Forestry BMPs

OUR GOAL: To Protect Our Waters and Site Productivity Through the Proper Use and Application of Best Management Practices.

(BMPs)

What are BMPs?

BMPs are techniques to conserve and protect our waters from being polluted by surface water runoff as well as protect site productivity.

Most of the BMPs shown in this presentation are taken from this manual. Copies are available online at http://www.michigan.gov/d nr/0,1607,7-153 30301_31154_31261-- ,00.html

Specify silvicultural techniques and logging equipment in Operations Inventory and & timber sale contract specifications that are appropriate to slope, erosion hazard or soil stability and that minimize soil disturbance .

Proper Road Planning

 Minimize the number and length of roads and skid trails  Minimize or eliminate constructing new stream crossings  Minimize site impacts

Planning:

 Identification of soil types and their limitations  Identification of slopes > 10%  Flag and buffer wetlands and riparian management zones  Harvest in appropriate season

Buffer Strips/ Riparian Management Zones

Buffer Strips, also known as Riparian Management Zones, are areas along permanent and intermittent streams and other open water bodies that function in the following ways to protect water quality:

Buffer Strips/RMZ’s

 Trapping sediment, nutrients and chemicals  Shading of Streams

Buffer Strips/RMZ’s

 Source of large woody debris and organic matter for maintaining quality aquatic habitat

Timber Harvesting can be conducted in the Buffer Strip/RMZ but activities must be carefully carried out to insure the Buffer Strip/RMZ can always protect the integrity of the stream or other water body

Specifications which maintain the water quality function

 100 Feet from top of bank with width increasing as slope increases Slope (%) 0-10 10-20 20-30 Width (feet) 100 115 135 30-40 40-50 >50 155 175 No activity

Water Quality Function, cont.

 Sufficient trees left to provide shade and large woody debris

Water Quality Function, cont.

 Less than 10% of soil exposed within zone  No haul roads, landings or equipment storage/maintenance sites within the zone

Additional Buffer Strip Specs

 No wheeled equipment use when soils are saturated to avoid soil compaction  Where significant soil disturbance occurs, stabilize immediately

 Where hauls roads and primary skid trails do occur, use drainage devices outside of the RMZ.  On steep slopes and unstable soils, keep wheeled or tracked equipment out  Do not move slash into the RMZ

Appropriate Equipment

This harvester is an example of the type of logging equipment that is “buffer friendly,” allowing removal of timber while not disturbing the soil within the buffer strip

Forest Roads

Forest Roads

Nationwide, EPA estimates that over 90% of the sediment entering forested streams comes from forest roads Good planning, design, construction and maintenance of forest roads will significantly reduce the amount of sediment entering a stream .

Forest Roads

Goal: Reduce the volume and velocity of water and sediment occurring on roads during and after a rain event by providing for proper drainage of water runoff

Forest Roads

KEY POINTS TO INCLUDE IN DESIGN, LAYOUT OF FOREST ROADS:  Use existing roads whenever possible provided they are properly designed

Forest Roads

 Roads follow contour with grades between 2 10 percent  Grades >10% are less than 300' in length.  Roads having unstable soils have grade < 8%. Grades up to 12% < 150'.

Forest Roads

 Roads crowned for proper drainage, where slope is less than 2%  Roads outsloped where gradient permits (2 10% grade); Where insloped, adequate cross drainage provided

Forest Roads

This figure illustrates that the choice of cross-section for a road or section of a road depends on the drainage needs, soil stability, slope and expected traffic volume

Forest Roads

Diversion ditches, broad base dips or culverts used at appropriate intervals Roads/trails should avoid gullies, seeps, springs, wetlands and poor drainage areas.

Diversion Ditches

Install diversion ditches to drain water into a vegetated area Be sure to drain water before reaching the buffer strip

Cross Drainage Culverts

Cross drainage culverts properly installed and free of debris

Forest Roads

No hauling of timber during “spring breakup,” the time when forest roads are saturated with water and prone to rutting

Closing Roads after

Road Closure

their use is part of a good strategy to prevent erosion Use Road signs, gates or other obstructions, such as stumps, to keep motorized traffic off!

Water Bars and Closure of Roads

Construct Water Bars on closed roads. Seed and mulch where road slope is greater than 4%.

Spacing for Water Bars As shown in this table, spacing for water bars depends on road grade

Seeding Mixtures and Rates for Restoration of Closed Roads, Landings and Skid Trails

BROAD BASED DIPS A broad based dip provides cross drainage on haul roads. It can be used on roads having a gradient of 12% or less and is a substitute for cross drainage pipe culverts

Spacing for Broad-Based Dips

As shown in this table, spacing ranges from 300 feet to 100 feet depending on road grade of the haul road

Landings

Locate away from streams and lakes. Locate on well-drained soils and a site where slopes allow water to drain off landing site

Landings

Seed and mulch the landing area to prevent erosion, as well as providing wildlife habitat

 Use waters bars at prescribed intervals  When climbing steep slopes – skidder operator should break grade by skidding in a zigzag pattern to avoid making gullies

Skid Trails

Water Bar Spacing for Skid Trails

Skid Trails

Ensure that during logging operations skidder operators avoid skidding through gullies, and seeps and other wet areas, such as vernal ponds

Stream Crossings

The quality of stream crossing design and construction determines how “stream friendly” a crossing is…

Stream Crossings

All newly built or renovated stream crossings require a permit issued by the Land and Water Management Division, MDEQ

Stream Crossings

Best method – Cross a stream using a portable bridge creates least disturbance to the stream. Examples: railroad flatcar, wooden bridge, portable folding metal bridge.

Stream Crossings

Here is an example of a portable folding metal bridge

Stream Crossings

A portable wooden bridge…..

Stream Crossings

CULVERT INSTALLATION This is the most common type of stream crossing used in forestry; it also has the most potential to damage a stream as well

Stream Crossings

In addition to meeting all MDEQ permit requirements, the following BMPs are associated with the proper installation of culverts for crossing forested streams……..

Stream Crossings

Use the Hasty Method or other DEQ approved method used to determine culvert size

Stream Crossings

This table shows the relationship between the square footage calculated by the Hasty Method and the diameter of the culvert

Stream Crossings

 Pipe extends at least 2' beyond side slope of road  The diameter of the culvert should be 18" minimum or appropriate for calculated end area

Stream Crossings

The alignment of the culvert pipe should match the slope of and alignment of stream

Stream Crossings

Fill over culvert >= 12" or > than 1/2 diameter of culvert (for culverts >24" diameter)

Use of Rock rip-rap over geotextile at inlet and outlet of culvert

Stream Crossings

Base and sidewall fill properly compacted to prevent water from seeping around and under culvert

Stream Crossings

Road grade should be decreased before reaching 50 feet of stream bank.

The point of crossing should be higher than the approaches.

Stream Crossings

Final design will be determined by DEQ permitting staff and all rules and regulations pertaining to Part 31 Water Resources Protection and Part 301 Inland Lakes and Streams, of the Natural Resources and Environmental Protection Act of 1994.

Other Areas of Concern

FUELING AND MAINTENANCE Must occur outside of the riparian area

Rutting

Rutting occurs when soil strength is not sufficient to support the applied load from vehicle traffic

Rutting Affects:

 Aesthetics  Biology  Hydrology  Site productivity

Rutting: Uplands Compared to Wetlands

 Uplands – Compaction and rutting – Opportunities to restrict impacts to site infrastructure – Options to mitigate rutting impacts (e.g., ripping, grading)  Wetlands – Compression (shallow and deep organics) and rutting – Prevention is the key – Few options for mitigation

What is "Excessive" Rutting?

Excessive Rutting

 Commonly prohibited in contracts  Often prohibited in guidelines  Rarely defined  Two components: Depth of impact Spatial extent of impact

Minnesota Rutting Recommendations

Wetland Roads: Rutting >= 6” deep should not exceed contiguous distances of 300’ in length or 50% of the width of the wetland in the vicinity of the rutting, whichever is less

Minnesota Rutting Recommendations

Skid Trails Upland: Rutting >= 6” deep should not exceed 10% of all skid trails and rutting should not exceed 25’ of any 100’ section.

Wetland: Rutting >= 6” should not exceed contiguous distances of 300’ or <50% of the width of the wetland in the vicinity of rutting, whichever is less.

Forestry BMPs

GOAL: OUR To Protect Our Waters and Site Productivity Through the Proper Use and Application of Best Management Practices