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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.
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