United States
Environmental Protection
Agency
Office of Water (WH-556F),
Office of Wetlands, Oceans,
and Watersheds (A-104 F)
EPA843-F-93-001y
March 1993
WETLANDS FACT SHEET #25
Wetlands and Runoff
Since wetlands are typically the lowest
points on the landscape, they often receive runoff
from surrounding land. Runoff can be collected,
conveyed or discharged from conduits, pipes,
animal feedlots, waste treatment plants or float-
ing crafts. In addition, precipitation, atmospheric
deposition, seepage, or hydrologic modifications
can result in runoff that moves over and through
the ground picking up natural or anthropogenic
pollutants, which then become deposited directly
into surface or groundwater. In either case, as
runoff move across the land, water picks up and
carries with it pollutants which ultimately end up
in rivers, lakes, groundwater, and wetlands.
they art omtaminated or their :
ihdestuaries,
protected.
wetlands,
Should be
including
[•:PA PKOCRAMS
Clean Wafer Act §402(p)
Section 402(p) requires stormwater permits
for four major classes of stormwater dis-
charges: (1) a discharge with respect to
which a permit has been issued under Sec-
tion 402 before the date of the enactment of
this subsection, (2) a discharge associated
with industrial activity, (3) a discharge from
a municipal separate stormwater sewer
system serving an incorporated or unincor-
porated, urbanized population greater than
100,000, and (4) a discharge that contrib-
utes to a violation of a water quality stan-
dard or is a significant contributor of pol-
lutants to waters of the United States. This
program has issued guidance for prepara-
tion of permit applications for regulated
municipal and industrial stormwater dis-
charges. In addition, it stresses the use of
best management practices (BMPs) to mini-
mize or eliminate the contribution of pol-
lutants to stormwater discharges to waters
of the United States, including wetlands.
Clean Water Act §319
EPA supports a national program to con-
trol nonpoint sources of pollution. EPA
stresses a watershed based approach to
nonpoint source management which can
include protection or restoration of wet-
lands and riparian areas to reduce nonpoint
source pollution. EPA has funded a num-
ber of these projects under Section 319(h).
Coastal Zone Act Reauthorization
Amendments (CZARA) of 1990 §6217
EPA and the National Oceanic and Atmo-
spheric Administration have developed
guidance specifyingmanagementmeasures
for nonpoint source pollution affecting
coastal waters. Included in the guidance
(released January 1993) is a chapter on pro-
tection and restoration of wetlands and
riparian areas, and use of vegetated treat-
ment systems for nonpoint source control.
FOR MORE INFORMATION: call the EPA Wetlands Hotline* at 1-800-832-7828
•contractor operated
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IMPACTS TO WETDUNDS •
off resulted in mortality and deformities of wild-
life populations, particularly fish and migratory
birds.
Untreated runoff from agricultural land,
urban areas, and other sources is a leading cause
of water quality impairment. Siltation, excess
nutrients, changes to water flows such as, more
frequent inundation, and increased turbidity are
responsible for most of the impacts to wetlands
from runoff.
Impacts to wetlands have resulted in con-
sequences such as changed species composition,
increased pollutant loadings (e.g., heavy metals),
and replacing complex wetland systems with less
desired open water. Modifications of wetlands
associated with some stormwater management
practices have resulted in-significant impacts to
wetlands.
Some impacts have been particularly
tragic, such as in Kesterson and Stillwater Wild-
life Refuges, where untreated, contaminated run-
EPA is developing technical information
that landowners can use to protect the many func-
tions of wetlands, including water quality im-
provement. An issue paper highlighting the im-
pacts of stormwater on wetlands entitled, Natural
Wetlands and Urban Stormwater: Potential Impacts
and Management, is available through the EPA
Wetlands Hotline. A guide describing best man-
agement practices to pretreat stormwater runoff
before it enters a natural wetland is also being
developed. Additional materials on wetlands pro-
tection and restoration for nonpoint source ben-
efits will be developed to assist in implementation
of the wetlands and riparian areas chapter in the
CZARA Management Measures Guidance. EPA
will continue to work to address potential oppor-
tunities and conflicts regarding wetlands and pro-
grams addressing runoff.
ADDITIONAL INFORMATION;
• For additional information regarding the Section 319 program or the CZARA guidance,
contact the EPA Nonpoint Source Control Branch at (202) 260-7100.
• For additional information about the Section 402 stormwater program, contact the
Stormwater Hotline at (703) 821-4823.
FOR MORE INFORMATION: calUfie'EP A. Wetlands Hotline* at l-800-832r.7828.
'contractor operated
£& Printed on Recycled Paper
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