Presentation on theme: "Forestry BMPs OUR GOAL: To Protect Our Waters and Site Productivity Through the Proper Use and Application of Best Management Practices. (BMPs)"— Presentation transcript:
Forestry BMPs OUR GOAL: To Protect Our Waters and Site Productivity Through the Proper Use and Application of Best Management Practices. (BMPs)
BMPs are techniques to conserve and protect our waters from being polluted by surface water runoff as well as protect site productivity. What are BMPs?
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.
Minimize the number and length of roads and skid trails Minimize or eliminate constructing new stream crossings Minimize site impacts Proper Road Planning
Planning: Identification of soil types and their limitations Identification of soil types and their limitations Identification of slopes > 10% Identification of slopes > 10% Flag and buffer wetlands and riparian management zones Flag and buffer wetlands and riparian management zones Harvest in appropriate season 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 Trapping sediment, nutrients and chemicals Shading of Streams Shading of Streams
Source of large woody debris and organic matter for maintaining quality aquatic habitat Source of large woody debris and organic matter for maintaining quality aquatic habitat Buffer Strips/RMZ’s
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 100 Feet from top of bank with width increasing as slope increases Slope (%)Width (feet) 0-10100 10-20115 20-30135 30-40155 40-50175 >50No activity
Water Quality Function, cont. Sufficient trees left to provide shade and large woody debris Sufficient trees left to provide shade and large woody debris
Less than 10% of soil exposed within zone Less than 10% of soil exposed within zone No haul roads, landings or equipment storage/maintenance sites within the zone No haul roads, landings or equipment storage/maintenance sites within the zone Water Quality Function, cont.
Additional Buffer Strip Specs No wheeled equipment use when soils are saturated to avoid soil compaction No wheeled equipment use when soils are saturated to avoid soil compaction Where significant soil disturbance occurs, stabilize immediately Where significant soil disturbance occurs, stabilize immediately
Where hauls roads and primary skid trails do occur, use drainage devices outside of the RMZ. 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 On steep slopes and unstable soils, keep wheeled or tracked equipment out Do not move slash into the RMZ 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
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
Road Closure Closing Roads after 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
Skid Trails 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
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
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 Aesthetics Biology Biology Hydrology Hydrology Site productivity Site productivity
Rutting: Uplands Compared to Wetlands Uplands Uplands –Compaction and rutting –Opportunities to restrict impacts to site infrastructure –Options to mitigate rutting impacts (e.g., ripping, grading) Wetlands Wetlands –Compression (shallow and deep organics) and rutting –Prevention is the key –Few options for mitigation
Excessive Rutting Commonly prohibited in contracts Commonly prohibited in contracts Often prohibited in guidelines Often prohibited in guidelines Rarely defined Rarely defined Two components: Two components: Depth of impact Depth of impact Spatial extent 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 OUR GOAL: To Protect Our Waters and Site Productivity Through the Proper Use and Application of Best Management Practices