Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters and Irrigation systems
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Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters
EPA 840-B-92-002 January 1993
* Chapter 1: Introduction
* Chapter 2: Management Measures for Agricultural Sources
* Agriculture Chapter Factsheet
* Chapter 3: Management Measures for Forestry
* Forestry Chapter Factsheet
* Chapter 4: Management Measures for Urban Areas
* Urban Chapter Factsheet
* Chapter 5: Management Measures for Marinas and Recreational Boating
* Marinas Chapter Factsheet
* Chapter 6: Management Measures for Hydromodification: Channelization and Channel Modification, Dams, and Steambank and Shoreline Erosion
* Hydromodification Chapter Factsheet
* Chapter 7: Management Measures for Wetlands, Riparian Areas, and Vegetated Treatment Systems
* Wetlands Chapter Factsheet
* Chapter 8: Monitoring and Tracking Techniques to Accompany Management Measures
Chapter 1: Introduction
I. Background
A. Nonpoint Source Pollution
1. What Is Nonpoint Source Pollution?
2. National Efforts to Control Nonpoint Pollution
B. Coastal Zone Management
C. Coastal Zone Act Reauthorization Amendments of 1990
1. Background and Purpose of the Amendments
2. State Coastal Nonpoint Pollution Control Programs
3. Management Measures Guidance
D. Program Implementation Guidance
II. Development of the Management Measures Guidance
A. Process Used to Develop This Guidance
B. Scope and Contents of This Guidance
1. Categories of Nonpoint Sources Addressed
2. Relationship Between This Management Measures Guidance for Coastal Nonpoint Sources and NPDES Permit Requirements for Point Sources
3. Contents of This Guidance
III. Technical Approach Taken in Developing This Guidance
A. The Nonpoint Source Pollution Process
1. Source Control
2. Delivery Reduction
B. Management Measures as Systems
C. Economic Achievability of the Proposed Management Measures
Back to the Guidance Table of Contents
Chapter 2: Management Measures for Agricultural Sources
Introduction
A. What “Management Measures” Are
B. What “Management Practices” Are
C. Scope of This Chapter
D. Relationship of This Chapter to Other Chapters and to Other EPA Documents
E. Coordination of Measures
F. Pollutants That Cause Agricultural Nonpoint Source Pollution
1. Nutrients
2. Sediment
3. Animal Wastes
4. Salts
5. Pesticides
6. Habitat Impacts
II. Management Measures for Agricultural Sources
A. Erosion and Sediment Control Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Effectiveness Information
5. Erosion and Sediment Control Management Practices
6. Cost Information
B1. Management Measure for Facility Wastewater and Runoff from Confined Animal Facility Management (LargeUnits)
1. Applicability
2. Description
3. Management Measure Selection
4. Effectiveness Information
5. Confined Animal Facility Management Practices
6. Cost Information
B2. Management Measure for Facility Wastewater and Runoff from Confined Animal Facility Management (Small Units)
1. Applicability
2. Description
3. Management Measure Selection
4. Effectiveness Information
5. Confined Animal Facility Management Practices
6. Cost Information
C. Nutrient Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Effectiveness Information
5. Nutrient Management Practices
6. Cost Information
D. Pesticide Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Effectiveness Information
5. Pesticide Management Practices
6. Cost Information
7. Relationship of Pesticide Management Measure to Other Programs
E. Grazing Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Effectiveness Information
5. Range and Pasture Management Practices
6. Cost Information
F. Irrigation Water Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Effectiveness Information
5. Irrigation Water Management Practices
6. Cost Information
III. Glossary
IV. References
Agriculture Chapter Factsheet
What Is the Coastal Nonpoint Pollution Program?
Section 6217 of the Coastal Zone Act Reauthorization Amendments of 1990 (CZARA) requires coastal states (including Great Lakes states) with approved coastal zone management programs to address nonpoint pollution impacting or threatening coastal waters. States must submit Coastal Nonpoint Pollution Control Programs for approval to both the U.S. Environmental Protection Agency (EPA) and the National Oceanic and Atmospheric Administration (NOAA). Requirements for state programs are described in a document entitled “Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance” and are summarized in a separate fact sheet.
What Are Management Measures?
CZARA requires EPA, in consultation with NOAA and other federal agencies, to publish guidance specifying management measures to restore and protect coastal waters from specific categories of nonpoint source pollution. EPA has done so in a document entitled “Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters”. State Coastal Nonpoint Programs must provide for implementation of these measures or alternative management measures in conformity with these measures in the coastal management area generally. “Management measures” are defined by law to be economically achievable measures that reflect the best available technology for reducing pollutants. States may select from a wide range of practices or combinations of practices that will achieve the level of control specified in the management measure. This fact sheet summarizes the management measures applicable to agricultural sources. Other fact sheets summarize the measures for forestry, urban areas, marinas and recreational boating, hydro- modification, and wetlands/riparian areas.
What Are the Sources of Agriculture-Related Nonpoint Source Pollution?
The primary agricultural nonpoint source pollutants are nutrients (particularly nitrogen and phosphorus), sediment, animal wastes, pesticides, and salts. Agricultural nonpoint sources enter srface water through direct surface runoff or through seepage to ground water that discharges to a surface water outlet. Various farming activities result in the erosion of soil particles. The sediment produced by erosion can damage fish habitat and wetlands and, in addition, often transports excess agricultural chemicals resulting in contaminated runoff. This runnoff in turn affects changes to aquatic habitat such as temperature increases and decreased oxygen. The most common sources of excess nutrients in surface water from nonpoint sources are chemical fertilizers and manure from animal facilities. Such nutrients cause eutrophication in surface water. Pesticides used for pest control in agricultural operations can also contaminate surface as well as ground-water resources. Return flows, runoff, and leachate from irrigated lands may transport sediment, nutrients, salts, and other materials. Finally, improper grazing practices in riparian, as well as upland areas, can also cause water quality degradation.
MANAGEMENT MEASURES SUMMARY
SEDIMENT/EROSION CONTROL — Soil erosion is one of the leading causes of water pollution in the United States. The goal of this measure is to minimize the delivery of sediment from agricultural lands to receiving waters. Land owners have a choice of one of two approaches: (1) apply the erosion component of the U.S. Department of Agricultures Conservation Management System through such practices as conservation tillage, strip cropping, contour farming, and terracing OR (2) design and install a combination of practices to remove settleable solids and associated pollutants in runoff for all but the larger storms.
CONFINED ANIMAL FACILITY — Animal waste contaminates many of our waters with pathogens and nutrients. The management measure for ALL new facilities and existing facilities over a certain size is to limit discharges from confined animal facilities to waters of the United States by storing wastewater and runoff caused by all storms up to and including the 25-year, 24-hour frequency storm. For smaller existing facilities, the management measure is to design and implement systems that collect solids, reduce contaminant concentrations, and reduce runoff to minimize the discharge of contaminants in both facility wastewater and runoff caused by all storms up to and including 25-year, 24-hour frequency storms. This measure also specifies management of stored runoff and solids through proper waste utilization and use of disposal methods which minimize impacts to surface/ground water. Confined animal facilities required to obtain a discharge permit under the NPDES permit program are not subject to these management measures.
NUTRIENT MANAGEMENT — This measure calls for development and implementation of comprehensive nutrient management plans. The fundamentals of a comprehensive nutrient management plan include a nutrient budget for the crop, identification of the types and amounts of nutrients necessary to produce a crop based on realistic crop yield expectations, and an identification of the environmental hazards of the site. Other items called for in the measure include soil tests and other tests to determine crop nutrient needs and proper calibration of nutrient equipment.
PESTICIDE MANAGEMENT — This measure is designed to minimize water quality problems by reducing pesticide use,improving the timing and efficiency of application, preventing backflow of pesticides into water supplies, and improving calibration of pesticide spray equipment. A key component of this measure is use of integrated pest management (IPM) strategies. IPM strategies include evaluating current pest problems in relation to the cropping history, previous pest control measures, and applying pesticides only when an economic benefit to the producer will be achieved, i.e., application based on economic thresholds. If pesticide applications are necessary, pesticides should be selected based on consideration of their environmental impacts such as persistence, toxicity, and leaching potential.
LIVESTOCK GRAZING — The goal of this measure is to protect sensitive areas. Sensitive areas include streambanks, wetlands, estuaries, ponds, lake shores, and riparian zones. Protection is to be achieved with improved grazing management that reduces the physical distance and direct loading of animal waste and sediment caused by livestock by restricting livestock access to sensitive areas through a range of options. In addition, upland erosion is to be reduced by either: (1) applying the range and pasture components of a Conservation Management System or (2) maintaining the land in accordance with the activity plans established by either the Bureau of Land Management or the Forest Service. Such techniques include the restriction of livestock from sensitive areas through locating salt, shade, and alternative drinking sources away from sensitive areas, and providing livestock stream crossings.
IRRIGATION — This measure promotes an effective irrigation system that delivers necessary quantities of water yet reduces nonpoint pollution to surface waters and groundwater. To achieve this, the measure calls for uniform application of water based upon an accurate measurement of cropwater needs and the volume of irrigation water applied. When applying chemicals through irrigation (a process known as chemigation), special additional precautions apply. The measure also recognizes that states water laws that conflict with the measure will take precedence over the measure.
Back to the Guidance Table of Contents
Chapter 3: Management Measures for Forestry
I. Introduction
A. What “Management Measures” Are
B. What “Management Practices” Are
C. Scope of This Chapter
D. Relationship of This Chapter to Other Chapters and to Other EPA Documents
E. Background
1. Pollutant Types and Impacts
2. Forestry Activities Affecting Water Quality
F. Other Federal, State, and Local Silviculture Programs
1. Federal Programs
2. State Forestry NPS Programs
3. Local Governments
II. Forestry Management Measures
A. Preharvest Planning
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
B. Streamside Management Areas (SMAs)
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
C. Road Construction/Reconstruction
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
D. Road Management
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
E. Timber Harvesting
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
F. Site Preparation and Forest Regeneration
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
G. Fire Management
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
H. Revegetation of Disturbed Areas
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
I. Forest Chemical Management
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Relationship of Management Measure Components for Pesticides to Other Programs
J. Wetlands Forest Management
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
Glossary
References
Back to the Guidance Table of Contents
Forestry Chapter Factsheet
What Is the Coastal Nonpoint Pollution Program?
Section 6217 of the Coastal Zone Act Reauthorization Amendments of 1990 (CZARA) requires coastal states (including Great Lakes states) with approved coastal zone management programs to address nonpoint pollution impacting or threatening coastal waters. States must submit Coastal Nonpoint Pollution Control Programs for approval to both the U.S. Environmental Protection Agency (EPA) and the National Oceanic and Atmospheric Administration (NOAA). Requirements for state programs are described in a document entitled “Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance” and are summarized in a separate fact sheet.
What Are Management Measures?
CZARA requires EPA, in consultation with NOAA and other federal agencies, to publish guidance specifying “management measures” to restore and protect coastal waters from specific categories of nonpoint source pollution. EPA has done so in a document entitled “Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters.” State Coastal Nonpoint Pollution Control Programs must provide for implementation of these measures or alternative management measures in conformity with these measures, in the coastal management area generally. “Management measures” are defined by law to be economically achievable measures that reflect the best available technology for reducing pollutants. States may select from a wide range of practices or combinations of practices that will achieve the level of control specified in the management measure. This fact sheet summarizes the management measures applicable to forestry sources. Other fact sheets summarize the measures for agriculture, urban areas, marinas and recreational boating, hydromodification, and wetlands/riparian areas.
What Are the Major Sources of Pollutants from Forestry Operations?
Silvicultural nonpoint source pollution impacts depend on site characteristics, climatic conditions, and the forest practice employed. Sediment, nutrients, pesticides, and temperature are pollutants commonly associated with forestry activities.
MANAGEMENT MEASURES SUMMARY
PREHARVEST PLANNING — The objective of this management measure is to ensure that silvicultural activities, including timber harvesting, site preparation, and associated road construction, are conducted in a way that takes into account potential nonpoint source pollutant delivery to surface waters. Preharvest planning has been demonstrated to play an important role in the control of nonpoint source pollution and efficient forest management operations. Components of this measure address key aspects of forestry operations relevant to water quality protection, including the timing, location, and design of harvesting and road construction, the identification of sensitive areas or high-erosion-hazard areas; and the potential for additional cumulative contributions to existing water quality impairments.
STREAMSIDE MANAGEMENT AREAS (SMA) — This management measure establishes areas along surface waters that are managed to protect the water quality of the adjacent waterbody. Streamside Management Areas (SMAs) protect against soil disturbance and reduce the delivery to waterbodies of sediment and nutrients from upslope activities. Canopy species in SMAs shade waterbodies, which moderates water temperature, and provide the detritus that often serves as an energy source for stream ecosystems. Trees in the SMA also provide a source of large, woody debris to waterbodies.
ROAD CONSTRUCTION/RECONSTRUCTION — Road construction is often the largest source of silviculture-produced sediment. The purpose of this management measure is to reduce the generation and delivery of sediment from road construction or reconstruction. This is to be accmplished by following the preharvest plan layouts and designs for the road system, incorporating adequate drainage structures, and properly installing stream crossings. Other components of this measure include avoiding constructing roads in SMAs, removing debris from streams, and stabilizing areas of disturbed soil such as road fills.
ROAD MANAGEMENT — The objective of this management measure is to manage existing roads to prevent sedimentation and pollution from runoff-transported materials. This management measure describes how to manage existing roads to minimize erosion, maintain stability, and reduce the risk of failure or decreased effectiveness of drainage structures and stream crossings. Components of this measure include the use of inspections and maintenance actions to prevent erosion of road surfaces and ensure the continued effectiveness of stream crossing structures. The measure also addresses appropriate actions for closing roads that are no longer in use.
TIMBER HARVESTING — This management measure is intended to reduce NPS pollution resulting from timber harvesting operations. The measure includes components for the location of landings, for the operation of groundskidding and cable yarding equipment, and for the prevention of pollution from petroleum products. Harvesting practices that protect water quality and soil productivity can also reduce total mileage of roads and skid trails, lower equipment maintenance costs, and provide better road protection and reduce road maintenance. Appropriate skid trail location and drainage and proper harvesting in SMAs are addressed by this measure. Erosion from the siting and operation of timber harvest operations can be reduced by conducting preharvest planning.
SITE PREPARATION AND FOREST REGENERATION — In some areas mechanical site preparation is of great concern for potential impacts to water quality. This is especially true in areas that have steep slopes on highly erodible soils, or where the site is located in close proximity to a waterbody. Careful regeneration of harvested forest lands is important in providing water quality protection from disturbed soils. This management measure is intended to reduce the impacts of mechanical site preparation and regeneration operations and to confine on-site potential nonpoint source pollution. Components of this measure address keeping slash materials out of drainages, operating machinery on the contour and protecting the ground cover in ephemeral drainages and SMAs.
FIRE MANAGEMENT — Prescribed burning is aimed at reducing slash and competition for nutrients among seedlings and protecting against wildfire. Prescribed fires that burn intensely on steep slopes in close proximity to streams and that remove most of the forest floor and litter down to the mineral soil, are most likely to adversely affect water quality. The purpose of this management measure is to reduce the potential nonpoint source pollution and erosion resulting from prescribed fire for site preparation and from methods for suppression of wildfire. Prescribed fires should be conducted under conditions to avoid the loss of litter and incorporated soil organic matter. Bladed firelines should be stabilized to prevent erosion, or practices such as handlines, firebreaks, or hose lays should be used where possible.
REVEGETATION OF DISTURBED AREAS — Revegetation of areas of disturbed soil can successfully prevent sediment and pollutants associated with the sediment (such as nutrients) from entering nearby streams. The objective of this management measure is to reduce erosion and sedimentation by the rapid revegetation of areas of soil disturbance from harvesting and road construction. The disturbed areas to be revegetated are those localized areas within harvest units or road systems where mineral soil is exposed or agitated such as road cuts, fill slopes, landing surfaces, cable corridors, or skid trails.
FOREST CHEMICAL MANAGEMENT — Chemicals used in forest management are generally pesticides (insecticides, herbicides, and fungicides) and fertilizers. Since pesticides may be toxic, they must be properly mixed, transported, loaded, and applied and their containers must be properly disposed of to prevent potential nonpoint source pollution. Fertilizers must also be properly handled and applied since they also may be toxic or may shift surface water energy dynamics, depending on the exposure and concentration. The objective of this management measure is to ensure that the application of pesticides and fertilizers does not lead to contamination of surface waters. Components of this measure include applications by skilled workers according to label instructions, careful prescription of the type and amount of chemical to be applied, and the use of buffer areas for surface waters to prevent direct application or deposition.
WETLAND FOREST MANAGEMENT — Forested wetlands provide many beneficial water quality functions and provide habitat for aquatic life. The purpose of this management measure is to protect the aquatic functions of forested wetlands.
Chapter 4: Management Measures for Urban Areas
I. Introduction
A. What “Management Measures” Are
B. What “Management Practices” Are
C. Scope of This Chapter
D. Relationship of This Chapter to Other Chapters and to Other EPA Documents
E. Overlap Between This Management Measure Guidance for Control of Coastal Nonpoint Sources and Storm Water Permit Requirements for Point Sources
1. The Storm Water Permit Program
2. Coastal Nonpoint Pollution Control Programs
3. Scope and Coverage of This Guidance
F. Background
1. Urbanization and Its Impacts
2. Nonpoint Source Pollutants and Their Impacts
3. Opportunities
II. Urban Runoff
A. New Development Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Effectiveness and Cost Information
B. Watershed Protection Management Measure
1. Applicability
2. Description
3. Management Measure Selection and Effectiveness Information
4. Watershed Protection Practices and Cost Information
5. Land or Development Rights Aquisition Practices and Cost Information
C. Site Development Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices and Cost Information for Control of Erosion During Site Development
5. Site Planning Practices
III. Construction Activites
A. Construction Site Erosion and Sediment Control Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Erosion Control Practices
5. Sediment Control Practices
6. Effectiveness and Cost Information
B. Construction Site Chemical Control Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
IV. Existing Development
A. Existing Development Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Effectiveness and Cost Information
V. Onsite Disposal Systems
A. New Onsite Disposal System Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Effectiveness and Cost Information
B. Operating Onsite Disposal Systems Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
VI. Pollution Prevention
A. Pollution Prevention Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices, Effectiveness Information, and Cost Information
VII. Roads, Highways, and Bridges
A. Management Measure for Planning, Siting, and Developing Roads and Highways
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Effectiveness and Cost Information
B. Management Measure for Bridges
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Effectiveness and Cost Information
C. Management Measure for Construction Projects
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Effectiveness and Cost Information
D. Management Measure for Construction Site Chemical Control
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Effectiveness and Cost Information
E. Management Measure for Operation and Maintainance
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Effectiveness and Cost Information
F. Management Measure for Road, Highway, and Bridge Runoff Systems
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Effectiveness and Cost Information
6. Pollutants of Concern
VIII. Glossary
IX. References
Urban Areas Chapter Factsheet
What Is the Coastal Nonpoint Pollution Program?
Section 6217 of the Coastal Zone Act Reauthorization Amendments of 1990 (CZARA) requires coastal states (including Great Lakes states) with approved coastal zone management programs to address nonpoint pollution impacting or threatening coastal waters. States must submit Coastal Nonpoint Pollution Control Programs for approval to both the U.S. Environmental Protection Agency (EPA) and the National Oceanic and Atmospheric Administration (NOAA). Requirements for state programs are described in a document entitled “Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance” and are summarized in a separate fact sheet.
What Are Management Measures?
CZARA requires EPA, in consultation with NOAA and other federal agencies, to publish guidance specifying “management measures” to restore and protect coastal waters from specific categories of nonpoint source pollution. EPA has done so in a document entitled “Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters.” State Coastal Nonpoint Pollution Control Programs must provide for implementation of these measures or alternative managment measures in conformity with these measures in the coastal managemen area generally. “Management measures” are defined by law to be economically achievable measures that reflect the best available technology for reducing pollutants. States may select from a wide range of practices or combinations of practices that will achieve the level of control specified in the management measure. This fact sheet summarizes the management measures applicable to urban areas. Other fact sheets summarize the measures for agriculture, forestry, marinas and recreational boating, hydromodification, and wetlands/riparian areas.
What Are the Major Sources of Urban Nonpoint Source Pollution?
Urbanization has been linked to the degradation of urban waterways. The major pollutants found in runoff from urban areas include sediment, nutrients, oxygen-demanding substances, road salts, heavy metals, petroleum hydrocarbons, pathogenic bacteria, and viruses. Suspended sediments constitute the largest mass of pollutant loadings to receiving waters from urban areas. Construction is a major source of sediment erosion. Nutrient and bacterial sources of contamination include fertilizer usage, pet wastes, leaves, grass clippings, and faulty septic tanks. Petroleum hydrocarbons result mostly from automobile sources.
MANAGEMENT MEASURES SUMMARY
NEW DEVELOPMENT — The new development management measure is intended to mitigate the effects of new development on water quality. This measure specifies that runoff from new development be managed so as to meet two conditions:
(1) The average annual total suspended solid (TSS) loadings after construction is completed are reduced:
a) by 80 percent, or
b) so that they are no greater than predevelopment loadings; and
(2) To the extent practicable, post-development peak runoff rate and average volume are maintained at levels that are similar to predevelopment levels. New developments required to obtain NPDES permits are not subject to this management measure.
WATERSHED PROTECTION/SITE DEVELOPMENT — The purpose of these measures is to encourage comprehensive planning for development on a watershed scale and for small-scle site development as well, including planning and designing to protect sensitive ecological areas, minimize land disturbances and retain natural drainage and vegetation whenever possible.
CONSTRUCTION EROSION/SEDIMENT CONTROL — The purpose of this measure is to reduce erosion and transport of sediment from construction sites to surface water. A sediment and erosion control plan should be developed and approved prior to land disturbance. This measure applies to construction sites of less than 5 acres.
CONSTRUCTION SITE CHEMICAL CONTROL — This measure addresses the transport of toxic chemicals to surface water by limiting the application, generation, and migration of chemical contaminants (i.e., petrochemicals, pesticides, nutrients) and providing proper storage and disposal.
EXISTING DEVELOPMENT — This measure addresses reduction of pollution loadings from already developed areas. Watershed management programs should be developed that identify the sources, specify appropriate controls such as retrofitting or the establishment of buffer strips, and provide a schedule by which these controls are to be implemented.
NEW ONSITE DISPOSAL SYSTEMS — This measure addresses nutrient/pathogen loadings to surface water from new on-site disposal systems. The measure specifies that new onsite disposal systems (OSDS) are to be designed, installed and operated properly and to be situated away from open waterbodies and sensitive resources such as wetlands, and floodplains. Protective separation between the OSDS and the groundwater table is to be established. The OSDS unit should be designed to reduce nitrogen loadings in areas where surface waters may be adversely affected.
OPERATING ONSITE DISPOSAL SYSTEMS — This management measure calls for policies and systems to operate and maintain OSDS so as to prevent surface water discharge and reduce pollutant loadings to ground water. It also calls for inspection at regular time intervals and repair or replacement of faulty systems.
POLLUTION PREVENTION — This measure includes techniques and activities to prevent nonpoint source pollutants from entering surface waters. Primary emphasis is placed on public education to promote methods for proper disposal and/or recycling of hazardous chemicals, pet waste management strategies, management practices for lawns and gardens, OSDSs, and commercial enterprises such as service stations and parking lots.
SITING ROADS, HIGHWAYS, AND BRIDGES — The measure calls for roads, highways, and bridges to be situated away from areas that are sensitive ecosystems and susceptible to erosion and sediment loss. The siting of such structures should not adversely impact water quality, minimize land disturbances, and retain natural vegetation and drainage features.
CONSTRUCTION PROJECTS FOR ROADS, HIGHWAYS, AND BRIDGES — This measure calls for the development and implementation of an approved erosion and sediment control plan prior to construction, which would reduce erosion and improve retention of sediments onsite during and after construction.
CONSTRUCTION SITE CHEMICAL CONTROL FOR ROADS, HIGHWAYS, AND BRIDGES — The measure limits toxic and nutrient loadings at construction sites by ensuring the proper use, storage, and disposal of toxic materials to prevent significant chemical and nutrient runoff to surface water.
OPERATION AND MAINTENANCE FOR ROADS, HIGHWAYS, AND BRIDGES — This measure provides an operation and maintenance approach designed to reduce pollutant loadings to receiving waters during operation and maintenance of roads, highways, and bridges.
RUNOFF SYSTEMS FOR ROADS, HIGHWAYS, AND BRIDGES — This measure specifies development of runoff management systems to reduce pollutant concentrations in runoff from existing roads, highways, and bridges. Runoff management systems should identify priority pollutant reduction opportunities and schedule implementation of retrofit projects to protect impacted areas and threatened surface waters.
Back to the Guidance Table of Contents
Chapter 5: Management Measure for Marinas and Recreational Boating
I. Introduction
A. What “Management Measures” Are
B. What “Management Practices” Are
C. Scope of This Chapter
D. Relationship of This Chapter to Other Chapters and to Other EPA Documents
E. Problem Statement
F. Pollutant Types and Impacts
1. Toxicity in the Water Column
2. Increased Pollutant Levels in Aquatic Organisms
3. Increased Pollutant Levels in Sediments
4. Increased Levels of Pathogen Indicators
5. Disruption of Sediment and Habitat
6. Shoaling and Shoreline Erosion
G. Other Federal State Marina and Boating Programs
1. NPDES Storm Water Program
2. Other Regulatory Programs
H. Applicability of Management Measure
II. Siting and Design
A. Marina Flushing Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
B. Water Quality Assessment Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
C. Habitat Assessment Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
D. Shoreline Stabilization Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
E. Storm Water Runoff Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
F. Fueling Station Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
G. Sewage Facility Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
III. Marina and Boat Operation Management Measure
A. Solid Waste Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
B. Fish Waste Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
C. Liquid Material Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
D. Petroleum Control Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
E. Boat Cleaning Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
F. Public Education Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
G. Maintainance of Sewage Facilities Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
H. Boat Operation Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
IV. Glossary
V. References
Back to the Guidance Table of Contents
Marinas Chapter Factsheet
What Is the Coastal Nonpoint Pollution Program?
Section 6217 of the Coastal Zone Act Reauthorization Amendments of
1990 (CZARA) requires coastal states (including Great Lakes states)
with approved coastal zone management programs to address nonpoint
pollution impacting or threatening coastal waters. States must
submit Coastal Nonpoint Pollution Control Programs for approval to
both the U.S. Environmental Protection Agency (EPA) and the National
Oceanic and Atmospheric Administration (NOAA). Requirements for
state programs are described in a document entitled “Coastal
Nonpoint Pollution Control Program: Program Development and Approval
Guidance” and are summarized in a separate fact sheet.
What Are Management Measures?
CZARA requires EPA, in consultation with NOAA and other federal
agencies, to publish guidance specifying “management measures” to
restore and protect coastal waters from specific categories of
nonpoint source pollution. EPA has done so in a document entitled
“Guidance Specifying Management Measures for Sources of Nonpoint
Pollution in Coastal Waters.” State Coastal Nonpoint Pollution
Control Programs must provide for implementation of these measures
or alternative management measures in conformity with these measures
in the coastal management area generally. “Management measures” are
defined by law to be economically achievable measures that reflect
the best available technology for reducing pollutants. States may
select from a wide range of practices or combinations of practices
that will achieve the level of control specified in the management
measure. This fact sheet summarizes the management measures
applicable to marinas and recreationa boating. Other fact sheets
summarize the measures for agriculture, forestry, urban areas,
hydromodification, and wetlands/riparian areas.
What Are the Nonpoint Source Pollution Problems Associated with
Marinas and Recreational Boating?
Marinas are located right at the waters edge, and often there is no
buffering of pollutants coming from boats or transported by runoff
from parking lots and hull maintenance areas. Documented adverse
environmental impacts include dissolved oxygen deficiencies and high
concentrations of toxic metals in aquatic organisms. In addition,
construction activities can lead to the physical destruction of
sensitive ecosystems and bottom-dwelling aquatic communities.
MANAGEMENT MEASURES SUMMARY
MARINA FLUSHING — The measure requires that marina siting and
design allow for maximum flushing of the water supply for the site.
Adequate flushing reduces the potential for the stagnation of water
in a marina and helps to maintain the biological productivity and
reduce the potential for toxic accumulation in bottom sediment.
WATER QUALITY ASSESSMENT — This measure specifies that water
quality be considered in the siting and design of both new and
expanding marinas.
HABITAT ASSESSMENT — Marinas should be designed and located so as
to protect against adverse impacts on shellfish resources, wetlands,
submerged aquatic vegetation, and other important habitat areas as
designated by local, state, or federal governments.
SHORELINE STABILIZATION — Where shoreline erosion is a nonpoint
source pollution problem, shorelines should be stabilized.
Vegetative methods are strongly preferred unless structural methods
are cost-effective.
STORMWATER RUNOFF — This measure, which applies to runoff from the
marina site only, specifies implementation of runoff control
strategies which include the use of pollution prevention activities
and the proper design of hull maintenance areas. At least 80% of
suspended solids must be removed from stormwater runoff coming from
the hull maintenance areas. Marinas which obtain a NPDES permit for
their hull maintenance areas are not required to conform to this
hull maintenance area provision.
FUELING STATION DESIGN — This measure specifies that fueling
stations should be located and designed so that, in the case of an
accident, spill contaminants can be contained in a limited area.
Fueling stations should have fuel containment equipment as well as
a spill contingency plan
SEWAGE FACILITIES — To prevent the discharge of sewage directly to
coastal waters, new and expanding marinas are to install pumpout,
pump station, and restroom facilities where needed.
SOLID WASTE — This measure specifies that solid wastes produced by
the operation, cleaning, maintenance, and repair of boats should be
properly disposed of to limit their entry to surface waters.
FISH WASTES — In sufficient quantity, fish wastes can result in the
depletion of dissolved oxygen and odor problems. To address this
concern, the measure requires that sound fish waste management be
promoted through a combination of fish cleaning restrictions, public
education, and proper disposal.
LIQUID MATERIAL — This management measure provides for appropriate
storage, transfer, containment, and disposal facilities for liquid
materials commonly used in boat maintanance and encourages the
recycling of these materials.
PETROLEUM CONTROL — This measure addresses the problem of fuel and
oil leaks, which often occur during the refueling and operation of
boats. The amount of fuel and oil leakage from fuel tank air vents
should be reduced.
BOAT CLEANING — This measure minimizes the use of potentially
harmful hull cleaners and bottom paints and their release to marinas
and coastal waters.
PUBLIC EDUCATION — Public education/outreach/training programs
should be instituted for boaters, as well as marina operators, to
prevent improper disposal of polluting materials.
MAINTENANCE OF SEWAGE FACILITIES — This measure specifies that
pumpout facilities be maintained in operational condition and that
their use be encouraged to reduce untreated sewage discharges to
surface waters.
BOAT OPERATION — This measure deals with ecological problems
resulting from boating operations outside marinas. In shallow areas,
intense boating activities may contribute to shoreline erosion. The
measure is designed to prevent increased turbidity and physical
destruction of shallow-water habitat resulting from boating
activitis.
Chapter 6: Management Measures for Hydromodification:
Channelization and Channel Modification, Dams, and Steambank and Shoreline Erosion
I. Introduction
A. What “Management Measures” Are
B. What “Management Practices” Are
C. Scope of This Chapter
D. Relationship of This Chapter to Other Chapters and to Other EPA Documents
II. Channelization and Channel Modification Management
A. Management Measure for Physical and Chemical Characteristics of Surface Waters
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Costs for Modeling Practices
B. Instream and Riparian Habitat Management Measure
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
III. Dams Management Measures
A. Management Measure for Erosion and Sediment Control
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Effectiveness for All Practices
6. Costs for Modeling Practices
B. Management Measure for Chemical and Pollutant Control
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
C. Management Measure for Protection of Surface Water Quality and Instream and Riparian Habitat
1. Applicability
2. Description
3. Management Measure Selection
4. Introduction to Practices
5. Practices for Aeration of Reservoir Waters and Releases
6. Practices to Improve Oxygen Levels in Tailwaters
7. Practices for Adjustments in the Operational Procedures of Dams for Improvements of Water Quality
8. Watershed Protection Practices
9. Practices to Restore or Maintain Aquatic and Riparian Habitat
10. Practices to Maintain Fish Passage
11. Costs for All Practices
IV. Streambank and Shoreline Erosion Management Measure
A. Management Measure for Eroding Streambanks and Shorelines
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Costs for All Practices
V. Glossary
VI. References
A. Channelization and Channel Modification
B. Dams
C. Streambank and Shoreline Erosion
Back to the Guidance Table of Contents
Hydromodification Chapter Factsheet
What Is the Coastal Nonpoint Pollution Program?
Section 6217 of the Coastal Zone Act Reauthorization Amendments of
1990 (CZARA) requires coastal states (including Great Lakes states)
with approved coastal zone management programs to address nonpoint
pollution impacting or threatening coastal waters. States must
submit Coastal Nonpoint Pollution Control Programs for approval to
both the U.S. Environmental Protection Agency (EPA) and the National
Oceanic and Atmospheric Administration (NOAA). Requirements for
state programs are described in a document entitled “Coastal
Nonpoint Pollution Control Program: Program Development and Approval
Guidance” and are summarized in a separate fact sheet.
What are Management Measures?
CZARA requires EPA, in consultation with NOAA and other federal
agencies, to publish guidance specifying “management measures” to
restore and protect coastal waters from specific categories of
nonpoint source pollution. EPA has done so in a document entitled
“Guidance Specifying Management Measures for Sources of Nonpoint
Pollution in Coastal Waters.” State Coastal Nonpoint Pollution
Control Programs must provide for implementation of these measures
or alternative management measures in conformity with these measures
in the coastal management area generally. “Management Measures” are
defined by law to be economically achievable measures that reflect
the best available technology for reducing pollutants. States may
select from a wide range of practices or combinations of practices
that will achieve the level of conrol specified in the management
measure. This fact sheet summarizes the management measures
applicable to hydromodification. Other fact sheets summarize the
measures for agriculture, forestry, urban areas, marinas and
recreational boating, and wetlands/riparian areas.
What Are the Nonpoint Source-Related Problems Associated with
Hydromodification?
Hydromodification activities have been separated into the categories
of channelization and channel modification, dams, and streambank and
shoreline erosion.
A frequent result of channelization and channel modification
activities is a diminished suitability of instream and streamside
habitat for fish and wildlife. They can also alter instream patterns
of water temperature and sediment type, as well as the rates and
paths of sediment erosion, transport, and deposition. Hardening of
banks along waterways has increased the movement of NPS pollutants
from the upper reaches of watersheds into coastal waters.
Dams can adversely impact the hydraulic regime, the quality of the
surface waters, and habitat in the stream or river where they are
located. A variety of impacts can result from the siting,
construction, and operation of these facilities.
The erosion of shorelines and streambanks is a natural process that
can have either beneficial or adverse impacts on the creation and
maintenance of riparian habitat. Excessively high sediment loads can
smother submerged aquatic vegetation, cover shellfish beds and tidal
flats, fill in riffle pools, and contribute to increased levels of
turbidity and nutrients.
MANAGEMENT MEASURES SUMMARY
Management Measures for Channelization and Channel Modification
PHYSICAL AND CHEMICAL CHARACTERISTICS OF SURFACE WATERS — This
measure ensures that the planning process for new channelization
projects includes an evaluation of the potential effects on the
physical and chemical characteristics of surface waters that may
occur as a result of the proposed work. The measure encourages
planning and design of new projects to reduce undesirable impacts.
The operation and maintenance programs for existing modified
channels should identify and implement any available opportunities
to improve the physical and chemical characteristics of surface
waters in those channels.
INSTREAM AND RIPARIAN HABITAT RESTORATION FOR CHANNELIZATION AND
CHANNEL MODIFICATION — This measure ensures that the planning
process for new channelization projects includes an evaluation of
the potential effects on instream and riparian habitat that may
occur as a result of the proposed work. The measure encourages
planning and design of new projects to reduce undesirable impacts.
The operation and maintenance programs for existing modified
channels should identify opportunities to restore instream and
riparian habitat in those channels. The habitat characteristics
that may be influenced by channelization and channel modification
include: elimination of stream bank vegetation, reduced freshwaer
availability, and accelerated delivery of pollutants.
Management Measures for Dams
These management measures apply to dams 25 feet or more in height
and greater than 15 acre-feet in capacity, or to dams six feet or
more in height and greater that 50 acre-feet in capacity. The
measures also apply only to those projects and activities that fall
outside of existing jurisdiction of the National Pollutant Discharge
Elimination System permit program.
EROSION AND SEDIMENT CONTROL — This measure provides for reducing
erosion and retaining sediment onsite, to the extent practicable,
during and after construction of dams. An approved erosion and
sediment control plan, or similar administrative document that
contains erosion and sediment control provisions, should be prepared
and implemented prior to land disturbance.
CHEMICAL AND POLLUTANT CONTROL — This measure ensures the proper
storage and disposal of certain chemicals, substances, and other
materials that are used in construction or maintenance activities at
dams. These include construction chemicals such as concrete
additives, petrochemicals, solid wastes, cement washout, pesticides
and fertilizers. The measure limits the application, generation,
and migration of toxic substances, and ensures their proper storage
and disposal. The measure also ensures that nutrients are applied
at rates necessary to establish and maintain vegetation without
causing significant nutrient runoff to surface waters.
PROTECTION OF SURFACE WATER QUALITY AND INSTREAM AND RIPARIAN
HABITAT — This measure ensures that the operation of dams will be
assessed for impacts to surface water quality and instream and
riparian habitat, and that the potential for improvement will be
evaluated. Significant nonpoint source pollution problems that
exist from excessive surface water withdrawals will also be assessed
and evaluated.
Management Measure for Streambank and Shoreline Erosion
STREAMBANK AND SHORELINE EROSION — Eroding streambanks and
shorelines should be stabilized, where streambank and shoreline
erosion is a nonpoint source problem. Vegetative methods such as
marsh creation and vegetative bank stabilization (“bioengineering”)
are the preferred methods. The measure also ensures that streambank
and shoreline features such as wetlands and riparian areas with the
potential to reduce NPS pollution are protected. Streambanks and
shorelines should also be protected from erosion due to uses of
either the shorelands or adjacent surface waters.
Chapter 7: Management Measures for Wetlands, Riparian Areas, and Vegetated Treatment Systems
I. Introduction
A. What “Management Measures” Are
B. What “Management Practices” Are
C. Scope of This Chapter
D. Relationship of This Chapter to Other Chapters and to Other EPA Documents
E. Definitions and Background Information
1. Wetlands and Riparian Areas
2. Vegetated Buffers
3. Vegetated Treatment Systems
II. Management Measures
A. Management Measure for Protection of Wetlands and Riparian Areas
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Costs for All Practices
B. Management Measure for Restoration of Wetlands and Riparian Areas
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Costs for All Practices
C. Management Measure for Vegetated Treatment Systems
1. Applicability
2. Description
3. Management Measure Selection
4. Practices
5. Costs for All Practices
III. Glossary
IV. References
Wetlands Chapter Factsheet
What Is the Coastal Nonpoint Pollution Program?
Section 6217 of the Coastal Zone Act Reauthorization Amendments of
1990 (CZARA) requires coastal states (including Great Lakes states)
with approved coastal zone management programs to address nonpoint
pollution impacting or threatening coastal waters. States must
submit Coastal Nonpoint Pollution Control Programs for approval to
both the U.S. Environmental Protection Agency (EPA) and the
National Oceanic and Atmospheric Administration (NOAA).
Requirements for state programs are described in a document entitled
“Coastal Nonpoint Pollution Control Program: Program Development and
Approval Guidance” and are summarized in a separate fact sheet.
What Are Management Measures?
CZARA requires EPA, in consultation with NOAA and other federal
agencies, to publish guidance specifying “management measures” to
restore and protect coastal waters from specific categories of
nonpoint source pollution. EPA has done so in a document entitled
“Guidance Specifying Management Measures for Sources of Nonpoint
Pollution in Coastal Waters.” State Coastal Nonpoint Pollution
Control Programs must provide for implementation of these measures
or alternative management measures in conformity with these measures
in the coastal management area generally. “Management measures” are
defined by law to be economically achievable measures that reflect
the best available technology for reducing pollutants. States may
select from a wide range of practices or combinations ofpractices
that will achieve the level of control specified in the management
measure. Chapters 2-6 of the Guidance specify management measures
that represent the most effective systems of practices to prevent or
reduce coastal nonpoint source pollution from five specific
categories of sources (agriculture, forestry, urban areas, marinas
and recreational boating, and hydromodification). In chapter 7,
management measures are specified that apply to a wide variety of
sources, including the five categories of sources addressed in the
preceding chapters, as well as to the protection and restoration of
wetlands and riparian areas. This fact sheet summarizes the
management measures specified in chapter 7.
What Are Some Activities That Lead to the Destruction of Wetlands
and Riparian Areas ?
Changes to hydrology, geochemistry, substrate, or species
composition may impair the ability of a wetland or riparian area to
function properly. Such alterations can affect the ability of the
wetland or riparian area to act as a filter for excess sedimentation
and nutrients, which can result in deteriorated surface water
quality. The following are examples of typical activities that
often cause such impairment: the drainage of wetlands for additional
cropland, overgrazing, construction of highways, channelization of
an adjoining waterway, deposition of dredged material, and
excavation for ports and marinas.
MANAGEMENT MEASURES SUMMARY
THE PROTECTION OF WETLANDS AND RIPARIAN AREAS — The purpose of this
management measure is to maintain the water quality benefits of
wetlands and riparian areas and to ensure that they do not in turn
become a source of nonpoint pollution due to degradation. Wetlands
and riparian zones reduce nonpoint source pollution by filtering out
of solution NPS-related contaminants such as phosphorus and
nitrogen. The ability of wetlands and riparian zones to perform
this function is determined by the vegetative composition,
geochemistry, and faunal species composition. Any changes to these
characteristics could affect filtering capacities.
THE RESTORATION OF WETLANDS AND RIPARIAN AREAS — This measure
promotes the restoration of preexisting wetland and riparian areas
where the restoration of such systems will have a significant
nonpoint source pollution abatement unction. This measure is
intended to address the increase in pollutant loadings that can
result from degradation or destruction of wetlands and riparian
areas. These areas are effective in removing several pollutants
from stormwater, such as sediment, nitrogen, and phosphorus.
Wetland and riparian areas also help to attenuate flows from
higher-than-average storm events, thereby protecting downstream
areas from impacts such as channel scour, streambank erosion, and
fluctuations in temperature and chemical characteristics. This can
be accomplished by reestablishing previous hydrologic dynamics,
vegetation, and structural characteristics.
ENGINEERED VEGETATED TREATMENT SYSTEMS — The purpose of vegetated
filter strips is to remove sediment and other pollutants from runoff
and wastewater by filtration, deposition, infiltration, absorption,
adsorption, decomposition, and volatilization, thereby reducing the
amount of pollution entering adjacent waterbodies. The ability of
a wetland to act as a sink for phosphorus and the ability to convert
nitrate to nitrogen gas through denitrification are two examples of
the important NPS pollution abatement functions performed by
constructed wetlands. This measure promotes the development of
artificial wetlands or vegetated treatment systems where these
systems will serve a nonpoint source pollution abatement function.
Chapter 8: Monitoring and Tracking Techniques to Accompany Management Measures
I. Introduction
II. Techniques for Assessing Water Quality and for Estimating Pollutant Loads
A. Nature and Scope of Nonpoint Source Problems
B. Monitoring Objectives
1. Section 6217 Objectives
2. Formulating Monitoring Objectives
C. Monitoring Approaches
1. General
2. Understanding the System to Be Monitored
3. Experimental Design
4. Site Locations
5. Sampling Frequency and Interval
6. Load Versus Water Quality Status Monitoring
7. Paramater Selection
8. Sampling Techniques
9. Quality Assurance and Quality Control
D. Data Needs
E. Statistical Considerations
1. Variability and Uncertainty
2. Samples and Sampling
3. Estimation and Hypothesis Testing
F. Data Analysis
III. Techniques and Procedures for Assessing Implementation, Operation, and Maintainance of Management Measures
A. Overview
B. Techniques
1. Implentation
2. Operation and Maintainance
IV. References
Chapter 2: Management Measures for Agricultural Sources – I. Introduction
I. INTRODUCTION
A. What “Management Measures” Are
This chapter specifies management measures to protect coastal waters from agricultural sources of nonpoint pollution. “Management measures” are defined in section 6217 of the Coastal Zone Act Reauthorization Amendments of 1990 (CZARA) as economically achievable measures to control the addition of pollutants to our coastal waters, which reflect the greatest degree of pollutant reduction achievable through the application of the best available nonpoint pollution control practices, technologies, processes, siting criteria, operating methods, or other alternatives.
These management measures will be incorporated by States into their coastal nonpoint programs, which under CZARA are to provide for the implementation of management measures that are “in conformity” with this guidance. Under CZARA, States are subject to a number of requirements as they develop and implement their Coastal Nonpoint Pollution Control Programs in conformity with this guidance and will have some flexibility in doing so. The application of these management measures by States to activities causing nonpoint pollution is described more fully in Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance, published jointly by the U.S. Environmental Protection Agency (EPA) and the National Oceanic and Atmospheric Administration (NOAA).
B. What “Management Practices” Are
In addition to specifying management measures, this chapter also lists and describes management practices for illustrative purposes only. While State programs are required to specify management measures in conformity with this guidance, State programs need not specify or require the implementation of the particular management practices described in this document. However, as a practical matter, EPA anticipates that States the management measures generally will be implemented by applying one or more management practices appropriate to the source, location, and climate. The practices listed in this document have been found by EPA to be representative of the types of practices that can be applied successfully to achieve the management measures. EPA has also used some of these practices, or appropriate combinations of these practices, as a basis for estimating the effectiveness, costs, and economic impacts of achieving the management measures. (Economic impacts of the management measures are addressed in a separate document entitled Economic Impacts of EPA Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters.)
EPA recognizes that there is often site-specific, regional and national variability in the selection of appropriate practices, as well as in the design constraints and pollution control effectiveness of practices. The list of practices for each management measure is not all-inclusive and does not preclude States or local agencies from using other technically sound practices. In all cases, however, the practice or set of practices chosen by a State needs to achieve the management measure.
C. Scope of This Chapter
This chapter addresses six categories of sources of agricultural nonpoint pollution that affect coastal waters:
1. Erosion from cropland;
2. Confined animal facilities;
3. The application of nutrients to cropland;
4. The application of pesticides to cropland;
5. Grazing management; and
6. Irrigation of cropland.
Each category of sources (with the exception of confined animal facilities, which has two management measures) is addressed in a separate section of this guidance. Each section contains (1) the management measure; (2) an applicability statement that describes, when appropriate, specific activities and locations for which the measure is suitable; (3) a description of the management measure’s purpose; (4) the basis for the management measure’s selection; (5) information on the effectiveness of the management measure and/or of practices to achieve the measure; (6) information on management practices that are suitable, either alone or in combination with other practices, to achieve the management measure; and (7) information on costs of the measure and/or practices to achieve the measure.
D. Relationship of This Chapter to Other Chapters and to Other EPA Documents
1. Chapter 1 of this document contains detailed information on the legislative background for this guidance, the process used by EPA to develop this guidance, and the technical approach used by EPA in the guidance.
2. Chapter 7 of this document contains management measures to protect wetlands and riparian areas that serve a nonpoint source abatement function. These measures apply to a broad variety of sources, including agricultural sources.
3. Chapter 8 of this document contains information on recommended monitoring techniques (1) to ensure proper implementation, operation, and maintenance of the management measures and (2) to assess over time the success of the measures in reducing pollution loads and improving water quality.
4. EPA has separately published a document entitled Economic Impacts of EPA Guidance Specifying Management Measures for Sources of Nonpoint Pollution in Coastal Waters.
5. NOAA and EPA have jointly published guidance entitled Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance. This guidance contains details on how State Coastal Nonpoint Pollution Control Programs are to be developed by States and approved by NOAA and EPA. It includes guidance on the following:>
* The basis and process for EPA/NOAA approval of state Coastal Nonpoint Pollution Control Programs;
* How NOAA and EPA expect State programs to provide for the implementation of management measures “in conformity” with this management measures guidance;
* How States may target sources in implementing their Coastal Nonpoint Pollution Control Programs;
* Changes in State coastal boundaries; and
* Requirements concerning how States are to implement the Coastal Nonpoint Pollution Control Programs.
E. Coordination of Measures
The management measures developed for agriculture are to be used as an overall system of measures to address nonpoint source (NPS) pollution sources on any given site. In most cases, not all of the measures will be needed to address the nonpoint sources at a specific site. For example, many farms or agriculture enterprises do not have animals as part of the enterprise and would not need to be concerned with the management measures that address confined animal facilities or grazing. By the same token, many enterprises do not use irrigation and would not need to use the irrigation water management measure.
Most enterprises will have more than one source to address and may need to employ two or more of the measures to address the multiple sources. Where more than one source exists, the application of the measures is to be coordinated to produce an overall system that adequately addresses all sources for the site in a cost-effective manner.
The agricultural management measures for CZMA are, for the most part, systems of practices that are commonly used and recommended by the U.S. Department of Agriculture (USDA) as components of Resource Management Systems, Water Quality Management Plans, and Agricultural Waste Management Systems. Practices and plans installed under State NPS programs are also included. Many farms and fields, therefore, may already be in compliance with the measures needed to address the nonpoint sources on them. For cases where existing source control is inadequate to achieve conformity with the needed management measures, it may be necessary to add only one or two more practices to achieve conformity. Existing NPS progress must be recognized and appropriate credit given to the accomplishment of our common goal to control NPS pollution. There is no need to spend additional resources for a practice that is already in existence and operational. Existing practices, plans, and systems should be viewed as building blocks for these management measures and may need no additional improvement.
F. Pollutants That Cause Agricultural Nonpoint Source Pollution
The primary agricultural nonpoint source pollutants are nutrients, sediment, animal wastes, salts, and pesticides. Agricultural activities also have the potential to directly impact the habitat of aquatic species through physical disturbances caused by livestock or equipment, or through the management of water. The general pathways for transport of pollutants from agricultural lands to water resources are shown in Figure 2-1 (USDA, 1991). The effects of these pollutants on water quality are discussed below.
1. Nutrients
Nitrogen (N) and phosphorus (P) are the two major nutrients from agricultural land that degrade water quality. Nutrients are applied to agricultural land in several different forms and come from various sources, including;
* Commercial fertilizer in a dry or fluid form, containing nitrogen (N), phosphorus (P), potassium (K), secondary nutrients, and micronutrients;
* Manure from animal production facilities including bedding and other wastes added to the manure, containing N,P,K, secondary nutrients, micronutrients, salts, some metals, and organics;
* Municipal and industrial treatment plant sludge, containing N,P,K, secondary nutrients, micronutrients, salts, metals, and organic solids;
* Municipal and industrial treatment plant effluent, containing N,P,K, secondary nutrients, micronutrients, salts, metals, and organics;
* Legumes and crop residues containing N, P, K, secondary nutrients, and micronutrients;
* Irrigation water; and
* Atmospheric deposition of nutrients such as nitrogen and sulphur.
Surface water runoff from agricultural lands to which nutrients have been applied may transport the following pollutants:
* Particulate-bound nutrients, chemicals, and metals, such as phosphorus, organic nitrogen, and metals applied with some organic wastes;
* Soluble nutrients and chemicals, such as nitrogen, phosphorus, metals, and many other major and minor nutrients;
* Sediment, particulate organic solids, and oxygen-demanding material;
* Salts; and
* Bacteria, viruses, and other microorganisms.
Ground-water infiltration from agricultural lands to which nutrients have been applied may transport the following pollutants: soluble nutrients and chemicals, such as nitrogen, phosphorus, metals, and many other major and minor nutrients, and salts.
Surface water and ground-water pollutants from organic matter and crop residue decomposition and from legumes growing on agricultural land may include nitrogen, phosphorus, and other essential nutrients found in the residue of growing crops.
All plants require nutrients for growth. In aquatic environments, nutrient availability usually limits plant growth. Nitrogen and phosphorus generally are present at background or natural levels below 0.3 and 0.05 mg/L, respectively. When these nutrients are introduced into a stream, lake, or estuary at higher rates, aquatic plant productivity may increase dramatically. This process, referred to as cultural eutrophication, may adversely affect the suitability of the water for other uses.
Increased aquatic plant productivity results in the addition to the system of more organic material, which eventually dies and decays. The decaying organic matter produces unpleasant odors and depletes the oxygen supply required by aquatic organisms. Excess plant growth may also interfere with recreational activities such as swimming and boating. Depleted oxygen levels, especially in colder bottom waters where dead organic matter tends to accumulate, can reduce the quality of fish habitat and encourage the propagation of fish that are adapted to less oxygen or to warmer surface waters. Highly enriched waters will stimulate algae production, with consequent increased turbidity and color. Algae growth is also believed to be harmful to coral reefs (e.g., Florida coast). Furthermore, the increased turbidity results in less sunlight penetration and availability to submerged aquatic vegetation (SAV). Since SAV provides habitat for small or juvenile fish, the loss of SAV has severe consequences for the food chain. Chesapeake Bay is an example in which nutrients are believed to have contributed to SAV loss.
a. Nitrogen
All forms of transported nitrogen are potential contributors to eutrophication in lakes, estuaries, and some coastal waters. In general, though not in all cases, nitrogen availability is the limiting factor for plant growth in marine ecosystems. Thus, the addition of nitrogen can have a significant effect on the natural functioning of marine ecosystems.
In addition to eutrophication, excessive nitrogen causes other water quality problems. Dissolved ammonia at concentrations above 0.2 mg/L may be toxic to fish, especially trout. Nitrates in drinking water are potentially dangerous, especially to newborn infants. Nitrate is converted to nitrite in the digestive tract, which reduces the oxygen-carrying capacity of the blood (methemoglobinemia), resulting in brain damage or even death. The U.S. Environmental Protection Agency has set a limit of 10 mg/L nitrate-nitrogen in water used for human consumption (USEPA, 1989).
Nitrogen is naturally present in soils but must be added to increase crop production. Nitrogen is added to the soil primarily by applying commercial fertilizers and manure, but also by growing legumes (biological nitrogen fixation) and incorporating crop residues. Not all nitrogen that is present in or on the soil is available for plant use at any one time. For example, in the eastern Corn Belt, it is normally assumed that about 50 percent of applied N is assimilated by crops during the year of application (Nelson, 1985). Organic nitrogen normally constitutes the majority of the soil nitrogen. It is slowly converted (2 to 3 percent per year) to the more readily plant-available inorganic ammonium or nitrate.
The chemical form of nitrogen affects its impact on water quality. The most biologically important inorganic forms of nitrogen are ammonium (NH4-N), nitrate (NO3-N), and nitrite (NO2-N). Organic nitrogen occurs as particulate matter, in living organisms, and as detritus. It occurs in dissolved form in compounds such as amino acids, amines, purines, and urea.
Nitrate-nitrogen is highly mobile and can move readily below the crop root zone, especially in sandy soils. It can also be transported with surface runoff, but not usually in large quantities. Ammonium, on the other hand, becomes adsorbed to the soil and is lost primarily with eroding sediment. Even if nitrogen is not in a readily available form as it leaves the field, it can be converted to an available form either during transport or after delivery to waterbodies.
b. Phosphorus
Phosphorus can also contribute to the eutrophication of both freshwater and estuarine systems. While phosphorus typically plays the controlling role in freshwater systems, in some estuarine systems both nitrogen and phosphorus can limit plant growth. Algae consume dissolved inorganic phosphorus and convert it to the organic form. Phosphorus is rarely found in concentrations high enough to be toxic to higher organisms.
Although the phosphorus content of most soils in their natural condition is low, between 0.01 and 0.2 percent by weight, recent soil test results show that the phosphorus content of most cropped soils in the Northeast have climbed to the high or very high range (Sims, 1992). Manure and fertilizers increase the level of available phosphorus in the soil to promote plant growth, but many soils now contain higher phosphorus levels than plants need (Killorn, 1980; Novais and Kamprath, 1978). Phosphorus can be found in the soil in dissolved, colloidal, or particulate forms.
Runoff and erosion can carry some of the applied phosphorus to nearby water bodies. Dissolved inorganic phosphorus (orthophosphate phosphorus) is probably the only form directly available to algae. Particulate and organic phosphorus delivered to waterbodies may later be released and made available to algae when the bottom sediment of a stream becomes anaerobic, causing water quality problems.
2. Sediment
Sediment affects the use of water in many ways. Suspended solids reduce the amount of sunlight available to aquatic plants, cover fish spawning areas and food supplies, smother coral reefs, clog the filtering capacity of filter feeders, and clog and harm the gills of fish. Turbidity interferes with the feeding habits of fish. These effects combine to reduce fish, shellfish, coral, and plant populations and decrease the overall productivity of lakes, streams, estuaries, and coastal waters. In addition, recreation is limited because of the decreased fish population and the water’s unappealing, turbid appearance. Turbidity also reduces visibility, making swimming less safe.
Chemicals such as some pesticides, phosphorus, and ammonium are transported with sediment in an adsorbed state. Changes in the aquatic environment, such as a lower concentration in the overlying waters or the development of anaerobic conditions in the bottom sediments, can cause these chemicals to be released from the sediment. Adsorbed phosphorus transported by the sediment may not be immediately available for aquatic plant growth but does serve as a long-term contributor to eutrophication.
Sediment is the result of erosion. It is the solid material, both mineral and organic, that is in suspension, is being transported, or has been moved from its site of origin by air, water, gravity, or ice. The types of erosion associated with agriculture that produce sediment are (1) sheet and rill erosion and (2) gully erosion. Soil erosion can be characterized as the transport of particles that are detached by rainfall, flowing water, or wind (Figure 2-2). Eroded soil is either redeposited on the same field or transported from the field in runoff.
Sediments from different sources vary in the kinds and amounts of pollutants that are adsorbed to the particles. For example, sheet and rill erosion mainly move soil particles from the surface or plow layer of the soil. Sediment that originates from surface soil has a higher pollution potential than that from subsurface soils. The topsoil of a field is usually richer in nutrients and other chemicals because of past fertilizer and pesticide applications, as well as nutrient cycling and biological activity. Topsoil is also more likely to have a greater percentage of organic matter. Sediment from gullies and streambanks usually carries less adsorbed pollutants than sediment from surface soils.
Soil eroded and delivered from cropland as sediment usually contains a higher percentage of finer and less dense particles than the parent soil on the cropland. This change in composition of eroded soil is due to the selective nature of the erosion process. For example, larger particles are more readily detached from the soil surface because they are less cohesive, but they also settle out of suspension more quickly because of their size. Organic matter is not easily detached because of its cohesive properties, but once detached it is easily transported because of its low density. Clay particles and organic residues will remain suspended for longer periods and at slower flow velocities than will larger or more dense particles. This selective erosion can increase overall pollutant delivery per ton of sediment delivered because small particles have a much greater adsorption capacity than larger particles. As a result, eroding sediments generally contain higher concentrations of phosphorus, nitrogen, and pesticides than the parent soil (i.e., they are enriched).
3. Animal Wastes
Animal waste (manure) includes the fecal and urinary wastes of livestock and poultry; process water (such as from a milking parlor); and the feed, bedding, litter, and soil with which they become intermixed. The following pollutants may be contained in manure and associated bedding materials and could be transported by runoff water and process wastewater from confined animal facilities:
* Oxygen-demanding substances;
* Nitrogen, phosphorus, and many other major and minor nutrients or other deleterious materials;
* Organic solids;
* Salts;
* Bacteria, viruses, and other microorganisms; and
* Sediments.
Fish kills may result from runoff, wastewater, or manure entering surface waters, due to ammonia or dissolved oxygen depletion. The decomposition of organic materials can deplete dissolved oxygen supplies in water, resulting in anoxic or anaerobic conditions. Methane, amines, and sulfide are produced in anaerobic waters, causing the water to acquire an unpleasant odor, taste, and appearance. Such waters can be unsuitable for drinking, fishing, and other recreational uses.
Solids deposited in waterbodies can accelerate eutrophication through the release of nutrients over extended periods of time. Because of the high nutrient and salt content of manure and runoff from manure-covered areas, contamination of ground water can be a problem if storage structures are not built to minimize seepage.
Animal diseases can be transmitted to humans through contact with animal feces. Runoff from fields receiving manure will contain extremely high numbers of bacteria if the manure has not been incorporated or the bacteria have not been subject to stress. Shellfish closure and beach closure can result from high fecal coliform counts. Although not the only source of pathogens, animal waste has been responsible for shellfish contamination in some coastal waters.
The method, timing, and rate of manure application are significant factors in determining the likelihood that water quality contamination will result. Manure is generally more likely to be transported in runoff when applied to the soil surface than when incorporated into the soil. Spreading manure on frozen ground or snow can result in high concentrations of nutrients being transported from the field during rainfall or snowmelt, especially when the snowmelt or rainfall events occur soon after spreading (Robillard and Walter, 1986). The water quality problems associated with nitrogen and phosphorus are discussed under Section F.1.
When application rates of manure for crop production are based on N, the P and K rates normally exceed plant requirements (Westerman et al., 1985). The soil generally has the capacity to adsorb phosphorus leached from manure applied on land. As previously mentioned, however, nitrates are easily leached through soil into ground water or to return flows, and phosphorus can be transported by eroded soil.
Conditions that cause a rapid die-off of bacteria are low soil moisture, low pH, high temperatures, and direct solar radiation. Manure storage generally promotes die-off, although pathogens can remain dormant at certain temperatures. Composting the wastes can be quite effective in decreasing the number of pathogens.
4. Salts
Salts are a product of the natural weathering process of soil and geologic material. They are present in varying degrees in all soils and in fresh water, coastal waters, estuarine waters, and ground waters.
In soils that have poor subsurface drainage, high salt concentrations are created within the root zone where most water extraction occurs. The accumulation of soluble and exchangeable sodium leads to soil dispersion, structure breakdown, decreased infiltration, and possible toxicity; thus, salts often become a serious problem on irrigated land, both for continued agricultural production and for water quality considerations. High salt concentrations in streams can harm freshwater aquatic plants just as excess soil salinity damages agricultural crops. While salts are generally a more significant pollutant for freshwater ecosystems than for saline ecosystems, they may also adversely affect anadromous fish. Although they live in coastal and estuarine waters most of their lives, anadromous fish depend on freshwater systems near the coast for crucial portions of their life cycles.
The movement and deposition of salts depend on the amount and distribution of rainfall and irrigation, the soil and underlying strata, evapotranspiration rates, and other environmental factors. In humid areas, dissolved mineral salts have been naturally leached from the soil and substrata by rainfall. In arid and semi-arid regions, salts have not been removed by natural leaching and are concentrated in the soil. Soluble salts in saline and sodic soils consist of calcium, magnesium, sodium, potassium, carbonate, bicarbonate, sulfate, and chloride ions. They are fairly easily leached from the soil. Sparingly soluble gypsum and lime also occur in amounts ranging from traces to more than 50 percent of the soil mass.
Irrigation water, whether from ground or surface water sources, has a natural base load of dissolved mineral salts. As the water is consumed by plants or lost to the atmosphere by evaporation, the salts remain and become concentrated in the soil. This is referred to as the “concentrating effect.”
The total salt load carried by irrigation return flow is the sum of the salt remaining in the applied water plus any salt picked up from the irrigated land. Irrigation return flows provide the means for conveying the salts to the receiving streams or ground-water reservoirs. If the amount of salt in the return flow is low in comparison to the total stream flow, water quality may not be degraded to the extent that use is impaired. However, if the process of water diversion for irrigation and the return of saline drainage water is repeated many times along a stream or river, water quality will be progressively degraded for downstream irrigation use as well as for other uses.
5. Pesticides
The term pesticide includes any substance or mixture of substances intended for preventing, destroying, repelling, or mitigating any pest or intended for use as a plant regulator, defoliant, or desiccant. The principal pesticidal pollutants that may be detected in surface water and in ground water are the active and inert ingredients and any persistent degradation products. Pesticides and their degradation products may enter ground and surface water in solution, in emulsion, or bound to soil colloids. For simplicity, the term pesticides will be used to represent “pesticides and their degradation products” in the following sections.
Despite the documented benefits of using pesticides (insecticides, herbicides, fungicides, miticides, nematicides, etc.) to control plant pests and enhance production, these chemicals may, in some instances, cause impairments to the uses of surface water and ground water. Some types of pesticides are resistant to degradation and may persist and accumulate in aquatic ecosystems.
Pesticides may harm the environment by eliminating or reducing populations of desirable organisms, including endangered species. Sublethal effects include the behavioral and structural changes of an organism that jeopardize its survival. For example, certain pesticides have been found to inhibit bone development in young fish or to affect reproduction by inducing abortion.
Herbicides in the aquatic environment can destroy the food source for higher organisms, which may then starve. Herbicides can also reduce the amount of vegetation available for protective cover and the laying of eggs by aquatic species. Also, the decay of plant matter exposed to herbicide-containing water can cause reductions in dissolved oxygen concentration (North Carolina State University, 1984).
Sometimes a pesticide is not toxic by itself but is lethal in the presence of other pesticides. This is referred to as a synergistic effect, and it may be difficult to predict or evaluate. Bioconcentration is a phenomenon that occurs if an organism ingests more of a pesticide than it excretes. During its lifetime, the organism will accumulate a higher concentration of that pesticide than is present in the surrounding environment. When the organism is eaten by another animal higher in the food chain, the pesticide will then be passed to that animal, and on up the food chain to even higher level animals.
A major source of contamination from pesticide use is the result of normal application of pesticides. Other sources of pesticide contamination are atmospheric deposition, spray drift during the application process, misuse, and spills, leaks, and discharges that may be associated with pesticide storage, handling, and waste disposal.
The primary routes of pesticide transport to aquatic systems are (Maas et al., 1984):
1. Direct application;
2. In runoff;
3. Aerial drift;
4. Volatilization and subsequent atmospheric deposition; and
5. Uptake by biota and subsequent movement in the food web.
The amount of field-applied pesticide that leaves a field in the runoff and enters a stream primarily depends on:
1. The intensity and duration of rainfall or irrigation;
2. The length of time between pesticide application and rainfall occurrence;
3. The amount of pesticide applied and its soil/water partition coefficient;
4. The length and degree of slope and soil composition;
5. The extent of exposure to bare (vs. residue or crop-covered) soil;
6. Proximity to streams;
7. The method of application; and
8. The extent to which runoff and erosion are controlled with agronomic and structural practices.
Pesticide losses are generally greatest when rainfall is intense and occurs shortly after pesticide application, a condition for which water runoff and erosion losses are also greatest.
The rate of pesticide movement through the soil profile to ground water is inversely proportional to the pesticide adsorption partition coefficient or Kd (a measure of the degree to which a pesticide is partitioned between the soil and water phase). The larger the Kd, the slower the movement and the greater the quantity of water required to leach the pesticide to a given depth.
Pesticides can be transported to receiving waters either in dissolved form or attached to sediment. Dissolved pesticides may be leached to ground-water supplies. Both the degradation and adsorption characteristics of pesticides are highly variable.
6. Habitat Impacts
The functioning condition of riparian-wetland areas is a result of interaction among geology, soil, water, and vegetation. Riparian-wetland areas are functioning properly when adequate vegetation is present to (1) dissipate stream energy associated with high water flows, thereby reducing erosion and improving water quality; (2) filter sediment and aid floodplain development; (3) support denitrification of nitrate-contaminated ground water as it is discharged into streams; (4) improve floodwater retention and ground-water recharge; (5) develop root masses that stabilize banks against cutting action; (6) develop diverse ponding and channel characteristics to provide the habitat and the water depth, duration, and temperature necessary for fish production, waterfowl breeding, and other uses; and (7) support greater biodiversity.
Improper livestock grazing affects all four components of the water-riparian system: banks/shores, water column, channel, and aquatic and bordering vegetation (Platts, 1990). The potential effects of grazing include:
Shore/banks
* Shear or sloughing of streambank soils by hoof or head action.
* Water, ice, and wind erosion of exposed streambank and channel soils because of loss of vegetative cover.
* Elimination or loss of streambank vegetation.
* Reduction of the quality and quantity of streambank undercuts.
* Increasing streambank angle (laying back of streambanks), which increases water width, decreases stream depth, and alters or eliminates fish habitat.
Water Column
* Withdrawal from streams to irrigate grazing lands.
* Drainage of wet meadows or lowering of the ground-water table to facilitate grazing access.
* Pollutants (e.g., sediments) in return water from grazed lands, which are detrimental to the designated uses such as fisheries.
* Changes in magnitude and timing of organic and inorganic energy (i.e., solar radiation, debris, nutrients) inputs to the stream.
* Increase in fecal contamination.
* Changes in stream morphology, such as increases in stream width and decreases in stream depth, including reduction of stream shore water depth.
* Changes in timing and magnitude of stream flow events from changes in watershed vegetative cover.
* Increase in stream temperature.
Channel
* Changes in channel morphology.
* Altered sediment transport processes.
Riparian Vegetation
* Changes in plant species composition (e.g., shrubs to grass to forbs).
* Reduction of floodplain and streambank vegetation including vegetation hanging over or entering into the water column.
* Decrease in plant vigor.
* Changes in timing and amounts of organic energy leaving the riparian zone.
* Elimination of riparian plant communities (i.e., lowering of the water table allowing xeric plants to replace riparian plants).
II. MANAGEMENT MEASURES FOR AGRICULTURAL SOURCES
A. Erosion and Sediment Control Management Measure
Apply the erosion component of a Conservation Management System (CMS) as defined in the Field Office Technical Guide of the U.S. Department of Agriculture – Soil Conservation Service (see Appendix 2A of this chapter) to minimize the delivery of sediment from agricultural lands to surface waters, or
Design and install a combination of management and physical practices to settle the settleable solids and associated pollutants in runoff delivered from the contributing area for storms of up to and including a 10-year, 24-hour frequency.
1. Applicability
This management measure is intended to be applied by States to activities that cause erosion on agricultural land and on land that is converted from other land uses to agricultural lands. Agricultural lands include:
* Cropland;
* Irrigated cropland;
* Range and pasture;
* Orchards;
* Permanent hayland;
* Specialty crop production; and
* Nursery crop production.
Under the Coastal Zone Act Reauthorization Amendments of 1990, States are subject to a number of requirements as they develop coastal nonpoint programs in conformity with this measure and will have some flexibility in doing so. The application of management measures by States is described more fully in Coastal Nonpoint Pollution Control Program: Program Development and Approval Guidance, published jointly by the U.S. Environmental Protection Agency (EPA) and the National Oceanic and Atmospheric Administration (NOAA) of the U.S. Department of Commerce.
2. Description
The problems associated with soil erosion are the movement of sediment and associated pollutants by runoff into a waterbody. See Section I.F.2 of this chapter for additional information regarding problems.
Application of this management measure will reduce the mass load of sediment reaching a waterbody and improve water quality and the use of the water resource. The measure can be implemented by using one of two different strategies or a combination of both. The first, and most desirable, strategy would be to implement practices on the field that would prevent erosion and the transport of sediment from the field. Practices that could be used to accomplish this are conservation tillage, contour strip-cropping, terraces, and critical area planting.
The second strategy is to route runoff from fields through practices that remove sediment. Practices that could be used to accomplish this are filter strips, field borders, grade stabilization structures, sediment retention ponds, water and sediment control basins, and terraces. Site conditions will dictate the appropriate combination of practices for any given situation.
Conservation management systems (CMS) include any combination of conservation practices and management that achieves a level of treatment of the five natural resources (i.e., soil, water, air, plants, and animals) that satisfies criteria contained in the Soil Conservation Service (SCS) Field Office Technical Guide (FOTG), such as a resource management system (RMS) or an acceptable management system (AMS). These criteria are developed at the State level, with concurrence by the appropriate SCS National Technical Center (NTC). The criteria are then applied in the provision of field office technical assistance, under the direction of the District Conservationist of SCS. In-state coordination of FOTG use is provided by the Area Conservationist and State Conservationist of SCS.
The erosion component of a CMS addresses sheet and rill erosion, wind erosion, concentrated flow, streambank erosion, soil mass movements, road bank erosion, construction site erosion, and irrigation-induced erosion. National (minimum) criteria pertaining to erosion and sediment control under an RMS will be applied to prevent long-term soil degradation and to resolve existing or potential off-site deposition problems. National criteria pertaining to the water resource will be applied to control sediment movement to minimize contamination of receiving waters. The combined effects of these criteria will be to both reduce upland soil erosion and minimize sediment delivery to receiving waters.
The practical limits of resource protection under a CMS within any given area are determined through the application of national social, cultural, and economic criteria. With respect to economics, landowners will not be required to implement an RMS if the system is generally too costly for landowners. Instead, landowners may be required to implement a less costly, and less protective, AMS. In some cases, landowner constraints may be such that an RMS or AMS cannot be implemented quickly. In these situations, a “progressive planning approach” may be used to ultimately achieve planning and application of an RMS or AMS. Progressive planning is the incremental process of building a plan on part or all of the planning unit over a period of time. For additional details regarding CMS, RMS, and AMS, see Appendix 2A of this chapter.
It is recognized that implementation of this measure may increase the potential for movement of water and soluble pollutants through the soil profile to the ground water. It is not the intent of this measure to address a surface water problem at the expense of ground water. Erosion and sediment control systems can and should be designed to protect against the contamination of ground water. Ground-water protection will also be provided through implementation of the nutrient and pesticide management measures to reduce and control the application of nutrients and pesticides.
Operation and Maintenance
Continued performance of this measure will be ensured through supporting maintenance operations where appropriate. Since practices are designed to control a specific storm frequency, they may suffer damage when larger storms occur. It is expected that damage will be repaired after such storms and that practices will be inspected periodically. To ensure that practices selected to implement this measure will continue to function as designed and installed, some operational functions and maintenance will be necessary over the life of the practices.
Most structural practices for erosion and sediment control are designed to operate without human intervention. Management practices such as conservation tillage, however, do require “operation consideration” each time they are used. Field operations should be conducted with such practices in mind to ensure that they are not damaged or destroyed by the operations. For example, herbicides should not be applied to any practice that uses a permanent vegetative cover, such as waterways and filter strips.
Structural practices such as diversions, grassed waterways, and other practices that require grading and shaping may require repair to maintain the original design; reseeding may also be needed to maintain the original vegetative cover. Trees and brush should not be allowed to grow on berms, dams, or other structural embankments. Cleaning of sediment retention basins will be needed to maintain their original design capacity and efficiency.
Filter strips and field borders must be maintained to prevent channelization of flow and the resulting short-circuiting of filtering mechanisms. Reseeding of filter strips may be required on a frequent basis.
3. Management Measure Selection
This management measure was selected based on an evaluation of available information that documents the beneficial effects of improved erosion and sediment control (see Section II.A.4 of this chapter). Specifically, the available information shows that erosion control practices can be used to greatly reduce the quantity of eroding soil on agricultural land, and that edge-of-field practices can effectively remove sediment from runoff before it leaves agricultural lands. The benefits of this management measure include significant reductions in the mass load of sediment and associated pollutants (e.g., phosphorus, some pesticides) entering waterbodies. By reducing the load of sediment leaving a field, downstream water uses can be maintained and improved.
Two options are provided under this management measure that represent best available technology for minimizing the delivery of sediment from agricultural lands to receiving waters. Different management strategies, are employed, however, with the options. The most desirable option is “(1)” since it not only minimizes the delivery of sediment to receiving waters, but also reduces erosion to provide an agronomic benefit. Option “(2)” minimizes the delivery of sediment to receiving waters, but does not necessarily provide the agronomic benefits of upland erosion control. By providing these two options, States are given the flexibility to address erosion and sediment problems in a manner that best reflects State and local needs and preferences.
By designing the measure to achieve contaminant load reduction objectives, the necessary mix of structural and management practices for a given site should not result in undue economic impact on the operator. Many of the practices that could be used to implement this measure may already be required by Federal, State, or local rules (e.g., filter strips or field borders along streams) or may otherwise be in use on agricultural fields. Since many producers may already be using systems that satisfy or partly satisfy the intent of this management measure, the only action that may be necessary will be to recognize the effectiveness of the existing practices and add additional practices, if needed. By building upon existing erosion and sediment control efforts, the time, effort, and cost of implementing this measure will be reduced.
4. Effectiveness Information
The effectiveness of management practices depends on several factors, including:
* The contaminant to be controlled;
* The types of practices or controls being considered; and
* Site-specific conditions.
Management practices or systems of practices must be designed for site-specific conditions to achieve desired effectiveness levels. Practice systems include combinations of practices that provide source control of the contaminant(s) as well as control or reductions in edge-of-field losses and delivery to receiving waters. Table 2-1 provides a gross estimate of practice effectiveness as reported in research literature. The actual effectiveness of a practice will depend exclusively on site-specific variables such as soil type, crop rotation, topography, tillage, and harvesting methods. Even within relatively small watersheds, extreme spatial and temporal variations are common. With this type of variation, the ranges of likely values associated with the reported observations in Table 2-1 are large.
The variability in the effectiveness of selected conservation practices that are frequently recommended by SCS in resource planning is illustrated in Table 2-2. This table can be used as a general guide for estimating the effects of these practices on water quality and quantity. The table references include additional site-specific information. Practice effects shown include changes in the water budget, sediment yield, and the movement of pesticides and nutrients. The impacts of variations in climate and soil conditions are accounted for to some extent through the presentation of effectiveness data for different soil-climate combinations. Data were not available for all soils and climates.
Data for the table were obtained from the research literature and include computer model simulation results. Values are reported as the percentage of change in the mass load of a given parameter that can be expected from installing the practice. Changes are determined versus a base condition of a rain-fed, nonleguminous, continuous, row crop (usually corn) that has been cultivated under conventional tillage.
Data from model studies are marked with an “M.” For example, -27M indicates that the load reduction estimate of 27 percent is derived from a model simulation. Data obtained from plot studies using rainfall simulators are marked with an “S.” For example, +15S indicates that the estimated load increase of 15 percent is based on a rainfall simulation study.
The range is reported in parentheses, followed by other reported values within the range, set off by commas. For example, (-32 to +10), -15, +5 denotes a range from a decrease of 32 percent to an increase of 10 percent, with intermediate reported changes of a 15 percent decrease and 5 percent increase. Some practices have a relatively wide range of values because of the variability in climate, soils, and management that occurs with these practices. Although some of the ranges are large, they can usually be attributed to small changes in very small quantities (thus the percentage change is great, yet the magnitude of change is small) or to the variability of site-specific conditions.
Table 2-2 contains the following information:
* Column (a) lists the practice and its SCS reporting code number.
* Column (b) lists the climate and a generalized soil classification for the site under consideration.
* Column (c) is the percentage change in surface runoff and deep percolation, components of the water budget, caused by the applied practice.
* Column (d) is the percentage change in sediment load caused by the applied practice.
* Column (e) is the percentage change in the phosphorus load. Two phases of phosphorus are considered: adsorbed and dissolved.
* Column (f) is the percentage change in the load of nitrogen in the adsorbed phase, nitrate in surface runoff, and nitrate in the leachate.
* Column (g) is the percentage change in the pesticide load. The phases of the pesticide listed are (1) strongly adsorbed in surface water, (2) weakly adsorbed in surface water, and (3) weakly adsorbed in the leachate.
5. Erosion and Sediment Control Management Practices
As discussed more fully at the beginning of this chapter and in Chapter 1, the following practices are described for illustrative purposes only. State programs need not require implementation of these practices. However, as a practical matter, EPA anticipates that the management measure set forth above generally will be implemented by applying one or more management practices appropriate to the source, location, and climate. The practices set forth below have been found by EPA to be representative of the types of practices that can be applied successfully to achieve the management measure described above.
Combinations of the following practices can be used to satisfy the requirements of this management measure. The SCS practice number and definition are provided for each management practice, where available. Also included in italics are SCS statements describing the effect each practice has on water quality (USDA-SCS, 1988).
* a. Conservation cover (327): Establishing and maintaining perennial vegetative cover to protect soil and water resources on land retired from agricultural production.
Agricultural chemicals are usually not applied to this cover in large quantities and surface and ground water quality may improve where these material are not used. Ground cover and crop residue will be increased with this practice. Erosion and yields of sediment and sediment related stream pollutants should decrease. Temperatures of the soil surface runoff and receiving water may be reduced. Effects will vary during the establishment period and include increases in runoff, erosion and sediment yield. Due to the reduction of deep percolation, the leaching of soluble material will be reduced, as will be the potential for causing saline seeps. Long-term effects of the practice would reduce agricultural nonpoint sources of pollution to all water resources.
* b. Conservation cropping sequence (328): An adapted sequence of crops designed to provide adequate organic residue for maintenance or improvement of soil tilth.
This practice reduces erosion by increasing organic matter, resulting in a reduction of sediment and associated pollutants to surface waters. Crop rotations that improve soil tilth may also disrupt disease, insect and weed reproduction cycles, reducing the need for pesticides. This removes or reduces the availability of some pollutants in the watershed. Deep percolation may carry soluble nutrients and pesticides to the ground water. Underlying soil layers, rock and unconsolidated parent material may block, delay, or enhance the delivery of these pollutants to ground water. The fate of these pollutants will be site specific, depending on the crop management, the soil and geologic conditions.
* c. Conservation tillage (329): Any tillage or planting system that maintains at least 30 percent of the soil surface covered by residue after planting to reduce soil erosion by water; or, where soil erosion by wind is the primary concern, maintains at least 1,000 pounds of flat, small-grain residue equivalent on the surface during the critical erosion period.
This practice reduces soil erosion, detachment and sediment transport by providing soil cover during critical times in the cropping cycle. Surface residues reduce soil compaction from raindrops, preventing soil sealing and increasing infiltration. This action may increase the leaching of agricultural chemicals into the ground water.
In order to maintain the crop residue on the surface it is difficult to incorporate fertilizers and pesticides. This may increase the amount of these chemicals in the runoff and cause more surface water pollution.
The additional organic material on the surface may increase the bacterial action on and near the soil surface. This may tie-up and then breakdown many pesticides which are surface applied, resulting in less pesticide leaving the field. This practice is more effective in humid regions.
With a no-till operation the only soil disturbance is the planter shoe and the compaction from the wheels. The surface applied fertilizers and chemicals are not incorporated and often are not in direct contact with the soil surface. This condition may result in a high surface runoff of pollutants (nutrient and pesticides). Macropores develop under a no-till system. They permit deep percolation and the transmittal of pollutants, both soluble and insoluble to be carried into the deeper soil horizons and into the ground water.
Reduced tillage systems disrupt or break down the macropores, incidentally incorporate some of the materials applied to the soil surface, and reduce the effects of wheeltrack compaction. The results are less runoff and less pollutants in the runoff.
* d. Contour farming (330): Farming sloping land in such a way that preparing land, planting, and cultivating are done on the contour. This includes following established grades of terraces or diversions.
This practice reduces erosion and sediment production. Less sediment and related pollutants may be transported to the receiving waters.
Increased infiltration may increase the transportation potential for soluble substances to the ground water.
* e. Contour orchard and other fruit area (331): Planting orchards, vineyards, or small fruits so that all cultural operations are done on the contour.
Contour orchards and fruit areas may reduce erosion, sediment yield, and pesticide concentration in the water lost. Where inward sloping benches are used, the sediment and chemicals will be trapped against the slope. With annual events, the bench may provide 100 percent trap efficiency. Outward sloping benches may allow greater sediment and chemical loss. The amount of retention depends on the slope of the bench and the amount of cover. In addition, outward sloping benches are subject to erosion form runoff from benches immediately above them. Contouring allows better access to rills, permitting maintenance that reduces additional erosion. Immediately after establishment, contour orchards may be subject to erosion and sedimentation in excess of the now contoured orchard. Contour orchards require more fertilization and pesticide application than did the native grasses that frequently covered the slopes before orchards were started. Sediment leaving the site may carry more adsorbed nutrients and pesticides than did the sediment before the benches were established from uncultivated slopes. If contoured orchards replace other crop or intensive land use, the increase or decrease in chemical transport from the site may be determined by examining the types and amounts of chemicals used on the prior land use as compared to the contour orchard condition.
Soluble pesticides and nutrients may be delivered to and possibly through the root zone in an amount proportional to the amount of soluble pesticides applied, the increase in infiltration, the chemistry of the pesticides, organic and clay content of the soil, and amounts of surface residues. Percolating water below the root zone may carry excess solutes or may dissolve potential pollutants as they move. In either case, these solutes could reach ground water supplies and/or surface downslope from the contour orchard area. The amount depends on soil type, surface water quality, and the availability of soluble material (natural or applied).
* f. Cover and green manure crop (340): A crop of close-growing grasses, legumes, or small grain grown primarily for seasonal protection and soil improvement. It usually is grown for 1 year or less, except where there is permanent cover as in orchards.
Erosion, sediment and adsorbed chemical yields could be decreased in conventional tillage systems because of the increased period of vegetal cover. Plants will take up available nitrogen and prevent its undesired movement. Organic nutrients may be added to the nutrient budget reducing the need to supply more soluble forms. Overall volume of chemical application may decrease because the vegetation will supply nutrients and there may be allelopathic effects of some of the types of cover vegetation on weeds. Temperatures of ground and surface waters could slightly decrease.
* g. Critical area planting (342): Planting vegetation, such as trees, shrubs, vines, grasses, or legumes, on highly erodible or critically eroding areas (does not include tree planting mainly for wood products).
This practice may reduce soil erosion and sediment delivery to surface waters. Plants may take up more of the nutrients in the soil, reducing the amount that can be washed into surface waters or leached into ground water.
During grading, seedbed preparation, seeding, and mulching, large quantities of sediment and associated chemicals may be washed into surface waters prior to plant establishment.
* h. Crop residue use (344): Using plant residues to protect cultivated fields during critical erosion periods.
When this practice is employed, raindrops are intercepted by the residue reducing detachment, soil dispersion, and soil compaction. Erosion may be reduced and the delivery of sediment and associated pollutants to surface water may be reduced. Reduced soil sealing, crusting and compaction allows more water to infiltrate, resulting in an increased potential for leaching of dissolved pollutants into the ground water.
Crop residues on the surface increase the microbial and bacterial action on or near the surface. Nitrates and surface-applied pesticides may be tied-up and less available to be delivered to surface and ground water. Residues trap sediment and reduce the amount carried to surface water. Crop residues promote soil aggregation and improve soil tilth.
* i. Delayed seed bed preparation (354): Any cropping system in which all of the crop residue and volunteer vegetation are maintained on the soil surface until approximately 3 weeks before the succeeding crop is planted, thus shortening the bare seedbed period on fields during critical erosion periods.
The purpose is to reduce soil erosion by maintaining soil cover as long as practical to minimize raindrop splash and runoff during the spring erosion period. Other purposes include moisture conservation, improved water quality, increased soil infiltration, improved soil tilth, and food and cover for wildlife.
* j. Diversion (362): A channel constructed across the slope with a supporting ridge on the lower side (Figure 2-3).
This practice will assist in the stabilization of a watershed, resulting in the reduction of sheet and rill erosion by reducing the length of slope. Sediment may be reduced by the elimination of ephemeral and large gullies. This may reduce the amount of sediment and related pollutants delivered to the surface waters.
* k. Field border (386): A strip of perennial vegetation established at the edge of a field by planting or by converting it from trees to herbaceous vegetation or shrubs.
This practice reduces erosion by having perennial vegetation on an area of the field. Field borders serve as “anchoring points” for contour rows, terraces, diversions, and contour strip cropping. By elimination of the practice of tilling and planting the ends up and down slopes, erosion from concentrated flow in furrows and long rows may be reduced. This use may reduce the quantity of sediment and related pollutants transported to the surface waters.
* l. Filter strip (393): A strip or area of vegetation for removing sediment, organic matter, and other pollutants from runoff and wastewater.
Filter strips for sediment and related pollutants meeting minimum requirements may trap the coarser grained sediment. They may not filter out soluble or suspended fine-grained materials. When a storm causes runoff in excess When the field borders are located such that runoff flows across them in sheet flow, they may cause the deposition of sediment and prevent it from entering the surface water. Where these practice are between cropland and a stream or water body, the practice may reduce the amount of pesticide application drift from entering the surface water of the design runoff, the filter may be flooded and may cause large loads of pollutants to be released to the surface water. This type of filter requires high maintenance and has a relatively short service life and is effective only as long as the flow through the filter is shallow sheet flow.
Filter strips for runoff from concentrated livestock areas may trap organic material, solids, materials which become adsorbed to the vegetation or the soil within the filter. Often they will not filter out soluble materials. This type of filter is often wet and is difficult to maintain.
Filter strips for controlled overland flow treatment of liquid wastes may effectively filter out pollutants. The filter must be properly managed and maintained, including the proper resting time. Filter strips on forest land may trap coarse sediment, timbering debris, and other deleterious material being transported by runoff. This may improve the quality of surface water and has little effect on soluble material in runoff or on the quality of ground water.
All types of filters may reduce erosion on the area on which they are constructed.
Filter strips trap solids from the runoff flowing in sheet flow through the filter. Coarse-grained and fibrous materials are filtered more efficiently than fine-grained and soluble substances. Filter strips work for design conditions, but when flooded or overloaded they may release a slug load of pollutants into the surface water.
* m. Grade stabilization structure (410): A structure used to control the grade and head cutting in natural or artificial channels.
Where reduced stream velocities occur upstream and downstream from the structure, streambank and streambed erosion will be reduced. This will decrease the yield of sediment and sediment-attached substances. Structures that trap sediment will improve downstream water quality. The sediment yield change will be a function of the sediment yield to the structure, reservoir trap efficiency and of velocities of released water. Ground water recharge may affect aquifer quality depending on the quality of the recharging water. If the stored water contains only sediment and chemical with low water solubility, the ground water quality should not be affected.
* n. Grassed waterway (412): A natural or constructed channel that is shaped or graded to required dimensions and established in suitable vegetation for the stable conveyance of runoff.
This practice may reduce the erosion in a concentrated flow area, such as in a gully or in ephemeral gullies. This may result in the reduction of sediment and substances delivered to receiving waters. Vegetation may act as a filter in removing some of the sediment delivered to the waterway, although this is not the primary function of a grassed waterway.
Any chemicals applied to the waterway in the course of treatment of the adjacent cropland may wash directly into the surface waters in the case where there is a runoff event shortly after spraying.
When used as a stable outlet for another practice, waterways may increase the likelihood of dissolved and suspended pollutants being transported to surface waters when these pollutants are delivered to the waterway.
* o. Grasses and legumes in rotation (411): Establishing grasses and legumes or a mixture of them and maintaining the stand for a definite number of years as part of a conservation cropping system.
Reduced runoff and increased vegetation may lower erosion rates and subsequent yields of sediment and sediment-attached substances. Less applied nitrogen may be required to grow crops because grasses and legumes will supply organic nitrogen. During the period of the rotation when the grasses and legumes are growing, they will take up more phosphorus. Less pesticides may similarly be required with this practice. Downstream water temperatures may be lower depending on the season when this practice is applied. There will be a greater opportunity for animal waste management on grasslands because manures and other wastes may be applied for a longer part of the crop year.
* p. Sediment basins (350): Basins constructed to collect and store debris or sediment.
Sediment basins will remove sediment, sediment associated materials and other debris from the water which is passed on downstream. Due to the detention of the runoff in the basin, there is an increased opportunity for soluble materials to be leached toward the ground water.
* q. Contour stripcropping (585): Growing crops in a systematic arrangement of strips or bands on the contour to reduce water erosion.
The crops are arranged so that a strip of grass or close-growing crop is alternated with a strip of clean-tilled crop or fallow or a strip of grass is alternated with a close-growing crop (Figure 2-4).
This practice may reduce erosion and the amount of sediment and related substances delivered to the surface waters. The practice may increase the amount of water which infiltrates into the root zone, and, at the time there is an overabundance of soil water, this water may percolate and leach soluble substances into the ground water.
* r. Field strip-cropping (586): Growing crops in a systematic arrangement of strips or bands across the general slope (not on the contour) to reduce water erosion.
The crops are arranged so that a strip of grass or a close-growing crop is alternated with a clean-tilled crop or fallow.
This practice may reduce erosion and the delivery of sediment and related substances to the surface waters. The practice may increase infiltration and, when there is sufficient water available, may increase the amount of leachable pollutants moved toward the ground water.
Since this practice is not on the contour there will be areas of concentrated flow, from which detached sediment, adsorbed chemicals and dissolved substances will be delivered more rapidly to the receiving waters. The sod strips will not be efficient filter areas in these areas of concentrated flow.
* s. Terrace (600): An earthen embankment, a channel, or combination ridge and channel constructed across the slope (Figures 2-5 and 2-6).
This practice reduces the slope length and the amount of surface runoff which passes over the area downslope from an individual terrace. This may reduce the erosion rate and production of sediment within the terrace interval. Terraces trap sediment and reduce the sediment and associated pollutant content in the runoff water which enhance surface water quality. Terraces may intercept and conduct surface runoff at a nonerosive velocity to stable outlets, thus, reducing the occurrence of ephemeral and classic gullies and the resulting sediment. Increases in infiltration can cause a greater amount of soluble nutrients and pesticides to be leached into the soil. Underground outlets may collect highly soluble nutrient and pesticide leachates and convey runoff and conveying it directly to an outlet, terraces may increase the delivery of pollutants to surface waters. Terraces increase the opportunity to leach salts below the root zone in the soil. Terraces may have a detrimental effect on water quality if they concentrate and accelerate delivery of dissolved or suspended nutrient, salt, and pesticide pollutants to surface or ground waters.
* t. Water and sediment control basin (638): An earthen embankment or a combination ridge and channel generally constructed across the slope and minor watercourses to form a sediment trap and water detention basin.
The practice traps and removes sediment and sediment-attached substances from runoff. Trap control efficiencies for sediment and total phosphorus, that are transported by runoff, may exceed 90 percent in silt loam soils. Dissolved substances, such as nitrates, may be removed from discharge to downstream areas because of the increased infiltration. Where geologic condition permit, the practice will lead to increased loadings of dissolved substances toward ground water. Water temperatures of surface runoff, released through underground outlets, may increase slightly because of longer exposure to warming during its impoundment.
* u. Wetland and riparian zone protection
Wetland and riparian zone protection practices are described in Chapter 7.
6. Cost Information
Both national and selected State costs for a number of common erosion control practices are presented in Tables 2-3 through 2-7. The variability in costs for practices can be accounted for primarily through differences in site-specific applications and costs, differences in the reporting units used, and differences in the interpretation of reporting units.
[ Table 2-3 ] [ Table 2-4 ] [ Table 2-5 ] [Table 2-6 ] [Table 2-7 ]
The cost estimates for control of erosion and sediment transport from agricultural lands in Table 2-8 are based on experiences in the Chesapeake Bay Program, but are illustrative of the costs that could be incurred in coastal areas across the Nation. It is important to note that for some practices, such as conservation tillage, the net costs often approach zero and in some cases can be negative because of the savings in labor and energy.
The annual cost of operation and maintenance is estimated to range from zero to 10 percent of the investment cost (USDA-SCS-Michigan, 1988).