Environmental Heath Laboratory

Drinking (Potable) Water Testing

The Environmental Health Laboratory is committed to protecting the public's health from waterborne illnesses by providing bacteriological testing services to our community. Our laboratory is certified by the North Carolina Department of Health and Human Services State Laboratory of Public Health for the analysis of total coliform/E.coli and Heterotrophic Bacteria. 

Testing services are available for compliance with regulatory agencies as well as noncompliance purposes. Public water systems, contractors, realtors, private well owners, or anyone needing bacteriological testing are encouraged to use our testing services. Sampling kits (bottles and forms) may be obtained at the Environmental Health office.

Methods of Testing

Drinking water samples are accepted between 8 a.m. and 4:30 p.m., Monday through Thursday except on holidays and the day before a holiday. The following methods of testing are used in the laboratory:

  • Colitag 16 – 48 hour EPA approved method is used for total coliform/E.coli analysis. Lab results can be obtained as early as 16 hours from start time of analysis. Results are reported qualitatively as "Present" or "Absent". This method can detect coliforms as few as 1 colony-forming unit (cfu)/ 100 milliliters of sample
  • SimPlate 45 – 72 hour EPA approved method is used for Heterotrophic Bacteria analysis. Lab results can be obtained as early as 45 hours from start time of analysis. Results are reported quantitatively as Most Probable Number (MPN)/mL. This method can detect Heterotrophic Bacteria as few as 1 MPN/mL of sample

Wastewater/Surface Water Testing

Fecal coliform, Enterococcus, and pH testing services are available for wastewater and surface water type samples. All testing methods used are EPA approved, however, lab results are for informational purpose only.

Lab results for these tests cannot be used for regulatory reporting. The following tests can be done in the lab:

  • E. coli - Colilert 18. Lab results can be obtained as early as 18 hours from start time of analysis. Results are reported quantitatively as MPN/100 mL. This method can detect E. coli bacteria as few as 1 MPN/mL in samples.
  • Enterococcus - ASTM Method D 6503-99 Enterolert. Lab results can be obtained as early as 24 hours from start time of analysis. Results are reported quantitatively as MPN/100 mL. This method can detect Enterococci bacteria as few as 1 MPN/mL of sample.
  • Fecal Coliform - Colilert 18. Lab results can be obtained as early as 18  hours from start time of analysis. Results are reported quantitatively as MPN/100 mL. This method can detect fecal coliform bacteria as few as 1 MPN/mL of sample.
  • pH – Standard Methods 4500 H B