3.5  Cape Fear River Subbasin 03-06-18
Includes the South River and Big Creek
Municipalities: Cities of Dunn and Roseboro

 
LCFRP Station Codes (DWQ #):  SR (62)
DWQ/UNCW ambient monitoring site(s):  none
Waterbody:  South River
Location:  Harnett, Cumberland, Bladen and Sampson Counties.
 South River upstream of confluence with the Black River
Lat/Lon:  N    35.15600   W  78.64013  (SR)
               

Use Support Ratings, from NCDENR, DWQ (Cape Fear River Basinwide Water Quality Plan, July 2000): 
Freshwater Streams
Fully Supporting:                   165.9 mi.
Partially Supporting:             0.0 mi.
Not Supporting:                     0.0 mi.
Not Rated:                              113.7 mi.

        This subbasin is located on the inner coastal plain and includes South River and Black River (Little Black River), both major tributaries of the Cape Fear River.  Land use is primarily agriculture in the form of animal operations (mostly hog farms).  Most streams are slow moving black-water swamp streams.  There are three permitted dischargers within this subbasin.  (NCDENR, DWQ Cape Fear River Basinwide Water Quality Plan, July 2000)

        The South River (7.2 miles from source to NC 13) and the Little Black River (from Dunn to I-95) were both rated as partially supporting (PS) in the 1996 plan.  Neither river was sampled by DWQ because of low flow conditions, each is currently not rated (NR).  Both remain on the state’s year 2000 303(d) list.  Portions of the South River are not impaired; however, because of fish consumption advisories, this 70.9-mile segment is on the 303(d) list.  (NCDENR, DWQ Cape Fear River Basinwide Water Quality Plan, July 2000)

        All the waters of the subbasin are affected by nonpoint sources.  The Nature Conservancy has acquired a 295-acre tract in the Black River Watershed Outstanding Resource Waters (ORW) to demonstrate how the riparian buffer protects the river from nonpoint source pollution.  (NCDENR, DWQ Cape Fear River Basinwide Water Quality Plan, July 2000)

UNC-Wilmington – Center for Marine Science, LCFRP
Station Names:  SR
Data collection:  since February 1996
Sampling relevance:  Below City of Dunn, hog operations in watershed  

    
                          SR - below the Mingo Swamp

        This site was found to be non supporting (NS) by UNCW for dissolved oxygen; the North Carolina State Standard of 5.0 mg/L was not met 50% of the time, and the swamp standard of 4.0 mg/L was not met 42% of the time.  The lowest levels were found in summer months, with July of 2001 having dissolved oxygen concentration of 2.0 mg/L (Figure 3.5.1).  The mean for this site during the 2001-2002 period was 5.7 mg/L.

        This site was found to be fully supporting (FS) for chlorophyll a concentrations, only exceeding the North Carolina State Standard of 40 mg/L once, in June 2002 with concentrations of 65.3 mg/L.  Most other months the concentrations were very low, with a mean value of 7.0 mg/L.

        This site was partially supporting (PS) for fecal coliform bacteria concentrations, exceeding the North Carolina State Standard of 200 CFU/100 mL in 25% of all samples.  The highest concentrations were found in the winter months of December, January and February with concentrations of 240, 370, and 478 CFU/100 mL, respectively. 

        This site was found to be fully supporting (FS) for turbidity, with concentrations not exceeding 5 NTU.  The North Carolina State Standard for turbidity is 50 NTU.  This site had a mean value of 2 NTU.  

Figure 3.5.1  Dissolved oxygen concentrations (mg/L) for South River (SR).  The line shows
NC State Standard for dissolved oxygen of 5.0 mg/L and the dashed line shows NC State 
Standard for swampwater of 4.0 mg/L.