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Illinois
Chain O'Lakes and Fox River Selected for Streambank Protection Project
The Chain O'Lakes and Fox River is an Illinois river system with an
on-stream lake in western Lake County and eastern McHenry County that provides
recreational opportunities for more than a million visitors each year. This
beneficial use is, however, potentially threatened by nonpoint sources in the
watershed. The lake and river are affected by runoff, shoreline and bank
erosion, and land disturbances (development). In addition, heavy boat traffic
on the lake often stirs up the bottom sediments, resuspending them in the
waterway.
To counter these problems, watershed partners began a bank protection
demonstration project. That is, using 319 funding, they implemented various
bank protection methods, thereby modeling a wide variety of management tools.
Among the many tools available, the project emphasized natural or vegetative
solutions, nonstructural management solutions, and other methods to hold the
soil.
Biotechnical methods
To demonstrate biotechnical protection methods, the project put advanced
erosion control materials and riparian vegetation at the base of the eroding
shoreline, where scour from wave action usually occurs. Special fabrics,
natural fiber products, wave breaks, or several of these in combination protect
root systems and trap sand, silt, and gravel along the water's edge. The result
is an aesthetically pleasing natural landscape that routine maintenance will
protect and improve. Leaving a buffer strip of plants at least 10 feet long and
mowed no lower than 6 inches is simple, inexpensive, and protective.
The benefits of biotechnical methods are many; they are cost-effective,
improve boating conditions (wave energy from boats and wind is absorbed, not
reflected), offer attractive and improved shoreline habitat, and yield better
water quality. While native plants are recommended, other plants can be used.
Species selected for revegetation projects should be adaptable to a moist
shoreline setting and local soil conditions. Common choices include red osier
dogwood, prairie cord grass, blue flag iris, and arrowhead. Biotechnical
methods prevent shoreline erosion, which in turn prevents sediments from
entering the water. Their use in this project led to the following overall
improvements:
- erosion prevention control,
- shoreline stabilization, and
- habitat restoration.
Created wetlands
The Chain O'Lakes and Fox River project also made the first inland use of a
"geotube" to create new wetlands along the Fox River. This fabric tube 30 feet
in circumference and 140 feet long is a piece of woven polyester that can be
filled with dredged sediment. Geotubes should last at least 15 years under
normal weather conditions, and they also act as a buffer against waves.
"It has worked amazingly well," said Karen Kabbes, the former executive
director of the Fox Waterway Agency. The agency hopes to use a series of
geotubes, linked together in a giant circle, for long-term protection. Wetland
plants are added once the interior is filled with sediment.
Nonstructural methods
Nonstructural management techniques include the creation of no-wake zones and
no- motor areas. The redirection of traffic routes to deeper locations, strict
dredging rules, monitoring and educational efforts (with some especially
directed to boaters) are other proposed management methods.
CONTACT: Laura Rinbenberger
Chain O'Lakes Fox River Waterway Management Agency
(708) 587-8540 |
Creating Useful Beauty -
The Skokie River Restoration Project
A brochure for the Chicago Botanic Garden invites people to "experience the
beauty that extends beyond floral color." This beauty now extends to the banks
of the Skokie River which flows through this 300-acre living museum. The
Chicago Botanic Garden has recently completed a restoration project on the
Skokie River with section 319 funding. The project was a partnership: the
Chicago Botanic Garden, Illinois Environmental Protection Agency, Northeastern
Illinois Planning Commission, and Applied Ecological Services shared
responsibilities and resources to save the river. In all, approximately 100,000
plants of various native species were planted along the river's edge.
A troubled past
The Skokie River, a 23-mile-long tributary of the North Branch of the Chicago
River, flows along Lake Michigan in Lake and Cook counties in northeastern
Illinois. The river is much altered from its presettlement conditions. Original
land maps from the area indicate that it was once a wet prairie, about
one-quarter-mile wide. Today, it is a channel not more than 20 to 40 feet wide.
The river was channelized in 1957, and over the last 30 years, its banks
have severely eroded. The Skokie also encounters pollution as it flows along a
major expressway: siltation, organic enrichment, nutrients, urban runoff,
hydrologic modifications, and habitat alterations are serious problems.
Erosion has exposed many underground pipes, and the river is often green
with mats of algae. Sedimentation downstream has created wide, shallow channels
with poor habitat and degraded buffer zones that also provide poor pollution
filtering capabilities.
Project toolbox
The Skokie River Restoration Project began during the summer of 1994 in
response to these degraded conditions. The project's goals are to stabilize
eroding streambanks, improve water quality, and enhance the streamside buffer
zones. It also serves as an educational tool. Workshops sponsored during the
project provide information about effective and economical restoration and
management techniques. Landscape professionals, urban and environmental
planners, conservation groups, and engineers are using information provided by
the project.
The project has used seven basic tools to help restore the river:
- Streambank planting. Native prairie grasses that have deep, dense
roots were planted to protect the river against erosion.
- Brush layering. Horizontal layers of willow and dogwood branches
were placed along the bank to hold the soil in place and reduce the energy of
the water against the bank.
- Willow posts. Dormant willow posts, which root profusely, were
pounded into the ground as a bank stabilization technique.
- Coir fiber rolls. Biodegradable coconut fiber rolls planted with
native wetland plants and placed along banks or in-stream further stabilize and
enhance aquatic habitats.
- Riffle enhancement. Placing large rocks and boulders in existing
riffles improved water aeration and habitat.
- No-till drill seeding. Approximately 11 acres of streamside buffer
were planted with native prairie plants.
- Wetland creation. A five-acre wetland was created on the river to
treat runoff. Approximately 48 species of native wetland plants will grow in
this system.
Information and education are integral components of the Skokie River
Restoration Project. The partnership developed a fact sheet that explains the
multifaceted project and streambank stabilization techniques and a 30-minute
video that documents the project's progress and describes its techniques,
methods, and materials. Students have even used the site to learn water
monitoring methods.
The Skokie River Restoration Project will remain an invaluable model of
inexpensive, vegetative solutions to impaired aquatic habitat and water
quality. Using native vegetation to stabilize and buffer the riverbanks
requires little maintenance and improves pollutant filtering and aquatic
habitat.
CONTACTS: Cynthia Baker
Chicago Botanical Garden
(847) 835-8300
Scott Ristau
Illinois Environmental Protection Agency
(217) 782-3362
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