Attach 7_BMPs Erosion Control Plan Guidelines -recovery activities.docx

NIEVES-RIVERA, LIZANDRA -FS

12/17/18

EROSION CONTROL PLAN AND PRACTICES FOR EYNF RECOVERY ACTIVITIES

El Yunque National Forest

Forest-wide Erosion Control Plan Guidelines

For Restoration, Maintenance, Constructions and Rehabilitation Activities

January, 2019

Preparers:

Forest Soil Scientist Watershed Program Manager

Reviewed and Recommended by:

Ecosystem Management Team Leader

Ecologist

Forest Engineering

Approved by:

Keenan Adams Forest Supervisor / Deputy

1. Background Erosion control management practices applicable to restoration, rehabilitation, maintenance and other ground disturbance projects are described in the Forest Service 990a Technical Guide – National Best Management Practices for Water Quality Management on National Forest System Lands. It is the Forest Service policy to comply with the applicable forest service plans and guidelines. Some level of passive (hand tools) disturbance activities would require to comply with specific soil erosion control management practices depending on specific site conditions.

The Forest Service National Best Management Practices (BMPs) is the agency’s nonpoint source pollution control program for achieving and documenting water resource protection. The general objectives are to demonstrate the agency’s commitment and performance to the protection (and management) of water quality and its responsibility with other federal, state, water boards entities and the public.

The National Core BMPs provide a foundation for water quality protection of NFS lands and facilitate national BMP monitoring. The ultimate goal is to restore and maintain the integrity of the nation’s waters located within or near the national forests and grasslands.

Using this guidance as well as environmental analysis, watershed specialists (Forest Service Hydrologist and/or Soil Scientist) determined the water quality BMPs applicable to the proposed actions. BMPs are the practices that both the Federal and State water-quality regulatory agencies expect the Forest Service to implement to meet its obligation for complying with applicable water quality laws and standards, and to maintain and improve water quality.

2. Erosion Control Plans Objectives

a. A Forest Service ECP describes in detail the short-term mitigation measures (treatments) to prevent erosion and sedimentation in a site-specific project. A detailed and accurate ECP would allow the US Forest Service (USFS) staff to conduct efficient and meaningful inspections of ground-disturbing projects and would provide a needed foundation to ensure that management requirements and best management practices for addressing resource protection are accurately communicated to implementation and field staff.

b. Project Hydrology, Soils, Geomorphology (geology) BMPs are followed to develop the site –specific project erosion control plan. The ECP provides guidance to project implementation leads in how to effectively implement required BMPs. However, not every activity described in an ECP is required.

c. The project implementation leader, in coordination with a hydrologist or soil scientist, can determine which of the ECP techniques would best fit the needs on the ground. This Erosion Control Plan provide mitigations that could be used and stated as general concepts/mitigations as part of any Environmental Analysis planning process.

d. The objective of an Erosion Control Plan on Forest Service land is to effectively limit and mitigate erosion and sedimentation from any ground-disturbing activities, through planning prior to commencement of project activity, and through project management and administration during project implementation.

e. Ensured that all disturbance-related management requirements and provisions for field revisions or modifications are accurately captured in one comprehensive document for each project or activity.

3. Project Location The El Yunque National Forest Forest wide ECP is a document to assist project implementations on all infrastructures, facilities and transportation areas, recreation sites, upland, watersheds, tributaries, etc. Operations shall be confirmed to lands within the boundaries of the El Yunque National Forest. Such as:

· Roads: EYNF encompasses over 30 miles of roads, 11.27 miles of inventoried, classified National Forest System roads in the Forest transportation inventory. Potential dirt roads to be established for to accomplish research objectives, potential temporary project entrance roads (access roads), any adjacent staging areas and or proposed equipment/parking zones. Some of the roads are: Roads: 186, 191, 930, 988, 9966, 27, 9915, 9938, FR10, FS12

· Trail System: 24 miles of recreational trails (13 open trails), 12 miles of administrative trails any unauthorized or non-forest service trails (i.e. user created trails) or emergency trails. Some of the trails are: Caimitillo Trail, La Coca trail, Big Tree trail, La Mina trail, Trade winds trail, El Toro trail, El Yunque trail, Sabana trail.

· Water Intakes: 34 permitted water intakes areas, other potential existing user’s water intakes not permitted or proposals.

· Watersheds and connected Riparian Management Zones and tributaries: Rio Blanco Watershed, Rio Santiago Watershed, Rio Fajardo Watershed, Rio Pitahaya Watershed, Rio Sabana Watershed, Rio Mameyes Watershed, Rio Espiritu Santo Watershed, Rio Canovanas within Rio Grande de Loiza.

· Any ground disturbance projects within uplands (hillslopes zones) adjacent, within El Yunque National Forest Jurisdictional lands.

The specific location of the worksites and boundaries of the project areas will be provided with each project implementation plan / statement of work (SOW). Each SOW or implementation plan would explained the layout of work such as area for heavy mechanical equipment’s, sections for staging, equipment access, sections for erosion control needs, sections for storm water management, etc.

ECP document is also a resource to be follow and as a reference for third party contractors or other entities (and partners) in charge of restoration projects such as: Power line, water intake and water line infrastructure, after and during state agencies woody or soil debris material, volunteer programs, research activities, etc.

4. Project Description Management requirements/BMPs and related erosion control practices (treatments) will be implemented in conjunction with the proposed actions described in any implementation projects requiring ground disturbances activities (for entrance, constructions, restoration, maintenance, rehabilitation, decommission, and similar activities).

Some level of coordination and agreements will take place within areas in which State or other agencies have jurisdiction of the road prisms and other infrastructures.

Some general project descriptions are:

· Channel restructuring, catchments work, rework trail tread for stabilization, due to resource damage and/or drainages needs such as ditch/cross drains rework. Trail reconstruction, re-route, and blockage.

· clean up and redoing ditch to increase water movement

· drainage ways rework, sediment catchment construction

· Increase ditch size and rework to adequate water accumulation and flow, culvert removal and/or upgrades, dissipaters removal, etc., inclusion or changes of bridges and other stream crossings.

· Hillslopes instability restoration needs, debris material removal

· Changes in trail tread (concrete / pavement); changes, upgrades, reconstruction of road prism areas.

· re-contouring scars, scraping and/or grading of hillslope areas, gabions or rock boulder wall stabilizers constructions, removal of material (uphill or within right of ways). Installations of hillslope mass movement restoration techniques.

· Blading, trenching, digging, excavation, ground surface disturbance and removal, surface leveling, ripping/roughening “decompaction”, and fill material haul and spread

· Herbicide treatment or vegetation (trees) removal near and/or adjacent to water sources.

· Reconstruction and/or removal of material within and near water intakes.

· Re-establish natural contours to avoid channeling or pooling of water.

· Clean up with excavator any woody debris material and sediment material within culvert basins (inlet and outlets).

· Some potential subsoiling (deep tilling/ripping in slopes <20%) within roads, trails and highly compacted areas.

5. Forest wide Erosion Control Plan Enactment Within Ground Disturbance project proposals, project planners and administrators (e.g. contracting officer representative, project lead) are responsible for consulting with a hydrologist, soil scientist and/or ecologist prior to or during project implementation for the need, interpretation, clarification, or adjustment of watershed management requirements and related erosion control practices (treatments).

Upon establishing the need for erosion control practices and storm management all prescribed best management practices (management requirements and related erosion control practices) will be implemented during and following the proposed activity implementation. Some of the suggested practices should be implemented prior, during and/or after project activities and some of the suggested practices can be required on a case by case basis.

Third party contractor would provide base on projects there erosion control practices. This Forest wide plan can be used as a guideline and suggestions to review other erosion control plans without assumptions of a main document.

6. Project Implementation Maps

a) Project proposed activities and/or contractors designs would be display either by map packages, geographic information system features (shapefiles), or google earth features (KML/KMZ) the location of all the proposed erosion control and/or storm management practices.

b) After ECP and/or design review consult with hydrologist/Soil Scientist/Ecologist for the need of flagging pertinent soil and watershed concern areas.

7. Wet Weather Operation Standards and Storm Preparedness Plan WWO management plan should be applicable to all proposed project activities using mechanical equipment (even light pressure equipment) during project implementation.

Operations conducted anytime of the year would cease and all BMPs and erosion control structures would be installed when El Yunque Safety Official and/or the National Weather Service declare unsafe forest conditions and temporary areas closure.

Within the area threshold instability and sediment movement occurs due to storms events with a greater than 2 inches high intensity storm. Upon forest opening the operations and safety department monitored areas; therefore consultation with a soil scientist, geologist or hydrologist is recommended for field observations and any potential erosion control practices upgrades.

Hauling, and heavy equipment traffic within soil/ground surface, after storm events or under high saturation areas may be tolerable when:

1. The haul road from the unit to the paved road is stabilized with sufficient aggregate to support haul under evaluated conditions.

2. Earth surfaced roads are dry enough to be bladed and shaped to maintain proper drainage. This may be necessary quite frequently, depending on road conditions and pending storms.

3. The road is in a condition acceptable for drainage. High seepage (water storage soils) soils are present within the El Yunque National Forest, acceptable drainage on this areas could require more reinforcement of erosion control and storm management practices. Soil surface scraping of these areas.

But should not be allowed when:

· The sub-grade would become saturated and the stability of the road prism cannot support haul.

· The native surfaced cannot be immediately shaped for drainage.

· Sections of roads lose structural strength and would not support haul.

· Sediment can drain from the roadway and enter a stream-course.

Where above events are present, consultation with the Forest Service Engineering department is expected to stabilize any road surface and drainages and to follow road reconstruction and maintenance guidelines.

Depending on the soil profiles, some areas could be plastic for some period within sub-surface horizons but optimal within surface layers. This could occur within areas in which heavy equipment overload high clay content soils. In this case, a soil scientist will provide recommendations to continue operations and/or alternative managements.

Within applicable areas, and as stated bases on a case by case project review, these practices will be in place prior, during and after ground disturbance to control and minimize any runoff and sediment movement within roads prisms and within disturbed areas. The main objective of these practices is to divert runoff into a vegetation zone for filtration and infiltration, with the goal of reducing erosion and sediment or contaminant movement.

Most of these practices should be kept in place to stop and filter runoff until the disturbed areas are stable, with at least 30% effective vegetation or ground cover within low slope areas (0-25%) and 40% within moderate slope areas. This requirement is expected in mechanical disturbed areas and excluded for open recreational use areas, such as trails.

Storm Preparedness plans and seasonal closures are part of current/customary contract packages and review design by specialists. Projects lead by other entities should/would be aware of section 7 through agreements, permits, etc. Above wet weather guidelines are intended as useful strategies to be follow.

8. Maintenance, Inspection, Repair and Monitoring of Best Management Practices

Installation, Maintenance and Repair

For the contract period, the contractor would be responsible for the installation, maintenance, and repair of the BMPs under project lead supervision, following watershed, fisheries, and ecologist review inputs. After contract completion, responsibility would be taken over by the El Yunque National Forest Watershed Crew on a case by case basis.

Inspections The project implementation leader (contract administrator, inspector, etc.), and other forest staff (upon request or designation) such as engineers, hydrologists and soil scientists, geologists, ecologies, fisheries would check BMPs implemented. Effectiveness would be noted and corrective actions would be taken if detrimental impacts to water quality or soil productivity are occurring. Any corrections observed by specialists (designated personnel) would be submitted to contract administrator and/or project lead not to on field project contractors.

9. Contact Information El Yunque National Forest Watershed Personnel Lizandra Nieves- Rivera – Forest Soil Scientist and Watershed Program Management – lnievesrivera@fs.fed.us

10. Summary Best Management Practices and erosion control practices will be planned, implemented, maintained and monitored for each pertinent activity stated in Appendix A. Proper implementation of the prescribed Best Management Practices and this Erosion Control Plan should effectively reduce potential erosion resulting from project implementation.

REFERENCES

Frasier, Jim. 2006. Mechanized Equipment Operations in Riparian Conservation Areas. Stanislaus National Forest, Sonora, California.

USDA, Forest Service. 2003. Low Volume Roads Engineering, Best Management Practices Field Guide. http://www.fs.fed.us/t-d/programs/forest_mgmt/projects/lowvolroads/

USDA Forest Service. 2012. National Best Management Practices for Water Quality Management on National Forest System Lands. Washington Office. Washington D.C. FS-990a

USDA, Forest Service. 1998. North Central Research Station –General Technical Report NC-202 – Temporary Stream and Wetland Crossing Options for Forest Management

USDA, Forest Service. 2008. Technology and Development Program – 0834-2828-MTDC – Using Subsoiling to Reduce Soil Compaction.

USDA Forest Service. 2011. Water Quality Management for Forest Systems Lands in California – Best Management Practices. Pacific Southwest Region, Vallejo, California.

Yee, C.S. and Blakemore, T. 1984. Waterbars – Making Them More Effective. California Forestry Note – 90. State of California, Department of Forestry

APPENDIX A

EROSION CONTROL PRACTICES CLASSIFICATION, AND SPECIFICATIONS

ECP# 1. Preservation of Existing Vegetation Preservation of existing vegetation is the identification and protection of desirable vegetation that provides erosion and sediment control benefits, by protecting the vegetation cover and minimizing the ground disturbed area. It includes the treatments knowns as buffer strips, vegetation buffers, or permanent vegetative cover.

CLASSIFICATION:

FOR ALL DISTURBANCE ACTIVITIES TO REDUCE EROSION AND RUNOFF DIVERSION (FILTRATION)

Practice period: Short term practices during project implementation and long term practices until effective project area stabilization[footnoteRef:1]. [1: Project area stabilization: achieved when erosion control practices are effective in the area, resulting in proper reclamation. ]

Specifications (design, installation, etc.):

a. Identify and delineate in contract documents (maps) and in the field by flagging all vegetation buffer areas (sensitive areas) near water bodies.

b. Delineation should be done prior to the start of soil-disturbing activities.

c. Preservation of vegetation areas often includes steep slopes, watercourse, and other sensitive areas (i.e. avoid disturbance to wetlands).

d. Minimize ground disturbance to the extent feasible during project implementation by locating temporary roadways (access) to avoid stands of trees and shrubs and to follow existing contours to reduce cutting and filling.

e. Limit the size and extent of temporary parking and staging areas, including an infiltration /vegetation area, and locate these in flat areas. Size limitation will depend on: the type and amount of equipment, as well as to keep reasonable turning, off-loading and loading areas. This should be determined on a case by case basis with the goal of minimizing compaction and disturbance to the area.

f. When removing vegetation or disturbing ground surface, consider impacts (increased exposure or wind damage) to the adjacent vegetation that will be preserved.

g. If activity is near water sources, such as pipe systems, consider storm management practices (silt fences, weed free straw bales, etc.) in case of sediment movement during pipe connection to water source.

Specific vegetation buffer requirements within sensitive areas:

a. Recommend to follow ECP# 23 - Mechanized Equipment Operations in Riparian Conservation Areas

ECP# 2. Schedule Develop for every proposed activity a schedule that includes sequencing of disturbance activities with the implementation of management requirements, including the soil stabilization and sediment movement control (erosion control) practices.

CLASSIFICATION:

FOR OPERATIONS SCHEDULED DURING WET/WINTER STORM PERIOD. OPERATION STANDARDS ARE DESIGNED TO REDUCE DETRIMENTAL RESOURCE EFFECTS DURING PROJECT IMPLEMENTATION

Practice period: Short term practices during project implementation and upon completion of project.

Specifications (design, installation, etc.):

All prescribed best management practices (management requirements and related erosion control practices) will be implemented during and following the proposed activity depending on a case by case review.

In general:

a. Do not operate equipment when ground conditions are such that excessive rutting and compaction could occur.

b. Follow the Wet Weather Operation Standards (plan) in section 7 – the plan provided specifications in regards to when to stop operations after rain events, who makes the field evaluations and consultation.

d. Ground disturbing activities within instream areas will be required to be implemented during no or low flow periods. At hydrologist’s (watershed personnel) discretion, instream erosion control treatments and crossing treatments can be applied during the project implementation.

ECP# 3. Riprap /Grouted Riprap and/or Masonry Splash Apron

CLASSIFICATION:

FOR INSTREAM WORK – CULVERT AREAS

AS AN OUTLET PROTECTION/DISSIPATION DEVICES AND/OR TO PREVENT DOWN-CUTTING

Practice period: Short term or long term practices depending on hydrologist and engineering consultation after culvert installation

Specifications (design, installation, etc.):

Riprap – rock blankets: Rock placed on ground surface

· Ideal riprap is a well-graded, durable, large rock, with fractured surfaces, sized to resist scour or movement by water and installed to prevent erosion of native soil material.

· Reduces runoff velocities, encouraging infiltration

· Unstable riprap on steep cut slopes can be a safety hazard.

· Use for steep excavated cuts, particularly on the bank of a stream, may require permanent protection, such as heavy rock riprap.

· Use as an outlet protection - placed at the outlet of pipes or drainage structures to dissipate the energy of flowing water, reduce its flow velocity, and prevent channel or bank scour.

· Riprap rock size, as well as use of other measures, is commonly determined as a function of stream velocity and local channel conditions.

· Riprap maybe be placed over a filter blanket of geotextile or bedding of graded gravel, in a layer 1.5 times (or more) as thick as the largest stone diameter used.

· Ideally riprap should be placed upon a stable foundation and upon a filter layer made either of coarse sand, gravel. The riprap itself should be graded to have a range of sizes that will minimize the voids and form a dense layer.

· At culvert outlets where pipe velocities are accelerated, protect the channel with either a plunge pool (on gentle slopes), rock armoring (riprap) or with a splash apron with a rough or rock inset surface and cutoff key.

ECP# 4. Nonwoven Geotextiles /Erosion Blankets

CLASSIFICATION:

A- FOR STREAM BANK STABILIZATION DURING INSTREAM WORK, CROSSINGS

B- FOR SLOPE STABILITY WITHIN STOCKPILES/ BORROW SITE / STREAM BANKS / ETC.

Practice period: Short term practices during disturbance activities

Nonwoven geotextiles –

· Recommended for use with temporary installations because it is less slippery than woven fabrics, reducing movement of the structure during use. Also, non-woven geotextiles exclude fine particles while allowing water to flow through from above and below. This geotextiles will provide additional support during use, lessen the movement of sediment, and can speed re-vegetation of the site after the structure is removed.

· A non-woven fabric will not continue to tear as a woven fabric may if it becomes punctured. It is important to limit the number of high spots (e.g. rocks, stumps) to reduce the potential of punctures during use of the crossing

· Sometimes, the geotextile may be too heavy with soil and water to be easily recovered in a reusable condition. For this reason, it may be beneficial to use shorter lengths with the ends overlapped

· On very soft soil where the geotextile sinks when it is stepped on, it is best to sew the overlapped area together. If it is not possible to remove the geotextile, a biodegradable fabric should be used such as coconut fiber erosion blankets – see following ECP.

· The geotextile should be removed at the same time as the crossing option.

Geotextile underdrain: usage as a filter blanket below culvert and/or cross drain area.

· Geotextile fabric should be 12 oz. non-woven.

· Drain rock shall be crushed clean aggregate (at least 1 inch)

· At least 1 inches crushed rock for about 6 inches depth above non-woven geotextile.

Erosion blankets –

· Consult a wildlife biologist for restrictions/limitations of erosion control blanket usage.

· Use for immediate surface erosion protection and reduction of erosion by as much as 90 percent.

· Use on sites requiring durable, long-lasting, erosion control beyond anchored or unanchored mulch. Use for erosion control until plant establishment.

· Use on steep slopes and/or erodible soils.

· Soil surface needs to be graded smooth to establish soil contact.

· Typically up to 1.5H: 1V, maybe up to 1H: 1V.

· Due to wildlife entrapment concerns, should use what is considered wildlife-friendly blankets (no synthetic netting material).

· Natural-fiber netting is environmentally preferable; choices include jute and coir (coconut husk fibers), and pine shred (pieces) with one netting side, which are biodegradable.

· To be considered 100% biodegradable (which is the environmentally preferable option), all components of an erosion control blanket (including netting and thread) must be made of natural-fiber materials, but some natural fiber blankets can have plastic netting on one side.

· If a blanket with a straw matrix is used (for example straw-coconut fiber blankets), certified weed-free straw should be used to avoid contributing to the spread of invasive weeds. This option need to be consulted with Forest Ecologist for approval in any project activities.

· Staples will be required for blankets installations. The type of staple depends in the soil cohesiveness, U shape top staples are recommended, and some are biodegradables (proper for environmentally sensitive areas).

· Site preparation, slope and/ or channel installation should be performed in accordance with manufacturer’s installation guidelines.

· Blankets are measured (sold) by the square yard of surface area covered.

Erosion blanket installation photo:

Uphill – coconut fiber erosion blanket and vegetation on toe

ECP# 5. Straw bale Barriers / Silt Fences/ Fiber Rolls/Wood Chip Bags/ Wattles

A- FOR WATER QUALITY, STABILIZE SOIL DISTURBED AREAS (SEDIMENT CONTROL) WITHIN INSTREAM WORK

B- FOR SEDIMENT AND RUNOFF CONTROL AS STORM MANAGEMENT TECHNIQUES

Practice period: Short term practices until area stabilization¹

Specifications (design, installation, etc.):

Straw Bales:

· To reduce overland flow, tamp soil between bale bottom and ground surface.

· Leaves no gaps between bales.

· Stake and entrench straw bales (2 stakes per bales). Drive stakes or lath through the bales so that the stakes are buried 6 to 10 in. (15 to 25 cm) into the soil to firmly anchor them in place.

· Bales should be keyed (buried) around 4 inches deep into the soil.

· Long term structures must be periodically cleaned and maintained.

· This option need to be consulted with Forest Ecologist for approval in any project activities

Silt Fences:

· Appropriate locations are: below the toe of exposed and erodible slopes; down-slope of exposed soil areas; around temporary stockpiles; along streams and channels; along the perimeter of a project.

· To be effective, should be keyed in and trenched. Locate the trench in front of the filter fabric in the overland / runoff direction. Ideal trench depth is 4 inches (10 cm) and 4 inches (10 cm) width.

· Drive wooden stakes or lath spaced 4 to 6 ft. (1.2 to 1.8 m) apart into the ground to hold the geotextile or other permeable fabric silt fencing in place.

· Cut the fabric in long strips that are 2 to 3 ft. (0.6 to 0.9 m) wide. The lower 6 in. (15 cm) of the fabric should form an “L” facing uphill. This should be buried, preferably in a shallow trench, or covered with soil to prevent water from running under the barrier. Pack the soil firmly over this part of the fabric.

· Not intended for use as mid-slope protection on slopes greater than 1:4 (V: H).

· Additional material if use below slopes subject to creep, slumping, or landslides.

· Don’t uses in streams, channels, drain inlets, or anywhere flow is concentrated.

· Don’t use silt fences to divert flow.

· Slope of area draining to silt fence shall be less than 1:1 (V: H).

· Limit to locations suitable for temporary ponding or deposition of sediment.

· Fabric life span generally limited to between five and eight months. Longer periods may require fabric replacement.

· Generally, silt fences shall be used in conjunction with soil stabilization source controls up slope to provide effective erosion and sediment control. Such as: ripraps, long staples, log dams, erosion blanket, etc.

· Excavation of the trenches shall be performed immediately before installation of the temporary linear sediment barriers.

· Where a silt fence is determined to be impractical due to specific site conditions, the silt fence may be constructed at the toe of the slope, but shall be constructed as far from the toe of the slope as practical.

· Inspect silt fence when rain is forecast and following rainfall events.

· Sediment shall be removed when the sediment accumulation reaches one-third (1/3) of the barrier height. Consider incorporating removed sediment in the project sites.

· Remove silt fence when no longer needed

· For slopes adjacent to water bodies or Environmentally Sensitive Areas, additional temporary soil stabilization shall be used such as erosion blankets, wattles, woody materials.

In highly weathered rocks with soil horizons translational sot topples slides – geotextiles could be use as silt fences to retain loose material and sediment movement. Set up of geotextile as silt fences require installation of other erosion control for draining such as riprap outlets and slash/wattles/logs to retain sediment material above culverts Example:

Fiber Rolls (Wood Chip Bags)/Wattles: Use to shorten slope distance, retain sediment, and reduce rill formation. Use for temporary 2-3 year protection until plants are established. Use on gentle or steep slopes (up to 1H: 1V). Requires intimate contact with ground and has limited sediment capture capability. Should not be used on creeping or slumping soils or for high flows. May be ineffective for interrill erosion.

Follow wildlife-friendly references for fiber rolls, wattles, chips bags, etc.

ECP# 6. Temporary Stream Crossing Options

· Fords (Armored Stream Beds), Pole Fords, Portable or On-Site Constructed Bridges

CLASSIFICATION:

FOR SHORT TERM STREAM CROSSINGS WITH OR WITHOUT ADDITIONAL SOIL STABILIZER PRACTICES

Practice period: Short term practices during disturbance activities and upon completion of project

Specifications (design, installation, etc.):

· Input from a licensed engineer into the design of many stream crossing options is recommended.

Ford or Low-Water Crossing:

· A ford or low-water crossing uses the stream bed as part of the road or access trail. They are best suited for short-term, limited traffic. Use should be limited to periods of low flow when the water is less than 2 ft. (0.6 m) deep.

· New fords should be located where the banks are low, less than 4 ft. (1.2 m) high, and gently sloping; where the grade of the approach to the stream does not exceed 5:1 (horizontal to vertical); and where the stream bed is firm rock or gravel.

Armored Stream Beds – Fords:

· Permits and regulatory authorities’ consultation may be required.

· Constructing a firm crossing using gravel or rock is common when the existing bed of an intermittent or perennial stream is too weak to support traffic. When using clean gravel or rock fill to construct a ford, the existing weak material in the stream bed should be excavated first. This allows the natural shape of the stream channel to be maintained, and reduces the problem of the gravel mixing with the mud, making the fill ineffective.

· Use a minimum of 6 in. of gravel or rock fill unless it is not possible to excavate deep enough to accommodate this amount of fill. The gravel or rock fill should not raise the crossing higher than the original stream bed level.

· Lay down a non-woven geotextile before placing gravel or rock fill, as long as it is approved by the appropriate regulatory authorities. This keeps the fill separated from the weak native materials and provides added support to the crossing. Although fords that are constructed with gravel or rock fill are intended as temporary crossings, the gravel or rock fill is not removed when the crossing becomes inactive.

Pole Ford:

· Consult a Hydrologist before implementing.

· A pole or log ford may be established for crossing small streams or wet/unstable sections. For this type of ford, the stream channel is filled with logs laid parallel to the direction of stream flow. This works well for crossings that will be used only a few times and where the logs can be easily removed as soon as the work is completed. It is best suited for dry ditches and intermittent stream channels because of the risk of blocking stream flow.

· Placement of two or more steel cables laid bank-to-bank below the pole ford will facilitate removal of the logs.

· A non-woven geotextile can be placed directly across a stream to create a firm base for the ford. Installation is quick and easy.

· Supplementation with additional logs, gravel, or rock fill may be needed in the weakest portions of the crossing to create a firm base for the ford.

Portable Bridges:

· Bridges keep fill and equipment out of the water body or unstable/wet areas to the greatest degree of any stream crossing option. Designs are available for a wide range of span lengths and load capacities (e.g., pickup trucks, skidders and forwarders, or loaded semi-tractor trailers).

· It is recommended that bridges be installed on abutments on both sides of a stream.

· If the soils within the approaches to the bridge are weak, or if they will be significantly disturbed during installation and use of the bridge, we recommend using corduroy, wood mats, or wood panels (see ECP# 21)

ECP# 7. Berm / Earth Dikes Including Ground Cover such as Woody Material and Storm Management Controls

A- FOR RUNOFF FILTRATION OR DIVERSION IN ADJACENT AREAS WITHIN STREAM CROSSINGS AND/OR INSTREAM WORK (WITHIN ROADS OR TRAIL WORK)

Practice period: Short term practices during disturbance activities and upon completion of project

· These are structures that intercept, divert and convey surface runoff, generally sheet flow, to prevent erosion.

· Earth dikes/drainage swales may be used: below steep grades where runoff begins to concentrate, along roadways and facility improvements subject to flood drainage, at the top of slopes to divert run-on from adjacent or undisturbed slopes, and/or at the bottom and mid-slope locations to intercept sheet flow and convey concentrated flows.

· Are not suitable as sediment trapping devices.

· Compact any fills to prevent unequal settlement.

· Excessively steep, unlined dikes and swales are subject to erosion and gully formation.

· Inspect temporary measures prior to the rainy season, after rainfall events, and regularly (approximately once per week) during the rainy season.

· Inspect ditches and berms for washouts. Replace lost riprap, damaged linings or soil stabilizers as needed.

· Inspect channel linings, embankments, and beds of ditches and berms for erosion and accumulation of debris and sediment.

· Temporary conveyances shall be completely removed as soon as the surrounding drainage area has been stabilized, or at the completion of construction.

ECP# 8. Brush or Log Fences / Willow Fences

CLASSIFICATION:

FOR STREAM BANK STABILIZATION AND SLOPE STABILIZATION

Practice period: long term practices as part of the disturbance activities and upon reclamation.

Specifications (design, installation, etc.):

· Catches sediment and raveling material

· Use on steep cut slopes or landslide scarps.

· Use on stable slopes up to 1.3H: 1V.

· Use for raveling and eroding material with moist conditions.

· Use for fine texture soils that are wet during the growing season. May not be suitable for dense or very coarse material.

· Requires moisture for fence to grow.

· May require significant plant material.

· May be labor intensive.

· Pushed barrier constructed of small brush and limbs to the ground at the toe of the fill slope.

· Bury brush fences at least 4 inches deep (10 cm) into soil.

ECP# 9. Rolling Dips - Cross Drains

TO DIVERT RUNOFF TO STABLE (FILTRATION) AREAS AS STORM MANAGEMENT TREATMENT

Practice period: long term practices as part of the disturbance activities and upon reclamation.

· Follow engineering management for rolling dips/ cross drains construction.

· Use rolling dips (broad-based dips) / cross-drains to move water off the road surface efficiently and economically, without the use of culvert pipes.

Recommended Maximum Distance (feet) Between Rolling Dips Based in Soil Erosion Potential

· Typically for low volume, low speed roads with grades less than 12%.

· Construct rolling dips deep to provide adequate drainage. In soft soils, consider armoring the mound and dip with gravel or rock, as well as the outlet of the dip.

· Cross drains can also function as French drainages when cover with geotextiles or blankets, top with gravel material.

ECP # 10. Cross Ditches (drains) and Swales (into vegetation areas)

CLASSIFICATION:

FOR RUNOFF DIVERSION AS STORM MANAGEMENT TREATMENT

Practice period: long term practices as part of the disturbance activities and upon reclamation.

Specifications (design, installation, etc.):

· Stabilize inlets, outlets and slopes.

· Properly compact the subgrade.

· Stabilize cover when needed.

· Use in 2:1 slope ratio or flatter

· Use rock as water dissipaters or sediment entrapment were applicable

· Lead-off ditch – bottom should be sloped to provide proper drainage

· Graded swales – contractor shall construct lead off ditches and needed to ensure proper drainage of Swale. Lead-off ditches are incidental to the construction of graded swale

· Graded (rock swale) Swale –

· At least 50 ft. wide (each side from center 25 feet wide).

· Center of Swale at least 5 inches of rock deep armoring material (depth)

ECP# 11. Gravel (crushed rock) Surface / Armoring

A- FOR MINIMIZING RUTTING, COMPACTION, EROSION, AND RUNOFF AS NEED IN STAGING, PARKING, AND PROJECT AREAS.

B- AS A TEMPORARY STORM MANAGEMENT PRACTICES IN FLAT AREAS.

Practice period: long term practices to reduce soil movement (erosion and runoff) in not decommission traffic areas and/or crossings.

Specifications (design, installation, etc.):

· Important – Consult and follow engineering department specifications for aggregate addition to roadway surface (to minimize rutting) or any traffic (temporary road access) areas. Size of rock and percent of rocks distribution effective for activities within the area.

· In situations where ruts are occurring without wet conditions, locate new adequate access areas.

· In the case of no additional access routes –consult with soil scientist and/or engineering to observe surface bearing load (strength) conditions to consider effective application of crushed rock (aggregates). Assess conditions if ruts get within 2 - 4 inches and stop operations and traffic within areas if ruts get deeper than 4 inches.

· The roadway surfacing aggregate must perform two basic functions. It must have high enough quality and be thick enough to provide structural support to the traffic and prevent rutting, and it must be well graded and mixed with sufficient fines, preferably with some plasticity, to prevent raveling and wash boarding.

· Avoid using surfacing materials that are fine grain soils, soft rock that will degrade to fine sediment, or clean, poorly graded coarse rock that will erode, ravel, or washboard. Ideally use a well graded material to achieve maximum density.

· In extremely wet areas consider using swamp mats, pressure mats, corduroys and low pressure equipment.

· If adequate, consider using drainage control such as geotextiles, water bars, rolling dips.

ECP# 12. Exclusion zones within Riparian Management Zones

FOR MECHANICAL EQUIPMENT WORK SUCH AS SKIDDING, PILING, SITE PREPARATION FOR PLANTING, BURNING, SHREDDING, HAULING, ETC.

· The riparian management zones are defined in these alternatives as 100 feet from the edges unless a site-specific analysis is conducted to identify and delineate a more specific riparian management zone. Standards and guidelines require the use of best management practices approved by the Forest Service for all management activities or maintenance practices proposed close to riparian areas.

· Protective measures for riparian areas include the delineation of riparian management zones on perennial and intermittent streams. Management activities within the riparian management zone must comply with the best management practices and any other water quality regulations.

· No management practice that may cause detrimental changes in water quality and chemical composition, block the watercourse, or deposit sediment that adversely affects the water conditions and fish habitat, shall be permitted within the riparian management zone.

· Ensure Forest Service soil and water best management practices are implemented when management or maintenance activities are conducted near riparian areas.

Mechanized equipment:

· Mechanical equipment usage could be excluded or limited within RMZ depending on Management Areas.

· Soil Strength – Operate only when 90% of the total tracked area is rutted less than 4 inches deep. Rutting depth is measured from the top of the undisturbed litter/duff layer to the top of the duff in the rut (“duff-to-duff”).

· Soil Cover – Operate only when continuous ground cover is retained in 90% of the total tracked area.

· Stream course Debris – Remove operation-created debris from stream channels.

· Vegetation – Retain obligate riparian shrubs and trees (i.e., willows, alders, aspens).

· Stream banks – Do not damage stream banks with equipment, and retain sufficient vegetation to maintain stream bank stability.

Operations Adjacent to Special Aquatic Features Special aquatic features include lakes, wet meadows, bogs, fens, wetlands, springs, seeps, stream beds.

Exclusion Zone:

· Consult with watershed specialists (hydrologist, soil scientist and/or ecologist in regards to location of above sensitive areas and width or buffers of exclusion zones.

· Create a buffer following an exclusion zone (buffer zone). No mechanical equipment should be near the channel and should only be crossing at existing crossing or other sites CLEARLY identified.

ECP# 13. Waterbars

CLASSIFICATION:

A- FOR ROUTE DECOMMISSIONING TO REDUCE EROSION AND IMPROVE RUNOFF FILTRATION.

B- FOR REDUCING SEDIMENT MOVEMENT WITHIN HILLSLOPE DISTURBED AREAS (GENTLE TO MODERATE SLOPE PERCENT’S)

Practice period: long term practices as part of the disturbance activities and upon reclamation.

Specifications (design, installation, etc.):

· Waterbars are designed to intercept slopes, slow, and then spread the overland flow of precipitation in order to reduce soil erosion and sediment transportation. The concept is to direct water off disturbed areas (areas that are typically compacted and have low amounts of soil cover) before it can build up enough energy to move and transport soil and sediment into filtration - vegetation zones (within gentle slopes).

· Within EYNF waterbars would applicable within dirt roads areas or potentially in gentle to moderate hillslopes (mostly hand tools created waterbars) presenting disturbance features.

· Before recommending or suggesting waterbars within any projects review and inputs from EYNF engineering, recreational and watershed specialists is needed.

· Within EYNF waterbars can also be use as temporary erosion control (water and sediment dissipaters and catchments) during trails, roads construction when the area is obliterated (pavement/concretes) and project implementation over dirt/ground surface.

Installation of waterbars (within non paved roads, or temporary open disturbed (bare) soil areas) should occur as described in the below specifications.

· Spacing: These spacing distances should be used as a guide. Judgment should be used in locating waterbars to minimize erosion potential. Install waterbars at the following recommended intervals:

Recommended Spacing for Waterbars on Roads (non-paved) Percent Skid Trail Gradient(A)

Erosion Hazard Rating for the Area(B)

(Spacing is in feet)

(A) These are guidelines and are not intended to restrict the implementation of more or less waterbars if the need or lack of need is justified.

(B) Erosion Hazard Ratings (EHR) is based on general area around road or trail and not on the bare area of the road or trail.

(C) Areas of high soil burn severity and high vegetation burn severity should use the very high Erosion Hazard Rating.

· May require hand work instead of mechanical equipment.

· Location: Water should be directed to resistant surfaces with high vegetative cover when possible. Waterbars should discharge into undisturbed areas and preferably rocky ground or filter areas well protected with ground and vegetative cover, whether rocks or organic materials. Waterbars should not direct water into stream channels.

· Depth and Width: Waterbars need to be cut into surface, do not simply push up soil. Waterbar depths should be at least 6 inches; total height from bottom of ditch to the top of the waterbar should average at least 18 inches and not exceed 24 inches. The width of the waterbar channel should be enough to handle expected water flows and to avoid plugging when a normal amount of sloughing or sediment movement occurs. Higher waterbars do not necessarily mean better waterbars.

The outflow of the waterbar should be as wide as feasible to prevent deposited sediment from blocking water flow. Small storm events would often move sediment and vegetative litter into the outlets of waterbars. Over time these small events obstruct the outflow and prevent waterbars from working properly in larger storm events.

· Angle: Waterbars should be placed at an angle relative to the road or skid trail. The angle should be directed downhill into vegetation or slash and between 30 to 60 degrees relative to the road or skid trail. Angle is important, if the angle is too shallow, the water would slow down and deposit the sediment it carries in the waterbar. This accumulation would allow the waterbar to be filled and overtop with water making the waterbar ineffective. If the angle is too steep, water would continue at high velocity and be able to erode where it exits the waterbar and erode and carry additional sediment.

Diagram of Proper Waterbar Design

· Timing: At the minimum, waterbars should be installed prior to damaging storm events.

Monitoring Erosion Control Structures During inspections, nonfunctioning waterbars should be corrected and additional waterbars or other erosion control structures should be installed if rill erosion is significant or impacting water quality.

If significant issues are observed, a soil scientist or hydrologist should be consulted for possible addition treatment, which could include the placement of soil cover or other rehabilitation. Questions or concerns, contact local soil scientist or hydrologist.

ECP# 14. Mulching

· Wood (shreds)

· Wood Straw

· Chips

· Wood Mulch

A- FOR SOIL STABILIZATION TO STOP SEDIMENT MOVEMENT, REDUCE EROSION AND TO IMPROVE SOIL PRODUCTIVITY FOR EFFECTIVE RECLAMATION.

Practice period: long term practices as a reclamation technique; a short term practice to reduce soil movement (erosion and runoff) in disturbed areas.

· Wood - Hardwood bark is effective due to its weight and interlocking fibers.

· Wood Straw® is a commercial engineered erosion control mulch product. Use and application level will depend on project funding. See company specifications for percent of cover equivalence. For example, one acre with slopes > 33% and a goal of 70% soil coverage will require 276 bales (regular size).

· Wood chips or shreds will reduce wind and water erosion.

· Wood mulch should not be spread continuously to a depth greater than 3 inches, as it may reduce vegetation establishment if applied too thick. Onsite shredded small trees (6 inch) are effective and plentiful in areas being thinned. Wood mulch may easily be washed or blown away, especially on steep slopes.

· Usage of mulch with ponding/saturated areas should be temporary and replace with gravel (aggregate material) for long term effectiveness.

In General:

· Apply mulch before active runoff, weed growth, or dry conditions for best results.

· Ensure that mulch is uniformly distributed at desired rate and depth for effectiveness.

· Use of too much mulch may kill seeds and prevent growth from heat generated during decomposition.

· Use higher mulch rates (content) but lower thickness for erosion control of silts and clays than sands.

· Apply seed before wood mulch on dry sites to help establish vegetation.

· Chipping (chips) – when using chips, depth of material should not exceed 3 inches and should not exceed 40% ground cover of an area for any given acre.

ECP# 15. Woody Debris / Slash (ground cover)

CLASSIFICATION:

A- FOR MECHANICAL EQUIPMENT WORK SUCH AS SKIDDING, PILING, SITE PREPARATION FOR PLANTING, BURNING, SHREDDING, HAULING, ETC.

B- FOR SOIL PRODUCTIVITY IMPROVEMENT

Practice period: long term practices as a reclamation technique; a short term practice to reduce soil movement (erosion and runoff) in disturbed areas.

· Ensure the material is not stacked and has as much ground contact as practical. A minimum 50 percent effective ground cover is desired but may be limited by vegetation productivity and diversity objectives.

· If present, maintain a well distributed soil cover of 50% on moderate slopes of less than 25%, and 60% cover on steeper slopes in Riparian Conversation Areas. Soil cover consists of unburned duff and needle fall, basal live plant cover, fine woody debris, and downed logs as well as surface rock cover.

· To the extent practicable, drop and lop slash or provide other organic mulch (weed-free straw, wood chips, or other equal) in areas deficient of soil cover to protect soil from detrimental erosion and in large areas of displaced soil. Ensure added organic cover does not exceed vegetation productivity and diversity objectives.

· Ensure that the material is well mashed onto the ground.

· Hand crews should be use in steep toes slopes near…