Section 319
NONPOINT SOURCE PROGRAM SUCCESS STORY
Stabilizing Streambanks and Restoring Wetlands Improves Habitat
Waterbody Improved
Streambank modification/destabilization contributed to total
suspended solids (TSS) impairment of a 6.6-mile segment of
Addison Creek in Illinois. Implementing streambank stabilization techniques and wetland
restoration measures through section 319 of the Clean Water Act (CWA) enhanced water
quality and helped Addison Creek meet TSS water quality goals for its designated water use
classifications.
Problem
Data collected in 1998 revealed that Addison
Creek was not supporting designated uses for
aquatic life, in part because of TSS. This data
also suggested that stormwater runoff contrib-
uted to the impairment through streambank
modification/destabilization. As a result, the
Illinois Environmental Protection Agency (EPA)
placed a 6.6-mile segment of Addison Creek in
Cook County, Illinois, on the 2002 CWA section
303(d) list of impaired waters (Figure 1).
Project Highlights
Illinois EPA used CWA section 319 funds to
implement three nonpoint source pollution
control projects in the Addison Creek watershed
since 1998. These projects reduced nonpoint
source pollution by applying bioengineering
techniques to stabilize approximately 8,720 feet
of eroding Streambanks. Specific techniques
included A-jacks with vegetation, Stabilator toe
with vegetation, riprap, lunkers, and vegetated
gabion baskets (Figures 2 and 3). The project
partners also removed selected trees to allow
increased light penetration, built riffles, and
planted native forbs, grasses, and sedges. In
addition, they restored a 30-foot-wide, 1.29-acre
wetland on each side of a 1,300-foot-long sec-
tion of stream (Figure 4).
Addison Creek is a tributary of Salt Creek, which
is also included on Illinois' CWA section 303(d)
list. A report containing the total maximum
daily loads and the implementation plan for
Figure 1. Map of
Addison Creek
watershed.
Figure 2. A gabion toe (cage filled with earth and rocks) protects
the left and right banks in this section of Addison Creek.
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Salt Creek was completed and approved in
September 2004.
Figure 3. Streambank stabilization techniques used on this portion
of the creek include vegetated banks with an A-Jacks toe on the left
bank and a Stabilator toe on the right bank.
Figure 4. Along this section of the creek, the partners restored a
streamside wetland and stabilized the Streambank with vegetation,
riprap, and riffles.
Results
Although Addison Creek was still identified as
not supporting designated uses for aquatic
life in 2006, TSS and Streambank modification/
destabilization have been removed as a cause
and source of impairment. TSS did not exceed
116 milligrams per liter in any samples from the
Ambient Water Quality Monitoring Network
station on Addison Creek between 2000 and
2003. Habitat data collected in 2001 at this sta-
tion rated bank vegetative protection/stability as
good. The segment will remain listed for excess
nutrients, various metals, pathogens, total dis-
solved solids, and flow regime alterations.
Partners and Funding
A combination of $444,561 in section 319
grants and $300,891 in matched costs
enabled Addison Creek Conservancy District
to implement Streambank stabilization prac-
tices. The restoration of the riparian buffer
zone was completed by the City of Northlake
using $296,443 in section 319 funding and
$2,000,000 local cost-share. The total cost of
this project was $3,041,895.
I
3J
U.S. Environmental Protection Agency
Office of Water
S Washington, DC
' EPA841-F-07-001GG
December 2007
For additional information contact:
Scott Ristau
Illinois Environmental Protection Agency
217-782-3362
Scott.Ristau@illinois.gov
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