Section 319
NQNPDINT SOURCE PROGRAM SUCCESS STDRY
Implementing Agricultural Best Management Practices Reduces Bacteria
and Turbidity Levels
Watprhnrlipc; Imnrnvprl Erosion due to grazing and other agricultural activities on poorly
I pi UVWU managed livestock pasture near Fourth Creek led to increases
in turbidity and fecal coliform levels in the stream. As a result, the North Carolina Division of Water
Quality (NC DWQ) added three segments of Fourth Creek to the state's 1998 Clean Water Act (CWA)
section 303(d) list of impaired waters. Local partners installed agricultural best management practices
(BMPs) including alternative watering facilities and pastureland management. Water quality improved,
prompting NC DWQ to remove the three segments from the state's 2010 CWA section 303(d) list for
various impairments, including fecal coliform and turbidity.
Problem
Fourth Creek (Figure 1) flows through Iredell and
Rowan counties in the western piedmont region of
North Carolina. Water quality monitoring showed
that three segments of Fourth Creek violated the
state's fecal coliform water quality standard, which
requires that fecal coliforms (1) not exceed a geomet-
ric mean of 200 colonies (col) per 100 milliliters (ml),
based on at least five consecutive samples examined
during any 30-day period, and (2) not exceed 400
col/100 ml in more than 20 percent of the samples
examined during that period. North Carolina identi-
fied the source of fecal coliform as livestock grazing
practices that allowed direct stream access.
Water quality monitoring data collected by the North
Carolina Department of Environment and Natural
Resources (NCDENR) also showed occasional
violations of the water quality standard for turbidity,
which requires that turbidity be below 50 nephelo-
metric turbidity units (NTUs). NCDENR identified soil
erosion on agricultural areas, particularly row crops
and livestock grazing areas, as the most common
source of turbidity in the Fourth Creek watershed.
On the basis of data showing violations of water
quality standards, the NC DWQ added a total of
23.8 miles of Fourth Creek to the state's 1998 CWA
section 303(d) list for fecal coliform (three segments)
and turbidity (two segments) impairments. In 2008
NC DWQ added two additional impairments—bio-
logical integrity and fish community—to some of
Fourth Creek's impaired waters listings. Table 1 lists
the segments and associated impairments included
on the state's 2008 list of impaired waters.
Figure 1. Fences
exclude livestock
from the riparian
area along Fourth
Creek.
Table 1. North Carolina's 2008 CWA section 303(d)
list of impaired waters for Fourth Creek (Note:
Listings are based on data from 2002-2006.)
Assessment
Units
12-108-20a1
12-108-20a2
12-108-20a3
DWQ
Sub-basin
03-07-06
03-07-06
03-07-06
Length
(miles)
10.2
5.8
7.8
Violation (Impairment)
biological integrity,
fecal coliform
fecal coliform,
turbidity
biological integrity,
fish community,
turbidity, fecal
coliform
NC DWQ completed total maximum daily load (TMDL)
studies on Fourth Creek for fecal coliform and turbidity.
The U.S. Environmental Protection Agency approved
the fecal coliform TMDL in 2001 and the turbidity TMDL
in 2004. The TMDLs identify poorly managed livestock
grazing areas and agricultural activities as the primary
sources of the creek's impairment and consequent loss
of biological integrity. Most notable in this study was the
widespread finding of stream bank erosion and habitat
degradation.
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Project Highlights
Project partners worked together to implement
BMPs to reduce the amount of sediment and
fecal coliform bacteria entering Fourth Creek. The
Carolina Land and Lakes Resource Conservation
and Development (RC&D) office used CWA sec-
tion 319 funds to implement BMPs that would help
achieve the goals outlined in the approved turbidity
and fecal coliform TMDLs. The project began in
July 2003 and continued through July 2006.
Landowners installed 18,328 feet of livestock
exclusion fencing, which reduced cattle's access
to stream banks and allowed riparian buffer areas
to become revegetated (see Figure 1). Landowners
planted 2.18 acres of critical area and installed one
stream crossing to limit stream access and allow
the rotation of pastureland grazing. In addition, land-
owners installed 18 watering facilities (Figure 2),
three manure pumping tanks, and one waste irriga-
tion reel system.
Figure 2. An
alternative
watering tank
offers livestock
a water source
away from the
creek.
Field days played a large role in public outreach,
conveying the importance of installing agricultural
BMPs and their positive effects on water quality.
Project partners held five field days at BMP demon-
stration sites throughout the Fourth Creek water-
shed. All the field days were open to the public,
public officials and the media.
Results
The BMPs implemented through this project have
improved water quality in Fourth Creek. As Table 2
shows, turbidity levels in two previously impaired
segments now meet the water quality standard for
turbidity (no more than 10 percent of samples may
exceed 50 NTU). On the basis of these data, NC
DWQ removed both the 5.8- and 7.8-mile segments
of Fourth Creek from the state's 2010 CWA section
303(d) list for turbidity.
Table 2. Percentage of samples that
exceeded the turbidity standard,
post-project
Assessment Units
12-108-20a2
12-108-20a3
Length (miles)
5.8
7.8
Percent Exceedance (%)
6.7
3.3
Implementing pasture grazing BMPs significantly
reduced the fecal coliform counts in Fourth Creek.
As Table 3 shows, fecal coliform levels in two seg-
ments now meet the fecal coliform standard (no
more than 20 percent of samples may exceed 400
col/100 ml). On the basis of these data, NC DWQ
removed both the 5.8- and 10.2-mile segments of
Fourth Creek from the 2010 CWA section 303(d) list
for fecal coliform.
Table 3. Percentage of samples that
exceeded the fecal coliform standard,
post-project
Assessment Units
12-108-20a1
12-108-20a2
Length (miles)
10.2
5.8
Percent Exceedance (%)
< 20
< 20
In summary, project efforts in the Fourth Creek
watershed resulted in the full restoration of the
5.8-mile segment (which has attained both fecal
coliform and turbidity standards) and partial restora-
tion of the 7.8- and 10.2-mile segments (which
have attained only the turbidity standard and fecal
coliform standard, respectively). The 10.2-mile and
7.8-mile segments remain on the 2010 CWA section
303(d) list because of biological integrity impair-
ments. The 7.8-mile segment also remains listed for
fecal coliform and fish community impairments.
The active partnerships in the area continue to
implement agricultural cost-share BMPs with the
objective of obtaining full restoration of these
remaining Fourth Creek segments and removing
them from the state's CWA section 303(d) list in the
future.
Partners and Funding
A total of $97,214 in CWA section 319 grant funds,
supplemented by an additional $133,000 in match-
ing funds, supported this project. Partners included
North Carolina Agricultural Cost Share Program,
Iredell and Rowan Soil and Water Conservation
Districts, and Carolina Land and Lakes RC&D, Inc.
UJ
O
U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-10-001CC
September 2010
For additional information contact:
Heather Jennings
North Carolina Division of Water Quality
Heather.B.Jennings@ncdenr.gov
919-807-6437
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