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{NONPOINTSOIREE SICEESS STORY
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Making Progress Through Implementation and Partnership in
Brunson Swamp
Waterbody inpTON/ed NonP°int source pollution from agriculture arid failing septic
systems contribute to elevated bacteria levels in Brunson Swamp.
The waterbody failed to attain its primary recreation designated use, prompting South Carolina
to add Brunson Swamp to the 2014 Clean Water Act (CWA) section 303(d) list for Escherichia
coli bacteria impairment. In response, stakeholders implemented agricultural best management
practices (BMPs), repaired failing septic tanks, and conducted outreach throughout the watershed.
Water quality in Brunson Swamp has significantly improved; however, it will remain listed as
impaired until bacteria levels consistently meet water quality standards.
Problem
Brunson Swamp is a blackwater system in the Lower
Coastal Plain that drains to the Little Pee Dee P^ver in
the greater Pee Dee basin. The mostly rural Brunson
Swamp watershed is in Horry County south of the
town of Aynor (Figure 1). The watershed is 16,000
acres, with most of the land being forested (48 per-
cent) or devoted to agriculture (44 percent).
Brunson Swamp was included in a larger CWA sec-
tion 319 implementation effort with Chinners Swamp
and Palmetto Swamp, which all discharge to the Little
Pee Dee River. Before this implementation project,
water quality monitoring had not been conducted in
the Brunson Swamp watershed. Beginning in 2011, as
part of the implementation project, South Carolina
Department of Health and Environmental Control
(SCDHEC) began monitoring at station PD-370 to assess
whether bacteria levels supported recreational use.
Until 2013, state criteria for fecal coliform bacteria
in freshwaters required that at least four samples
collected over a 30-day period could not exceed a
geometric mean of 200 colony forming units (CFU)
per 100 milliliters (mL), with a single sample maximum
(SSM) of 400 CFU/lOOmL. After 2013, state criteria for
E. coli require that at least four samples collected over
a 30-day period cannot exceed a geometric mean of
126 most probable number (MPN) per 100 mL, with
a SSM of 349 MPN/100 mL In most cases, insufficient
data are collected to evaluate against the geometric
mean criterion of the water quality standard; there-
fore, evaluation against SSM criterion is necessary. The
Brunson Swamp Watershed
Broad
Catawba
Saluda
Savannah
PD-370
Edisto
Santee
Salkehatchte
1:2311,162
100 mi
Figure 1. The Brunson Swamp watershed (in orange) has
shown water quality progress at SCDHEC monitoring
station PD-370.
CWA section 303(d) impaired waters list assessment
methodology allows for no greater than 10 percent
exceedances of the SSM criteria during a five-year
assessment window. Upon review of data collected in
2011 and 2012, SCDHEC placed Brunson Swamp on the
CWA section 303(d) list of impaired waters in 2014 due
to exceedances of the recreational use SSM criterion.
Project Highlights
In 2011 the Horry Sol! and Water Conservation District
(Horry SWCD) began an effort to repair septic tanks
and implement agricultural BMPs as part of the Horry,
Aynor, and Dogbluff (HAD) Water Quality Project. As

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Figure 2. Farmers installed alternative watering tanks
in the Brunson Swamp watershed.
part of the project. Horry SWCD planned to repair 80
failing septic tanks. By the end of the project in 2015,
Horry SWCD worked with landowners to exceed this
goal, successfully repairing 120 failing systems.
A key component of this steady success was the face-
to-face work between conservation staff and landown-
ers. The main objectives of the agricultural component
included minimizing concentrated manure deposition
from livestock operations and educating landowners
about manure and pasture management. A compre-
hensive nutrient management plan was developed
for a participating swine producer, which included
calibrating a spreader and installing a pumping plant
to agitate manure. In 2013 the swine farmer hosted an
Animal Waste Field Day where Clemson Extension staff
spoke to 25 livestock producers.
Horry SWCD continued advertising using flyers posted
in local businesses, such as feed and tack stores, and
hand-delivered to local churches. The SWCD hosted
two workshops focused on soil conservation, forage
enhancement, and herd health throughout the project
area. The SWCD also worked with participating land-
owners to start rotational grazing with their livestock
(affecting 593 pasture acres) and worked with livestock
producers to exclude herds from waterways and
provide alternative water sources. In total, nine wells,
28 water storage tanks, and 9,450 feet of pipeline
were installed for livestock alternative water sources
(Figure 2), and 1,600 feet of fencing was also installed
to physically exclude 359 livestock from waterways.
Horry SWCD also had an extensive outreach pro-
gram that focused on the public and their impact on
water quality. Representatives had a water quality
Samples Exceeding Standards: E. Co//at
Station PD-370 [Brunson Swamp]
18%
2014
2016
2018
Figure 3. Percent exceedance of the E. coil single
sample maximum standard at Station PD-370.
information booth at Swampfest and Baby Animal Day
held at the Playcard Environmental Education Center.
These events were open to all Horry County residents
and were attended by approximately 2,000 people.
Results
Monitoring in the watershed began in 2011 with the
start of the project and continued during and after
implementation, in total, implementation efforts
reduced pollutant loadings of nitrogen by 8,704
pounds, phosphorous by 2,170 pounds, and sediment
by 114 tons. Monitoring from 2011 to 2018 shows
that monitoring site PD-370 steadily improved, as the
percent of samples with E. coli bacteria exceedances
decreased from 35 percent to 18 percent (Figure 3).
Although water quality standards have not yet been
met, continued implementation efforts and monitoring
in the watershed may continue to show incremental
improvements.
Partners and Funding
The HAD Water Quality Project was made possible by
the efforts of several organizations led by the Horry
SWCD. Horry SWCD encouraged participation using
partnerships with U.S. Department of Agriculture's
Natural Resources Conservation Service, Horry County,
Grand Strand Water and Sewer Authority, the town of
Aynor, and local landowners. These partners and land-
owners supported the project by providing $517,780
in cash and in-kind services for BMP cost-share. In
addition, funding sources included $525,115 in CWA
section 319 funding from SCDHEC.
U.S. Environmental Protection Agency
Office of Water
Washington, DC
W .1
^ EPA 841-F-18-001LL
pR0*t^° November 2018
For additional information contact:
Carmony Corley
South Carolina Department of Health and Environmental
Control, Bureau of Water
803-898-4401 • corleycl@dhec.sc.gov

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