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Urban Retrofit Leads to Reopening of Shellfish Harvesting Waters in
Battery Creek
U/afprhnHv lmnrn\/prl T^e Batterv Creek watershed in Beaufort County contains
considerable shellfish growing habitat, much of which has been
restricted for harvesting for over a decade due to fecal coliform contamination from stormwater
runoff. The City of Beaufort completed the Battery Creek Watershed Management Plan in 2013
and began a subsequent recreational pond rehabilitation and retrofit project in 2014. The project
was completed in 2017 and has contributed to water quality improvements that prompted the
reopening of these waters for the upcoming shellfish harvesting season beginning October 1, 2020.
Problem
The 9,874-acre Battery Creek watershed (hydrologic
unit code 030502080501) includes portions of the city
of Beaufort, Beaufort County and town of Port Royal.
The creek is a tidal estuary that ultimately connects
with the Beaufort River and Port Royal Sound along
the southeastern South Carolina coast (Figure 1).
Battery Creek's classified use is shellfish harvesting
(SFH), which has been restricted for over a decade
due to elevated fecal coliform levels. The project area
contains substantial urban and impervious surface
area (including a major highway intersection) that
receives no freshwater inputs other than those from
stormwater runoff from the developed watershed sur-
rounding it. Land uses include commercial, residential,
transportation and forest, which have the potential to
produce significant amounts of fecal coliform-laden
stormwater inputs to the waterway.
The South Carolina Department of Health and
Environmental Control (SCDHEC) Sheiifish Program
conducts monthly water quality monitoring at shellfish
stations 15-28, 15-27, 15-26, 15-25, 15-21 and 15-10
in Battery Creek. South Carolina's fecal coliform
standard for shellfish harvesting water states that the
90th percentile of available samples must be below
43 most probable number (MPN) per 100 milliliters
(mi_). These six sheiifish stations, located downstream
of the project site, have not reliably met standards for
shellfish harvesting based on annual shellfish sanitary
surveys. This has resulted in iong-term closures for
much of Battery Creek.
Battery Creek Watershed Sheljfish Stations Reopened
Beaufort S.C.
Burton Hill Retrofit BMP Site
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15-21


15-25
15-10
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Port Royal S.C.
Figure 1. Battery Creek supports shellfish habitat in
southeastern South Carolina.
Story Highlights
In 2014, Beaufort County and the City of Beaufort
partnered on the Burton Hill M2 Regional Water
Quality Retrofit project, which included the repair
and improvement of an existing private recreational
pond that was recognized as a good catch basin for
stormwater runoff. The project involved collecting
runoff from a 470-acre sub-basin of Battery Creek and
diverting the flow toward the pond. Here, attenuation

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Figure 2. The stormwater pond includes an outlet drain and an
emergency overflow structure.
Table 1. Data (90th percentiles) show that fecal
coliform levels have declined over time and are now
meeting1 the water quality standard.
Monitoring Station #
2019
2018
2017
2016
15-21
17
24
26
35
15-25
39
76
105
111
15-26
24
46
55
67
15-27
25
60
60
63
15-28
21
37
41
45
15-10
33
30
36
17
1Green values are meeting the standard of 43 MPN/100 mL
of the stormwater now allows ultraviolet light
to kill off bacteria and for sediment-delivered
bacteria to settle out of the water column
(Figure 2).
The preliminary estimate of fecal coliform load
reductions for this project, in combination with
other proposed best management practice
(BMP) retrofits in the Battery Creek Watershed
Management Plan, was 12 percent. Additionally,
there was an expected freshwater reduction of
approximately 4 percent. Shortly after construc-
tion, the area experienced a significant and
intense rainfail event with more than 4 Inches
of rainfali within the watershed over a 36-hour
period during an extremely high tide cycle. The
pond was evaluated during and after the storm
event, and was found to perform as designed,
with no water overtopping the banks. The proj-
ect was promoted to the public and stormwater
personnel through subsequent professional
workshops and media covered events.
Results
All shellfish monitoring sites in Battery Creek continued
to be monitored monthly after project completion,
and data showed that fecal coliform concentrations
have improved in most areas of the creek. At the six
formerly restricted stations, fecal coliform standards
have been achieved, resulting in the reclassification
from restricted to approved for shellfish harvesting
(Table 1). This will allow shellfish harvesting to occur in
these 948 acres of estuarine waters beginning October
1, 2020.
Partners and Funding
The successful reduction and treatment of stormwater
runoff was achieved by collaboration between U.S.
Environmental Protection Agency (EPA), SCDHEC, The
City of Beaufort, Beaufort County, and a local property
owner. The City and County agreed to partner on the
design, permitting and construction of the Burton
Hill M2 Regional Water Quality Retrofit project. EPA
and SCDHEC approved funding of $350,000 from an
EPA Clean Water Act section 319 grant. The City of
Beaufort and Beaufort County provided an additional
$285,686 funded through a stormwater utility fee.
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U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA 841-F-20-0Q1U
October 2020
For additional information contact:
Shea McCarthy
South Carolina Department of Health and
Environmental Control, Bureau of Water
803-898-4401 • mccartsm@dhec.sc.gov

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