title: Multiple modes of water quality impairment by fecal contamination in a rapidly developing coastal area: southwest Brunswick County, North Carolina.
abstract: Fecal contamination of surface waters is a significant problem, particularly in rapidly developing coastal watersheds. Data from a water quality monitoring program in southwest Brunswick County, North Carolina, gathered in support of a regional wastewater and stormwater management program were used to examine likely modes and sources of fecal contamination. Sampling was conducted at 42 locations at 3-4-week intervals between 1996 and 2003, including streams, ponds, and estuarine waters in a variety of land use settings. Expected fecal sources included human wastewater systems (on-site and central), stormwater runoff, and direct deposition by animals. Fecal coliform levels were positively associated with rainfall measures, but frequent high fecal coliform concentrations at times of no rain indicated other modes of contamination as well. Fecal coliform levels were also positively associated with silicate levels, a groundwater source signal, indicating that flux of fecal-contaminated groundwater was a mode of contamination, potentially elevating FC levels in impacted waters independent of stormwater runoff. Fecal contamination by failing septic or sewer systems at many locations was significant and in addition to effects of stormwater runoff. Rainfall was also linked to fecal contamination by central sewage treatment system failures. These results highlight the importance of considering multiple modes of water pollution and different ways in which human activities cause water quality degradation. Management of water quality in coastal regions must therefore recognize diverse drivers of fecal contamination to surface waters.
authors.affiliation: Department of Biology and Marine Biology, UNC Wilmington, Wilmington, NC, 28403, USA. Cahoon@uncw.edu.
authors.forename: Lawrence B
authors.initials: LB
authors.lastname: Cahoon
authors.affiliation: SEPI Engineering, 330 Shipyard Blvd., Suite 203, Wilmington, NC, 28412, USA. jhales@sepiengineering.com.
authors.forename: Jason C
authors.initials: JC
authors.lastname: Hales
authors.affiliation: Stormwater Engineering Group, Biological and Agricultural Engineering, North Carolina State University, Raleigh, NC, 27695, USA. escarey@ncsu.edu.
authors.forename: Erin S
authors.initials: ES
authors.lastname: Carey
authors.affiliation: National Oceanography Centre, Southampton, University of Southampton Waterfront Campus, European Way, Southampton, SO14 3ZH, UK. s.loucaides@noc.soton.ac.uk.
authors.forename: Socratis
authors.initials: S
authors.lastname: Loucaides
authors.affiliation: N. C. Division of Water Resources, N.C. Department of Environmental Quality, 127 Cardinal Drive Ext., Wilmington, NC, 28403, USA. kevin.rowland@ncdenr.gov.
authors.forename: Kevin R
authors.initials: KR
authors.lastname: Rowland
authors.affiliation: North Carolina Coastal Reserve and National Estuarine Research Reserve, Center for Marine Science, UNC Wilmington, 5600 Marvin Moss Lane, Wilmington, NC, 38409, USA. toothmanb@uncw.edu.
authors.forename: Byron R
authors.initials: BR
authors.lastname: Toothman
mesh_terms: D000818:Animals; D004784:Environmental Monitoring; D005243:Feces; D006801:Humans; D009657:North Carolina; D061005:Ponds; D011891:Rain; D045483:Rivers; D012722:Sewage; D014507:Urbanization; D014867:Water; D014871:Water Microbiology; D014876:Water Pollution / Q000032:analysis* / Q000706:statistics & numerical data; D060753:Water Quality / Q000592:standards
chemical_list: D012722:Sewage; D014867:Water
keywords: Fecal coliform bacteria; Groundwater; Septic tanks; Sewage; Silicate; Stormwater