantity. Consult hydrologists and fisheries biologists for stream crossings. Surfaced roads would 

include some county roads, roads receiving heavy use by the public, and some approved road rights-of-way. 

When designing long-term road networks, existing roads would be incorporated to the maximum extent possible 

unless new roads offer beĴer long term conditions for resource conservation, visual resources, recreation or 

reductions in conflicts with adjacent landowners. icts with adjacent landowners. 

Geometric Standards-Design speeds, travelway widths, and maximum grades for various combinations of 

estimated average daily traffic (ADT), functional classification, and terrain types are shown in Table F-1 below: able F-1 below: 

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Functional 

Classification 

Estimated 

20 yr. ADT Terrain Design Speed 

Travelway 

Width Maximum Grade 

Resource 

Less than 20 Level & Rolling Preferred Minimum Preferred Minimum Preferred Minimum 

30 * 14 * 8 10 

Mountainous 15 * 14 * 8 16 

Local 

Less than 100 Level & Rolling 40 30 20 20 6 10 

Mountainous 20 15 14 12 8 15 

More than 75 Level & Rolling 50 40 24 20 6 10 

Mountainous 30 15 24 20 8 14 

Collector 

50-150 Level & Rolling 50 30 24 20 6 8 

Mountainous 30 20 24 20 8 12 

More than 

100 

Level & Rolling 50 40 24 20 6 8 

Mountainous Mountainous 30 20 24 20 8 12 

Upper Deschutes Record of Decision and Resource Management Plan ce Management Plan 

Table F-1 Road Standards able F-1 Road Standards 

*If preferred design speed and travelway width are not feasible for specific resource roads, alternate values are determined by District 

Resource Specialists. Resource Specialists. 

Road location would be designed to follow the terrain to minimize excavation to the essential amount needed 

to meet necessary road standards. Whenever possible, roads would be located away from streams, meadows, 

and riparian areas. Appropriate drainage structures would be incorporated into construction or reconstruction 

design. design. 

Cut and fill slopes would be revegetated, preferably with native vegetation, to stabilize the slopes and reduce 

erosion. erosion.erosion. Seeding or planting would be done the first fall season following construction of long-term roads. rst fall season following construction of long-term roads. 

A local road with a design speed of 20 mph or less should be outsloped for sections where the grade does not 

exceed 6%. Outsloping roads is not recommended unless the subgrade materials are resistant to erosion and 

traffic volume is extremely low. All other roads should be crowned to ensure proper drainage. All other roads should be crowned to ensure proper drainage. 

Side ditches should be constructed adjacent to, and parallel with, the roadway shoulder. The ditch collects runoff 

from the roadway and from adjacent upslope areas. The shape and dimensions of the ditch are selected to carry 

adequately the anticipated runoff from a major storm without saturation of subgrade or surfacing material. from a major storm without saturation of subgrade or surfacing material. from a major storm without saturation of subgrade or surfacing material. 

Where overtopping of the road could occur, a dip or grade roll should be designed to ensure that the overtopping 

flow crosses the road at a point that minimizes erosion (erodible-resistant surfacing is oĞen added), and so that 

flow is not diverted along the road or away from its natural flow path. ow path.ow path. 

For low-volume roads, surface cross drains provide an economical alternative to using ditches and culverts. 

Surface cross drains can be designed into any shape road surface template to divert water collecting on and 

running down the traveled surface. Surface dips are not recommended for grades over ten percent because of 

the steepness of the dip approach grade that would be required. Cross drains may also be used to relieve ditches 

and the inside edge of insloped roadways without ditches. Ditch dams are used to direct ditch water into the 

cross drain. Surface cross drains should be located at intervals close enough to prevent volume concentration 

that causes surface erosion or unstable slopes. Cross drains should be constructed with an outslope grade of 3 to 

5 percent or equal to the existing out-slope grade. In colder climates where snow and ice create driving hazards, 

the outslope grade should be reduced. For drivable dips, the minimum freeboard should be 150 millimeters 

with a roll-out length of at least 6 meters. If the dip is unarmored, freeboard should be increased to allow for 

the tendency of the dip to lose its shape due to traffic. Drain dips and drivable water bars negotiable by highclearance v clearance vclearance vehicles hav ehicles havehicles have steeper rollout grades. e steeper rollout grades. The abov The abovThe above values should be adjusted according to local climate. alues should be adjusted according to local climate. 

Locate cross drains far enough above stream crossings to avoid releasing drainage water directly into stream 

channels. Whenever possible cross drains should be located to release water on convex slopes or other stable areas 

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Appendix Appendix F 

that will disperse water rather than channeling it. Surface and ditch water should be diverted and dispersed 

before it enters streams using lead-out ditches, seĴlement ponds, ditch dams, surface shaping, or other measures. 

Cross drains and outlets should be armored where soils are highly erodible or provide poor traffic support during 

wet weather use. eather use. 

Dip orientation (skewed or perpendicular to the road centerline) depends on the type of traffic expected, length of 

the dip, and road grade. If dips are shorter and the traffic will include larger trucks with longer frames, then the 

dips should be oriented perpendicular to the direction of traffic. Dips skewed from perpendicular to centerline 

more effectively drain steep road grades, are more comfortable for vehicle occupants, and, if long enough, will 

not cause severe twisting of truck frames. ere twisting of truck frames. 

Culverts would be designed for all streams to pass a 100-year flood. Culverts would be designed for minimum 

impact on aquatic life. Open boĴom shapes should be used if it is necessary to maintain the character of the 

streambed and would be the preferred option for fish-bearing streams. If a closed boĴom shape is used in a fishbearing stream, the type, size and gradient of the culvert should be assessed using the most current method of 

design for fish passage (for example, a soĞware application for Windows called “FishXing, “developed by the Six 

Rivers National Forest Watershed Interactions Team available from the Stream Systems Technology Center (www. 

stream.fs.fed.us/fishxing) or from the USDA-Forest Service San Dimas Technology and Development Center). 

Rock or other appropriate lining would be provided for culvert outlet basins. ert outlet basins. 

Waterbars would be installed on skid trails and temporary roads where there is potential for erosion due to soil 

type, terrain features, or future human uses. Waterbars are typically used in closed-off areas with liĴle traffic, and 

should be oriented to lead the flow from the surface. One rule of thumb is to add five to the percent road grade 

and orient the waterbar at that many degrees off perpendicular perpendicular. 

All roads would be maintained during logging, mining, or other activities involving heavy vehicles or multiple 

trips. Roads would be maintained during and immediately aĞer use periods as needed to control erosion and 

road degradation. Maintenance activities could include reconstruction, snow plowing, grading, cleaning ditches 

and culverts, installing new drainage structures, and replacing surfacing. Maintenance frequency would depend 

on traffic, weather, road condition, and soil type. During heavy industrial use, roads would be monitored during 

wet conditions and temporarily closed, if necessary, to prevent excessive damage. e damage. 

All necessary road permits and road use agreements would be obtained before beginning industrial operations. 

Individual road use permits, agreements, contracts, and right-of-way grants would provide detailed stipulations 

for road use and maintenance for specific roads. c roads. 

Temporary access roads would be closed and stabilized by a combination of the following methods: signing, 

blocking, disguising, scarifying, waterbarring, seeding, and mulching. aterbarring, seeding, and mulching. 

Design drainage ditches, waterbars, drain dips, culvert placement, etc. in a manner that will disperse run-off 

and minimize cut and fill erosion. Design of drainage ditches, waterbars, etc. will be done in a manner to ensure 

safety for road users. safety for road users. 

Blocking and disguising would utilize large logs, branches, stumps, and/or boulders found in the local vicinity. 

Tees cut from adjacent areas may also be imported to facilitate road closures and rehabilitation. ees cut from adjacent areas may also be imported to facilitate road closures and rehabilitation. 

Closed and obliterated road beds would be recontoured to match the adjacent natural slope and would be seeded 

with native seed. e seed. 

Background of Road Influences on Hydrology uences on Hydrology 

Proper drainage, from a watershed standpoint, is minimizing the cumulative volume-distance quantity 

of displacement by appropriate road and drainage feature location and design, coupled with appropriate 

routine maintenance. Three main components of proper drainage provision are: road location and design; 

drainage feature type, location, and design; and appropriate routine maintenance. Proper drainage provision is 

accomplished on each unique road segment by ensuring location and design of road alignments and drainage 

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Upper Deschutes Record of Decision and Resource Management Plan ce Management Plan 

features minimize changes to natural disposition of precipitation and groundwater. Road location must 

consider alignments, template geometry, aspect, location on hillside, geology, climate, vegetation, operational 

requirements, season of use, and management activities on surrounding terrain. Drainage feature considerations 

include type, spacing and shaping, applicability of drainage schemes to site conditions, including investigation of 

opportunities on the ground for minimizing water concentrations and their effects on areas adjacent to the road 

segment. segment. 

Appropriate routine maintenance ensures such drainage provision remains functional. Drainage features are 

tailored to site specific characteristics on each unique segment, within limitations dictated by access needs and 

safety requirements. Every opportunity is considered for minimizing water concentrations and related effects on 

surroundings by treatments that isolate contributing areas, whether on adjoining road segments or different parts 

of the cross section template on the same segment. of the cross section template on the same segment. 

The simplest, most economical, and most effective technique for minimizing water displacement due to the 

typical segment involves addition of surface cross drainage. Here, the total water volume displaced may not be 

reduced much, but it is broken into smaller increments, travels a shorter distance during displacement, and is 

more quickly and easily absorbed into down slope locations, potentially lowering cumulative volume distance 

displacement. Surface cross drains consist of surface shaping and devices designed to capture water that 

collects on, and drains down, the road and release it in a manner that minimizes effects to adjacent areas and the 

watershed (USDA-FS, 1998). Surface shaping includes broad-based (drivable) dips, waterbars, and rolls in profile 

(twist of crown or inslope templates to outslope and back again). Devices include open top or sloĴed culverts 

(USDA-FS, 1995), metal waterbars, and rubber water diverters (USDA-FS, 1998). erters (USDA-FS, 1998). 

Machine Operations (i.e. logging, mining, utility and facility

installations) 

Machine operations would be timed to minimize adverse impacts to other resources. Timing of operations on a 

daily and seasonal basis would include such concerns as sensitive soils, proximity to residences and recreational 

sites/designated trails, cultural resources, and special status plant and animal species. sites/designated trails, cultural resources, and special status plant and animal species. 

Operations would be designed and implemented to minimize the loss of site productivity caused by soil 

compaction, displacement, or erosion. compaction, displacement, or erosion. 

Areas with sensitive soils or ground resources of special concern would be protected by logging with lowimpact harvest techniques such as: designated skid trails; directional felling; boom mounted shears; harvester/ 

forwarders; smaller, more maneuverable or low ground pressure equipment; logging during the dry season 

(between June 1 and October 31); and logging over a protective cover of snow and/or frozen ground. er of snow and/or frozen ground. 

Tractor skidding would normally be limited to slopes of less than 35%. Soil moisture conditions would be 

monitored and operations would be suspended before excessive compaction or displacement occurs. e compaction or displacement occurs. 

Landings would be the minimum size commensurate with safety and equipment requirements. Landing 

locations would be selected outside specified buffer areas for streams, riparian areas, raptor nests, residential 

areas, and other sensitive sites. Landings would be located to avoid creating excessive excavation and sidecast or 

slope stability problems. slope stability problems. 

Previously disturbed areas and existing openings would be used where practicable to establish landing sites. ould be used where practicable to establish landing sites. 

Some key landing sites may be retained and dedicated for future timber harvest operations. est operations. 

Machine slash piling, other than on landings, would be avoided if there are other feasible options available 

such as whole tree or leave-tops-aĴached yarding, lop and scaĴer, or prescribed fire. Where machine piling is 

necessary, it would be accomplished with a crawler tractor or skidder equipped with a brush rake type blade to 

minimize soil displacement and provide soil-free piles. minimize soil displacement and provide soil-free piles. 

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Appendix Appendix F 

Perennial stream crossings would be avoided during operations involving heavy equipment for logging, road 

construction or related activities. construction or related activities. 

Designated trails would be avoided during operations involving heavy equipment for logging, road construction 

or related activities to the maximum extent feasible. If avoidance is not possible, provisions for designating 

crossings, rerouting or temporary closure of designated trails will be made to ensure safety and reduce conflicts. 

Trails damaged during operations would be restored following operations. ould be restored following operations. 

Provide variable width no-cut or modified prescription management zones for perennial streams, springs, seeps, 

wet meadows, and other areas which could substantially affect water quality in perennial waters. 

Where forest productivity is emphasized, landings, temporary roads and primary skid trails would be scarified 

following use. Scarification would be to a depth of at least 12 inches. Mounds and berms would be smoothed to 

the original contour. 

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Upper Deschutes Record of Decision and Resource Management Plan ce Management Plan 

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