CPF Chapter B-17

Section B: Chapter 17 – Cape Fear River Subbasin 03-06-17 209
Chapter 17 -
Cape Fear River Subbasin 03-06-17
Includes Town Creek, Smith Creek and the Brunswick River
17.1 Water Quality Overview
This subbasin is located in the outer Coastal Plain and in
estuarine regions of the basin. The subbasin contains the
City of Wilmington and the Town of Southport. Most
tributaries in this subbasin are backwater and slow moving
or tidal. A map of the subbasin, including water quality
sampling locations, is presented in Figure B-17.
Biological ratings for these sample locations are presented
in Table B-17. The current sampling resulted in impaired
ratings for one stream and 7,211 acres of impaired
estuarine waters in this subbasin. A summary of use
support ratings for estuarine waters is presented in Table
A-32. Refer to Appendix III for a complete listing of
monitored waters and use support ratings. See Section A,
Chapter 3, Table A-31 for a summary of lakes and
reservoirs use support data.
Forest and agriculture are the primary land uses; however,
Wilmington and surrounding suburban areas also
contribute to nonpoint source pollution. There are 49
permitted dischargers in the subbasin; half of which
discharge directly into the Cape Fear River. Ten of these
are major dischargers (>1 MGD), with the largest
dischargers being International Paper, Wilmington North
Side WWTP and Wilmington South Side WWTP.
Benthic macroinvertebrate data indicated improved water
quality at sites most affected by nonpoint sources during
this low flow year. Excellent (using draft criteria)
conditions were recorded from the Cape Fear River above
International Paper. The Cape Fear River below the
Federal Paper discharge showed no change in water
quality since the last sampling. A Good-Fair rating was
assigned to Livingston Creek, up from Fair in 1993. In
the estuarine area, water quality has remained stable at
Cape Fear River at Snows Marsh with only Moderate
impacts.
Subbasin 03-06-17 at a Glance
Land and Water Area (sq. mi.)
Total area: 547
Land area: 498
Water area: 49
Population Statistics
1990 Est. Pop.: 56,467 people
Pop. Density: 113 persons/mi
2
Land Cover (%)
Forest/Wetland: 74.7
Surface Water: 9.3
Urban: 4.1
Cultivated Crop: 7.6
Pasture/
Managed Herbaceous: 4.3
Use Support Ratings
Freshwater Streams:
Fully Supporting: 251.5 mi.
Partially Supporting: 3.8 mi.
Not Supporting: 0.0 mi.
Not Rated: 65.5 mi.
Estuarine Waters:
Fully Supporting: 16,314 ac.
Partially Supporting: 7,211 ac.
Not Supporting: 0.0 ac.
Not Rated: 925 ac.
Lakes:
Greenfield Lake - Not Rated
Boiling Springs Lake -
Fully Supporting

Section B: Chapter 17 – Cape Fear River Subbasin 03-06-17 211
Table B-17 Biological Assessment Sites in Cape Fear River Subbasin 03-06-17
BENTHOS Bioclassification
Site # Stream County Location 1993 1998
B-1 Cape Fear River Columbus ab Federal Paper Good-Fair Excellent
B-2 Cape Fear River Columbus be Federal Paper Fair Fair
B-3 Livingston Creek Columbus US 74 Fair Good-Fair
B-5 Hood Creek Brunswick US 74/76 no sample Good
B-9 Barnards Creek Brunswick US 421 no sample Fair-Good
B-10 Town Creek Brunswick ab SR 1413 no sample Good-Fair
B-11 Lewis Swamp Brunswick SR 1410 no sample Good-Excellent
B-18 Cape Fear River Brunswick Snows Marsh Moderate Moderate
FISH TISSSUE No. Samples
Exceeding Criteria
Station Description Year
Sampled
Total
Samples
Metals Organics Comments
FT-1 Cape Fear River
at Riegelwood
1998 23 8 0 EPA mercury limit exceeded in 4
bowfin and 4 bass samples;
FDA/NC mercury limit exceeded
in 1 bass sample
FT-2 Livingston Creek
near Acme
1998 20 11 0 EPA mercury limit exceeded in 11
samples of bass, bowfin, pickerel;
FDA/NC mercury limit exceeded
in 3 samples of bass and bowfin
FT-3 Cape Fear River
below Riegelwood
1994 15 3 0 EPA and FDA/NC mercury limit
exceeded in 3 bowfin samples
The highest incidence of elevated mercury in fish tissue was in Livingston Creek. Over half of
the fish tested, including bass, bowfin and pickerel, had levels of mercury above EPA limits.
Samples from the Cape Fear River near Riegelwood found lower, but still significant levels of
mercury in bass and bowfin tissues.
For more detailed information on water quality in this subbasin, refer to Basinwide Assessment
Report – Cape Fear River Basin – June 1999, available from DWQ Environmental Sciences
Branch at [phone].
17.2 Impaired Waters
Portions of Livingston Creek, the Cape Fear River and estuarine areas were identified as
impaired in the 1996 Cape Fear River Basinwide Water Quality Plan. Portions of the Cape Fear
River and estuarine areas are currently rated as impaired according to recent DWQ monitoring.
Current status of each of these streams is discussed below. Prior recommendations, future
recommendations and projects aimed at improving water quality for these waters are also
discussed when applicable. 303(d) listed waters are summarized in Part 17.3 and waters with
other issues, recommendations or projects are discussed in Part 17.4.
Section B: Chapter 17 – Cape Fear River Subbasin 03-06-17 212
Livingston Creek
Current Status
Livingston Creek (22.2 miles from source to Cape Fear River) was partially supporting (PS) in
the upper segment and not supporting (NS) in the lower segment in the 1996 Cape Fear River
Basinwide Plan. This stream is currently fully supporting (FS). The bioclassification improved
from Fair to Good-Fair for 1993 to 1998. Livingston Creek is no longer on the 303(d) list.
DWQ will continue to monitor this stream to determine the extent of impacts from both point
and nonpoint sources.
Cape Fear River (near Neils Eddy Landing, International Paper)
Current Status
The Cape Fear River (near Neils Eddy Landing) was partially supporting (PS) in the 1996 plan.
The Cape Fear River (3.8 miles near Neils Eddy Landing) is currently partially supporting (PS)
according to recent DWQ monitoring because of an impaired biological community. The
International Paper Board discharge and nonpoint source pollution are possible causes of
impairment. This segment is on the state’s year 2000 303(d) list (not yet EPA approved).
2000 Recommendations
The 303(d) list approach will be to resample for biological and chemical data to attempt to
determine potential problem parameters. The International Paper discharge will also be
monitored to determine the extent of impacts to this segment and other segments of the Cape
Fear River in this subbasin. See Part 17.4 below for recommendations for the Cape Fear River
mainstem that include this impaired section and the rest of the mainstem in this subbasin.
The Cape Fear River Estuary
Current Status
The Cape Fear River Estuary (5000 acres) was partially supporting (PS) in the 1996 plan because
of low levels of dissolved oxygen (DO). This same area is currently partially supporting (PS)
and is on the state’s year 2000 303(d) list (not yet EPA approved). The cumulative impacts from
WWTP discharges in the subbasin as well as nonpoint source pollution are suspected to be
significant contributors to the impairment. Swamp water drainage may also be a source of low
DO waters feeding into the estuary. Possible sources of nonpoint source pollution include
marinas, canal systems and septic systems.
2000 Recommendations
See Part 17.4 below for recommendations for the Cape Fear River mainstem that include this
impaired section and the rest of the mainstem in this subbasin.
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Other Estuarine Waters in Subbasin 03-06-17
Current Status
There are 2,211 acres of impaired estuarine waters (Southport, Buzzard Bay, The Basin and the
Cape Fear River) in the subbasin according to recent DWQ and DEH Shellfish Sanitation Section
monitoring (not including 5,000 acres of Cape Fear River Estuary discussed above). These
waters have been closed to shellfishing by the Division of Marine Fisheries (DMF) based on
recommendations by Division of Environmental Health Shellfish Sanitation Section. DEH
regulations specify closure of growing areas when fecal coliform bacteria levels exceed 14
colonies per 100 ml of water. These waters are on the state’s year 2000 303(d) list (not yet EPA
approved). Recommendations for improving water quality in these waters are discussed below.
Refer to Table A-32 for overall use support ratings for estuarine areas and Figure A-16 for a map
of DEH shellfish growing areas.
2000 Recommendations
In the Cape Fear River basin, there are a variety of activities that contribute to the degradation
and impairment of shellfish waters. These include, but are not limited to, urban stormwater
runoff, failing septic tanks, channelized waters, draining wetlands and marinas. Management of
various land use activities is needed to decrease fecal coliform bacteria levels in shellfish
growing areas, thereby, decreasing the acreage closed to harvesting.
Refer to Section A, Chapter 4, Part 4.14 for further recommendations regarding shellfish growing
areas.
17.3 303(d) Listed Waters
There is one stream segment (3.8 stream miles) one lake and 7,211 acres of estuarine waters in
the subbasin that are impaired and on the state’s year 2000 303(d) list (not yet EPA approved).
The Cape Fear River and impaired estuarine areas are discussed above. For information on
303(d) listing requirements and approaches, refer to Appendix IV.
17.4 Other Issues, Recommendations and Projects
Approximately 45% of the waters in this subbasin are impaired by nonpoint source pollution.
All the waters of the subbasin are affected by nonpoint sources. DENR, other state agencies and
environmental groups have programs and initiatives underway to address water quality problems
associated with nonpoint sources. DWQ will notify local agencies of water quality concerns in
this subbasin and work with these various agencies to conduct further monitoring, as well as
assist agency personnel with locating sources of funding for water quality protection.
The Lower Cape Fear River Program
The Lower Cape Fear River Program maintains several sampling stations in this subbasin that
are used along with DWQ ambient data to make use support determinations in this subbasin.
Section B: Chapter 17 – Cape Fear River Subbasin 03-06-17 214
This data is also being used to support modeling in the Cape Fear River Estuary. Refer to
Section C, Part 1.4.5 for more information on the program and the UNCW Center for Marine
Sciences.
Mercury Advisories
DWQ sampling in 1994 and 1998 noted mercury in fish tissue at levels greater than EPA limits
and FDA/NC limits. Mercury in fish tissue is not exclusive to the Cape Fear River basin. In
recent years, elevated levels of mercury in some fish species have been noted in other coastal
areas. This issue is discussed further in Section A, Chapter 4, Part 4.8.4.
1999 Hurricanes
In September and October 1999, three hurricanes made landfall near the mouth of the Cape Fear
River. Although streams throughout the basin were impacted, the streams in the lower Cape Fear
River subbasins were severely impacted. The extent of water quality problems and recovery of
ecosystems in this subbasin will not be known for some time. See Section A, Chapter 4, Part
4.11 for information on Hurricane Fran in 1996.
Greenfield Lake
Greenfield Lake is owned by the City of Wilmington and was built before 1750. Originally a
cypress swamp, the lake was impounded to provide water for milling and irrigation for the
Greenfields Plantation that surrounded it. The city encompasses the lake and its watershed.
Greenfield Lake is currently swampy and cypress-filled. The City of Wilmington no longer
dredges the lake, but is treating the aquatic macrophytes with chemicals and grass carp. In the
summer of 1998, there was a fish kill in Greenfield Lake following a rainfall event. Significant
beds of submerged filamentous algae and floating mats of duckweed (Lemna sp.) and watermeal
(Wolffia sp.) were observed at nuisance levels in the lake in 1998. The filamentous algae in the
lake also appeared to be worse in 1998, as compared with previous years, while the clarity of the
water in the lake appeared to have improved in the past few years. Greenfield Lake is currently
not rated (NR) but is on the state’s year 2000 303(d) list (not yet EPA approved) because of
aquatic weeds and nutrient enrichment.
Cape Fear River from Lock and Dam #1 to the lower Cape Fear River Estuary
1996 Recommendations
Because of documented water quality problems related to low dissolved oxygen (DO) in the
Cape Fear River below Lock and Dam #1, all new and expanding discharges will be required to
complete an engineering alternatives and economic analysis. If no other alternatives are found to
be feasible, then a detailed evaluation of the potential impact of the discharge will be required
and recommended summer permitted limits will be as follows:
Section B: Chapter 17 – Cape Fear River Subbasin 03-06-17 215
New and expanding municipal/domestic discharges <1 MGD: BOD5 = 12 mg/l, NH3-N = 2 mg/l
New and expanding municipal/domestic discharges 1 MGD: BOD5 = 5 mg/l, NH3-N = 2mg/l
New industrial discharges: BOD5 = 5 mg/l, NH3-N = 2 mg/l
Expanding industrial discharges: best available technology or BOD5 = 5 mg/l, NH3-N = 2 mg/l
It was also recommended that Arcadian and Wilmington Northside WWTP change from Whole
Effluent Toxicity test procedure to 24-hour acute toxicity test at 90% effluent concentration.
These discharges are now using this toxicity test.
2000 Recommendations
The impaired segments are discussed above in Part 17.2. The 303(d) list approach will be to
develop a TMDL for this segment of the Cape Fear River because of low dissolved oxygen (DO)
levels. A TMDL is currently under development in cooperation with the Lower Cape Fear River
Program (Section C, Chapter 1, Part 1.4.5) and the interested stakeholders. Because of the nature
of the river/estuary system in this portion of the Cape Fear River basin, addressing water quality
issues must not be limited to problems detected in impaired segments alone. Until an EPA
approved TMDL to address low DO is in place to guide wasteload allocation decisions in this
portion of the Cape Fear River and Cape Fear River Estuary, recommended summer limits for
oxygen consuming wastes for new and expanding discharges will be as follows:
New and expanding municipal/domestic discharges <1 MGD: BOD5 = 5 mg/l, NH3-N = 2 mg/l
New and expanding municipal/domestic discharges 1 MGD: BOD5 = 5 mg/l, NH3-N = 1mg/l
New industrial discharges: BOD5 = 5 mg/l, NH3-N = 2 mg/l
Expanding industrial discharges: site specific best available technology or
BOD5 = 5 mg/l, NH3-N = 2 mg/l
Because this segment of the Cape Fear River and Cape Fear River Estuary is impaired and on the
state’s year 2000 303(d) list (not yet EPA approved), issuance of permits for new and expanding
discharges that would further increase the load of oxygen-consuming waste into these waters will
be carefully considered on a case by case basis.
For information on model development in this segment of the Cape Fear River estuary, see
Section A, Chapter 4, Part 4.6.
Coastal Urban and Recreation BMP Demonstration Project
This project will evaluate and implement BMPs to protect coastal waters impaired by
development. For more information on this project, refer to Section C, Chapter 1, Part 1.5.4.