BEST MANAGEMENT PRACTICE (BMP) BASICS BMP Basics provides a description of agricultural, urban, mixed open, resource, and septic system best management practices that are credited in the Chesapeake Bay Watershed Model (Phase 4.3). For each BMP, BMP Basics provides a description, a photograph, and, where appropriate, a short list of examples. The nitrogen, phosphorus, and sediment pollutant removal efficiencies for each BMP can be found at http://www.chesapeakebay.net/pubs/waterqualitycriteria/CBWS model BMP.doc. Additional tributary strategy tools and information can be found on the web site at www, chesapeakebay. net/tribtools. htm ------- AGRICULTURAL BMPs BMP: Conservation Tillage Description: Conservation tillage involves planting and growing crops with minimal disturbance of the surface soil. Conservation tillage requires two components, (a) a minimum 30% residue coverage at the time of planting and (b) a non-inversion tillage method. No-till farming is a form of conservation tillage in which the crop is seeded directly into vegetative cover or crop residue with little disturbance of the surface soil. Minimum tillage farming involves some disturbance of the soil, but uses tillage equipment that leaves much of the vegetation cover or crop residue on the surface.6 Source: USDA, NRCS ------- BMP: Riparian Forest Buffers (Agriculture) Description: Agricultural riparian forest buffers are linear wooded areas along rivers, stream and shorelines. Forest buffers help filter nutrients, sediments and other pollutants from runoff as well as remove nutrients from groundwater. The recommended buffer width for riparian forest buffers (agriculture) is 100 feet, with a 35 feet minimum width required.6 Source: USDA. NRCS ------- BMP: Riparian Grass Buffers (Agriculture) Description: Agricultural riparian grass buffers are linear strips of grass or other non-woody vegetation maintained between the edge of fields and streams, rivers or tidal waters that help filter nutrients, sediment and other pollutant from runoff. The recommended buffer width for riparian forests buffers (agriculture) is 100 feet, with a 35 feet minimum width required.6 ------- BMP: Wetland Restoration (Agriculture) Description: Agricultural wetland restoration activities re-establish the natural hydraulic condition in a field that existed prior to the installation of subsurface or surface drainage. Projects may include restoration, creation and enhancement acreage. Restored wetlands may be any wetland classification including forested, scrub-shrub or emergent marsh.13 Source: USDA, NRCS ------- Land Retirement (Agriculture) Agricultural land retirement takes marginal and highly erosive cropland out of production by planting permanent vegetative cover such as shrubs, grasses, and/or trees. Agricultural agencies have a program to assist farmers in land retirement procedures. Land retired and planted to trees is reported under "Tree Planting".6 ------- BMP: Description: Examples: Tree Planting (Row Crop) The tree planting (row crop) BMP includes any tree planting on agricultural lands, except those used to establish riparian forest buffers, targeting lands that are highly erodible or identified as critical resource areas. Tree planting is also called afforestation because it involves growing trees and converting the land use from agricultural to forest. This BMP results in a landuse conversion from row crop to forest. It is assumed that the density of the plantings is sufficient to produce a forest like condition over time.3,6 Conservation Reserve Program land, converted from row crop to forest. Source: USDA, NRCS ------- BMP: Nutrient Management Plan Implementation (Crop) Description: Nutrient management plan (NMP) implementation (crop) is a comprehensive plan that describes the optimum use of nutrients to minimize nutrient loss while maintaining yield. A NMP details the type, rate, timing, and placement of nutrients for each crop. Soil, plant tissue, manure and/or sludge tests are used to assure optimal application rates. Plans should be revised every 2 to 3 years.6 Source: USDA, NRCS ------- BMP: Description: Examples: Cereal Cover Crops Cereal cover crops reduce erosion and the leaching of nutrients to groundwater by maintaining a vegetative cover on cropland and holding nutrients within the root zone. This practice involves the planting and growing of cereal crops (non-harvested) with minimal disturbance of the surface soil. The crop is seeded directly into vegetative cover or crop residue with little disturbance of the surface soil. These crops capture or "trap" nitrogen in their tissues as they grow. By timing the cover crop bum or plow-down in spring, the trapped nitrogen can be released and used by the following crop.5 Early and Late Season Cover Crops: Early: To be eligible for level 1-reduction credits, the cover crop must be planted earlier than 7 days prior to the long-term published average date of the first killing frost in the fall. Late: To be eligible for level 2-reduction credit, the cover crop must be planted within 7 days after the long-term published average date of the first killing frost in the fall. Source: USDA, NRCS ------- Commodity Cover Crops Commodity cover crops differ from cereal cover crops in that they may be harvested for grain, hay or silage and they may receive nutrient applications, but only after March 1 of the spring following their establishment. The intent of the practice is to modify normal small grain production practices by eliminating fall and winter fertilization so that crops function similarly to cover crops by scavenging available soil nitrogen for part of their production cycle. This practice can encourage planting of more acreage of cereal grains by providing farmers with the flexibility of planting an inexpensive crop in the fall and delaying the decision to either kill or harvest the crop based on crop prices, silage needs, weather conditions, etc." ------- BMP: Conservation Plans Conservation plans are reported as total acres or on a specified landuse. The following landuse categories are associated with Conservation Planning. Farm Plans on Conventional Till Farm Plans on Conservation Till Farm Plans on Hay Farm Plans on Pasture Description: Farm conservation plans are a combination of agronomic, management and engineered practices that protect and improve soil productivity and water quality, and to prevent deterioration of natural resources on all or part of a farm. Plans may be prepared by staff working in conservation districts, natural resource conservation field offices or a certified private consultant. In all cases the plan must meet technical standards.5 Source: USDA, NRCS ------- Animal Waste Management Systems Animal waste management systems are practices designed for proper handling, storage, and utilization of wastes generated from confined animal operations and include a means of collecting, scraping or washing wastes and contaminated runoff from confinement areas into appropriate waste storage structures. Lagoons, ponds, or steel or concrete tanks are used for the treatment and/or storage of liquid wastes. Storage sheds or pits are common storage structures for solid wastes. Controlling runoff from roofs, feedlots and "loafing" areas are an integral part of these systems.5 Lagoons, ponds, steel tanks and storage sheds ------- BMP: Phytase Feed Additives Description: Phytase can be injected into poultry feeds by the integrator or other feed suppliers. Manure phosphorous reductions occur because less phosphorous needs to be blended into feed rations, resulting in a phosphorous source reduction. A reduction up to approximately 30% in manure phosphorus may be possible under optimum conditions.2 ------- BMP: Yield Reserve Description: Yield reserve is a reduction in nitrogen applied to cropland beyond the nutrient management recommendation. The reduction percentage is currently defined at 15%. Based on research, the nutrient management rates of nitrogen application are set approximately 35% higher than what a crop needs to ensure nitrogen availability under optimal growing conditions. In a yield reserve program, the farmer wouid reduce the nitrogen application rate by 15%. An incentive or crop insurance is used to cover the risk of yield loss.2 Source: USDA, NRCS ------- BMP: Description: Examples: Alternative Uses Of Manure/Manure Transport Alternative uses of manure/manure transport is the practice of reducing or eliminating excess nutrient applications within the Chesapeake Bay by either transporting the manure outside of the Chesapeake Bay watershed or finding an alternative use for the excess manure. Excess manure is defined as manure nutrients produced within an area that exceeds the recommended application rates associated with the crops grown.3 Fertilization of commercial tree plantations, research and development of new fuel technologies, peptizing for fertilizer, transport out of the watershed to other areas that need it, and electric generation. Source: USDA. NRCS ------- BMP: Stream Protection With Fencing With Off Stream Watering Description: Stream protection with fencing with off stream watering incorporates both alternative watering and installation of fencing that involves narrow strips of land along streams to exclude livestock. The fenced areas may be planted with trees or grass, but are typically not wide enough to provide the benefits of buffers. The implementation of stream fencing should substantially limit livestock access to streams, but can allow for the use of limited hardened crossing areas where necessary to accommodate access to additional pastures or for livestock watering." Examples: Stream fencing, alternative water sources, stream crossings ------- BMP: Description: Examples: Off Stream Watering In Pasture Without Fencing Off stream watering in pasture without fencing requires the use of alternative drinking water troughs or tanks away from streams. The BMP may also include options to provide shade for livestock away from streams. Limited research has been conducted for this practice that documents changes In livestock behavior resulting in significantly less time spent near streambanks and in streams. The net effectiveness of the practice must reflect partial removal of livestock from near stream areas and relocation of animal waste deposition areas and heavy traffic areas surrounding water sources to more upland locations.^ Alternative water sources, tree plantings away from the stream, stream crossings Source: USDA, NRCS ------- BMP: Off Stream Watering With Stream Fencing And Rotational Grazing (Pasture) Description: Off stream watering with stream fencing and rotational grazing (pasture) combines stream fencing and alternative watering with cross fencing systems to create paddocks to enable rapid grazing of small areas in sequence. Once an area is intensively grazed of most vegetative matter, the animals are moved to another paddock to enable recovery of the pasture grasses. This BMP is beneficial in removing animals from stream areas, but may be offset by an increased animal stocking rate per acre. This increases the concentration of animal manure per acre and may adversely impact the quality of surface water runoff." Examples: Managing forage height through mechanical means, stocking rates, supplemental feeding and other methods Source: USDA, NRCS ------- URBAN AND MIXED OPEN BMPs BMP: Description: Examples: Wetponds arid Wetlands Wetponds and wetland practices collect and increase the settling of pollutants and protect downstream channels from frequent storm events. Wetponds retain a permanent pool of water. Wetpond, wet extended detention pond, retention pond and constructed wetlands Source: MDE Water Management Administration ------- BMP: Description: Examples: Dry Detention Ponds and Hydrodynamic Structure Dry detention ponds and hydrodynamic structure practices are used to moderate flows and remain dry between storm events. These are storm water design features that provide a gradual release of water in order to increase the settling of pollutants and protect downstream channels from frequent storm events. A variety of products for these storm water inlets known as swirl separators, or hydrodynamic structures, are modifications of the traditional oil- grit separator and include an internal component that creates a swirling motion as storm water flows through a cylindrical chamber. These designs allow sediment to settle out as storm water moves in this swirling path. Additional compartments or chambers are sometimes present to trap oil and otherfloatables.6 Dry pond, underground dry detention facility Source: MDE Water Management Administration ------- BMP: Description: Examples: Dry Extended Detention Ponds Dry extended detention ponds are storm water design features that provide a gradual release of a specific volume of water in order to increase the settling of pollutants and protect downstream channels from frequent storm events. Dry extended detention ponds are often designed with small pools at the inlet and outlet of the pond. These BMPs can also be used to provide flood control by including additional detention storage above the extended detention level.6 Dry extended detention pond, extended detention basin and enhanced extended detention Source: MDE Water Management Administration ------- BMP: Description: Infiltration Practices Infiltration practices are used to capture and temporarily store the water quality volume before allowing it to infiltrate into the soil, promoting pollutant treatment and groundwater recharge.6 Examples: Infiltration trench, infiltration basin, porous pavement Source: MDE Water Management Administration ------- BMP: Description: Filtering Practices Filtering Practices capture and temporarily store the water quality volume and pass it through a filter of sand, organic matter and vegetation, promoting pollutant treatment and recharge. Examples: Surface sand filter, swale, bioretention areas (raingardens) Source: Mike Herrmann ------- BMP: Description: Examples: Impervious Surface Reduction Impervious surface reduction includes practices that reduce the total area of impervious cover and practices that capture storm water and divert it to pervious areas, subsequently encouraging storm water infiltration. Natural area conservation, disconnection of rooftop runoff, rain barrels Source: www.composters.com Source: Unknown ------- BMP: Stream Restoration in Urban Areas Description: Stream restoration in urban areas is used to restore the urban stream ecosystem by restoring the natural hydrology and landscape of a stream. Stream restoration in urban areas is used to help improve habitat and water quality conditions in degraded streams. Typically, streams in need of restoring have watershed conditions that have destabilized the stream channel and eroded stream banks. The objectives for stream restoration in urban areas include, but are not limited to, reducing stream channel erosion, promoting physical channel stability, reducing the transport of pollutants downstream, and working towards a stable habitat with a self-sustaining, diverse aquatic community. Stream restoration activities in urban areas should result in a stable stream channel that experiences no net aggradation or degradation over time.4 Source: Harrington and Hoyle Ltd., Landscape Architects ------- BMP: Description: Examples: Erosion and Sediment Control Erosion and sediment control practices protect water resources from sediment pollution and increases in runoff associated with land development activities. By retaining soil on-site, sediment and attached nutrients are prevented from leaving disturbed areas and polluting streams.6 Silt fence, slope drain, permanent vegetation Source: Photo Courtesy of Mike Herrmann ------- BMP: Description: Examples: Nutrient Management (Urban) Urban nutrient management involves the reduction of fertilizer to grass lawns and other urban areas. The implementation of urban nutrient management is based on public education and awareness, targeting suburban residences and businesses, with emphasis on reducing excessive fertilizer use.D Public notices on fertilizer bags, community brochures on fertilizer use Source: Photo Courtesy of MDE Water Management Administration ------- Forest Conservation (Urban) Urban forest conservation applies only to Maryland at this time. This BMP in Maryland is the implementation of the Maryland Forest Conservation Act that requires developers to maintain at least 20% of a development site in trees (forest condition). This is actually a preventative type of BMP which alters the rate of urban conversion. The acreage is calculated from the annual urban increase (population based). The 20% is specific to the Maryland Act and could be different for each jurisdiction or various locations within a jurisdiction.0 Use of assessments, conservation easements, purchase or transfer of development rights, ordinances, and acquisition programs ------- BMP: Description: Examples: Riparian Forest Buffers (Urban) Urban riparian forest buffers are linear strips of maintained woody vegetation that buffer streams, rivers or tidal waters from urban and suburban activity. Forest buffers help filter nutrients, sediments and other pollutants from runoff, as well as remove nutrients from groundwater. The recommended width for riparian forest buffers (urban) is 50 feet with a 35 feet minimum. "6 Buffer strips Source: MD DNR, Forest Service ------- BMP: Riparian Forest Buffers (Mixed Open) Description: Mixed open is a combination of low intensity development, recreation areas, battlefields, golf courses, school recreation areas and other large tracts of herbaceous lands that are not easily associated with impervious acres, but are clearly not available as, or associated with, agricultural land. Mixed open riparian forest buffers are areas of trees usually accompanied by other vegetation, that are adjacent to a body of water and which: maintain the integrity of stream channels; reduce the impact of upland pollution sources by trapping, filtering, and converting sediments, nutrients, and other chemicals; and supply food, cover, and thermal protection to fish and other wildlife. The recommended width for riparian forest buffers (mixed open) is 100 feet with a 35 feet minimum.13 ------- BMP: Tree Planting (Mixed Open) Description: Mixed open is a combination of low intensity development, recreation areas, battlefields, golf courses, school recreation areas and other large tracts of herbaceous lands that are not easily associated with impervious acres, but are clearly not available as, or associated with, agricultural land. Mixed open tree planting includes any tree plantings on any site except those along rivers and streams, which are considered forested buffers and are treated differently. The definition of tree planting does not include reforestation.3 Source: Joseph Murray ------- BMP: Tree Planting (Urban) Description: Urban tree planting is planting trees on urban pervious areas at a rate that would produce a forest-like condition over time. The intent of the planting is to eventually convert the urban area to forest. If the trees are planted as part of the urban landscape, with no intention to covert the area to forest, then this would not count as urban tree planting."3 HMHB1 Source: Joseph Murray ------- BMP: Description: Examples: Nutrient Management (Mixed Open) Mixed open is a combination of low intensity development, recreation areas, battlefields, golf courses, school recreation areas and other large tracts of herbaceous lands that are not easily associated with impervious acres, but are clearly not available as, or associated with, agricultural land. Mixed open nutrient management involves the reduction of fertilizer to non-agriculture, herbaceous areas. Implementation of mixed open nutrient management is based on public education and awareness, with emphasis on reducing excessive fertilizer use in areas including, but not limited to, golf courses and large institutional grounds.3 Nutrient management on golf courses, playing fields and/or rights of way. Source: Civil War Battlefields, http://www.cwbattlefields.com/marvland.html ------- BMP: Description: Examples: Abandoned Mine Reclamation Abandoned mine reclamation stabilizes the soil on lands mined for coal or affected by mining, such as wastebanks, coal processing, or other coal mining processes Land grading, re-vegetation, tree planting, wetland development and the installation of surface water control measures such as diversions, waterways, and retention ponds BEFORE AFTER Source: Office of Surface Mining ------- RESOURCE BMPS BMP: Forest Harvesting Practices Description: Forest harvesting practices are a suite of BMPs that minimize the environmental impacts of road building, log removal, site preparation and forest management. These practices help reduce suspended sediments and associated nutrients that can result from forest operations. Examples: Innovative road design, bridged stream crossings, preservation of stream and wetland buffers, soil stabilization, water bars, logging mats, road surfacing, broad-based dips and avoiding operations when very wet.6 Source: US Forest Service ------- BMP: Description: Examples: Structural Tidal Shoreline Erosion Control Structural tidal shoreline erosion control is designed to protect eroding shorelines by armoring the shoreline to dissipate incoming wave energy while protecting unconsolidated bank sediments. These practices are applicable in areas of higher erosion rates or where wave energy is too strong for vegetation alternatives. These projects are rigid, barrier-type structures that result in a "hardening" of the shoreline to protect against the action of waves, currents, tides, wind driven water, runoff storms, and/or groundwater seepage that erodes shorelines.0 Bulkheads (timber or metal), concrete or masonry walls, stone revetments, stone reinforcements, stone breakwaters, jetties and groins. Source: Torn Darden ------- BMP: Non-Structural Tidal Shoreline Erosion Control Description: Non-structural tidal shoreline erosion control projects are bioengineering techniques that create vegetated wetlands for protection of the shoreline. The controls are designed to protect eroding shorelines by creating vegetated wetlands, which dissipate incoming wave energy while protecting unconsolidated bank sediments. A transition zone is created between the erodible uplands and open water. These wetlands help prevent nutrient- laden sediments from entering the waters,b Examples: Non-structural projects consist of placing clean sandy fill in the intertidal zone and planting the area with native marsh grasses such as smooth cordgrass and saltmeadow hay. Placement of some stone may also be necessary to protect the newly created fringe marsh. Non-structural projects are designed to create shallow water habitat for aquatic species and waterfowl. They also promote water quality by filtering upland runoff and trapping sediments and nutrients. Non-structural control practices are most applicable in tidal areas where erosion rates are 2 feet per year or less.6 Source: Tony Allred ------- SEPTIC BMPS BMP: Septic Connections/Hookups Description: Septic connections/hookups represent the replacement of traditional septic systems with connection to and treatment at wastewater treatment plants (WWTPs). Source: Vic Giordano ------- BMP: Septic Denitrification Description: Septic denitrification represents the replacement of traditional septic systems with more advanced systems that have additional nitrogen removal capabilities. Traditional septic systems usually consist of a large tank designed to hold the wastewater allowing grits and solids time for settling and decomposition. Wastewater then flows to the second component, the drainfield. An enhanced septic system like that shown can provide further treatment of nitrogen through processes that encourage denitrification of the wastewater.6 Aerobic Unit Treated Wastewater Effluent Tank :¦$ Box Air Compressor—i chamber Source: MDE ------- BMP: Septic Pumping Description: Septic systems achieve nutrient reductions through several types of management practices, including frequent maintenance and pumping. On average, septic tanks need to be pumped once every three to five years to maintain effectiveness. The pumping of septic tanks is one of several measures that can be implemented to protect soil absorption systems from failure. When septic tanks are pumped and sewage removed, the septic system's capacity to remove settable and floatable solids from wastewater is increased.0 ------- FOOTNOTES Center for Watershed Protection and Maryland Department of the Environment. (2000). 2000 Maryland Stormwater Design Manual Volumes I & II. Chesapeake Bay Program Agriculture Nutrient Reduction Workgroup. (11/3/03). "Agricultural BMP Descriptions." Chesapeake Bay Program Tributary Strategy Workgroup. (2003). Best Management Practices - Questions and Answers. Retrieved December 11, 2003, from Chesapeake Bay Program Web Site. http://www.chesapeakebav.net/pubs/wateraualitvcriteria/doc-bmp Q and A.pdf Chesaepake Bay Program Urban Storm Water Workgroup. (2003). "Stream Restoration In Urban Areas: Crediting Jurisdictions for Pollutant Load Reductions." Conservation Plan (n.d.). Retrieved December 12, 2003, from WebRef.Org Web Site. http://www.webref.Org/aariculture/c/conservation plan.htm Technical Reference for Maryland's Tributary Strategies: Documentation for \ Data Sources and Methodologies Used in Developing Nutrient Reduction and Cost Estimates for Maryland's Tributary Strategies (January 2003). Retrieved December 12, 2003, from Maryland Department of Natural Resources Web Site, (http://www.dnr.state.md.us/bav/tribstrat/tsdw/technical reference.pdf) U.S. Department of the Interior, Office of Surface Mining, (n.d.). Retrieved December 22, 2003, from The Office of Surface Mining Web Site, (http://www.osmre.gov/) ------- |