905R90118
United States
Environmental Protection
Agency
Watershed Management Unit
Water Division
Chicago, IL
December 1990
vvEPA
Integrated Stream Management
Programs Reduce Impacts to
Aquatic Habitat
roperly managed stream corridors that achieve a balance
between development, water quality, and stream uses can
reap a wealth of economic, social, and cultural benefits for
communities.
The Problem
s the economic advantages of
development and urbanization place
increasing demands on land use
within stream corridors, streams are
not managed comprehensively to
protect water quality and beneficial
stream uses. Stream management
typically has taken the form of floodplain
management, which places emphasis on the
protection of individuals and structures from flood
hazards. This type of stream management has
often neglected the protection and/or the
enhancement of aquatic habitat and water quality.
Physical Modifications
ypical physical modifications of
stream channels to improve
drainage and to reduce flooding of
developed areas include:
• straightening of sinuous
systems,
• concrete lining of channels
(Figures 1a&b),
• replacing open channels with
underground culverts,
• dredging existing channels (Figure 2),
• construction of dams and reservoirs, and
• removal of stream bank vegetation.
Development along stream channels also
results in the removal of natural buffer strips and
zones and the creation of access roads and
stream crossings that cause further physical
changes to the stream and impact aquatic habitat
(Figure 3).
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Figure 1a.—Concrete-lined channel (apron).
1 ! ' *i^%- -• "
Figure 1b.—Concrete-lined channel (apron).
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t f ^ft^1,**"
I Figure 2.—Dredging of channels.
Figure 3.—Riprap—stream crossings.
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Statewide Programs
he following are a few examples of
selected state programs whose
long-term goals are to protect water
quality and other uses of their
natural water resources through
nonpoint source programs that
utilize stream corridor management
tools.
State of Maryland -
Nonpoint Source Control Program,
Maryland Office of Environmental Programs,
Baltimore, Maryland
The State of Maryland has had a number of
nonpoint source control implementation programs
dating back to the late 1960's and early 1970's. In
1984, the Maryland General Assembly added new
programs and modified existing programs. As of
1985, the State of Maryland had 12 different
programs regulated at the State or local level as a
comprehensive approach to controlling nonpoint
source pollution derived from increased
development and physical modifications to critical
habitat. A brief description of some of these
programs is provided below.
• Sediment control legislation—No clearing,
grading, or transporting of soil can take place until
the developer submits an erosion and sediment
control plan to the local soil conservation district
for approval. To be granted a local grading or
building permit, the developer must specify that he
will carry out the plan.
• Stormwater control—The State's stormwater
management regulations represent a diversified
approach to controlling the hydrologic
consequences of urban development rather than
focusing on controlling peak flows. Consideration
is given to volume reduction, low flow
augmentation, water quality control, and ecological
protection.
• Shoreline erosion control—Provides for the
abatement of shoreline erosion by identifying
critically eroding areas and promoting structural
control (i.e., bulkheads and riprap). Less critically
eroding areas are stabilized through less
expensive vegetative means.
• Development of critical areas
commission—Through a State/local partnership,
the commission works to develop and adapt
protection plans for critical shoreline areas. The
ultimate goal is to foster more sensitive
development activities to minimize damage to
water quality, natural habitat, and scenic values.
• Retention of existing forest I and—Existing
forests around the Chesapeake Bay and its
tributaries are maintained to intercept surface
runoff and allow it to infiltrate the soil profile before
reaching the receiving water.
• Conservation easements—The State program
of acquiring conservation easements encourages
private landowners to preserve and protect
undeveloped or low density areas.
• Dredge and fill projects—The State water
quality certification program pursuant to sections
401 and 404 of the Clean Water Act was expanded
to review construction projects for which water
quality certificates are required.
• Nontidal wetlands program—The cooperative
State and county government program that
encourages and assists local governments with
the design and implementation of locally
administered nontidal wetlands management
programs.
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• using natural or constructed wetlands as
sediment, nutrient, and pollutant filters,
• managing regional detention basins for
multiple uses,
— Dry basins (playgrounds, soccer fields,
etc.)
— Wet basins (wetlands, living lakes,
aesthetics)
• providing stricter control on zoning changes,
and
• implementing construction and
development-related ordinances and laws.
These techniques and many others can be
integrated into a stream corridor management
program that combines land use planning,
engineering controls, and legislative controls.
Successful stream corridor
management tools include:
m A land use planning and problem solving
framework or approach,
• Local, statewide, and regional policies and
regulations for construction, maintenance,
erosion control, and zoning, etc.,
• Community education and
involvement in stream
conservation and protection
programs,
• Establishing Best
Management Practices
(BMPs) for minimizing
disturbances to streams
(i.e., stream crossing
BMPs, stream
channelization BMPs,
BMPs for dredging and
gravel removal),
• Land acquisition for protecting critical areas,
for acquiring recreational lands, or for public
access,
• Land use controls including zoning,
subdivision regulations, and other regulatory
techniques,
• Floodplain management and regulations,
• Tax incentives to riparian landowners to
protect and enhance stream corridors,
• Development of governmental aid programs,
• Development of special improvement districts,
• Enactment of watershed rules and
regulations to protect water supplies and
water quality, and
• Establishment of Wild, Scenic, and
Recreational Rivers programs.
When some or all of these tools are applied to
stream corridor management, natural and diverse
habitats are maintained and degradation of water
quality is prevented. The aesthetic, recreational,
and cultural values of the stream are maintained
and possibly enhanced, resulting in both
environmental and economic benefits to the
community (Figure 5).
Figure 5.—Undeveloped habitat—aesthetic and recreational values, and aquatic
habitats are preserved.
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The Impacts
he impacts of development and
subsequent stream channel
modifications on aquatic life and
habitat (Figure 4) include:
• physical destruction or
impairment of food, shelter,
spawning, and nursery habitat,
physical displacement of species,
impediments to fish migration,
loss or reduction in species diversity, and
changes in species composition.
c _
I —
DeKtrur.tion of
pools and baffles
Culling off of
meanders and
shortening of
stream length
Deepening of
channel
Removal of •
bank erosion
1
Widening of
the channel
Increased
downstream
flood hazard
Loss of
\to habitat
diversity
Increased Loss of
sediment >• potential
loads aquatic
\habilat
Decrease
_^*Jr in water
— .
^ 4 quality
^ /
/
/
Loss of food
_ i ;
w prou ui*iny
invertebrates.
W
0
o
"3
_2
o
CQ
Figure 4.—Effects of channelization on the physical environment and biota of streams (J.R. Karr and I.J. Schlosser, 1978).
The Solution - Integrated Stream Management
n integrated or comprehensive
stream management program is
essential to maintain the balance
between urban development,
maintenance of water quality, and the
protection of aquatic habitat within
urbanized watersheds. A
comprehensive corridor management
program places the primary emphasis on water
quality protection through the control of nonpoint
source pollution (i.e., erosion and sedimentation)
and on the protection of natural and cultural
resources within the stream corridor. As a result,
floodplain management becomes a part of the
integrated management of streams.
Comprehensive stream
management techniques include:
m identifying critical streams and habitat to
manage,
• managing land use along the entire length of
a stream both upstream and downstream of
the stream reach of interest,
• performing minimal channel re-shaping and
straightening,
• implementing bank stabilization measures,
• incorporating physical structures in the
channel design to improve habitat,
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TERRENE
INSTITUTE
For further information on Comprehensive Stream Management, contact the New York State
Department of Environmental Conservation, Division of Water, Bureau of Water Quality, Albany,
New York 12233, or see Stream Corridor Management: A Basic Reference Manual. New York
State Department of Environmental Conservation, Albany. 1986, second printing. This project was
funded by the U.S. Environmental Protection Agency Office of Water Enforcement and Permits-
Water Permits Division and managed by Region V Watershed Management Unit-Water Division.
Prepared by Dynamac Corporation, FTN Associates, and JT&A, Inc. For copies of this publica-
tion, contact The Terrene Institute, 1000 Connecticut Avenue, NW, Suite 300, Washington, DC
20036, (202) 833-3380.
7~X £\ Printed on Recycled Paper
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