On Friday June 16, 2017 the Indiana Department of Environmental Management (IDEM) issued an Order to Columbus City Utilities requiring the Utility to issue a Boil Water Notice. IDEM communicated its order at 3:00 p.m. on Friday, June 16, and notices were immediately sent out to the news media, public health and safety agencies, each of which was duly notified by 4:30 p.m. on Friday, June 16.
Columbus City Utilities conducts routine water testing (40) times per month at eight (8) different locations throughout the water distribution system.
Routine samples were collected on Wednesday, June 14, 2017. The water samples were taken to the laboratory where the testing was conducted. There is a twenty-four (24) hour period before the results of the all tests are known.
On Thursday, June 15, 2017, one (1) of the samples was identified as positive for E-coli. Protocol requires that the Utility notify IDEM within 24 hours of a positive sample, which was done, and additional samples were collected from the same sampling location that originally tested positive, as well as locations upstream and downstream of that location. The test results of this second round of sampling were all negative for E-coli bacteria.
Bacteriological sampling of water system is a delicate process and is prone to false positives. Historically, Columbus’ routine water testing results in three (3) false positives per year for various surface contaminants, including E-coli bacteria. For this reason EPA and IDEM regulations do not call for public notification until the results are verified. In this case, the repeat tests proved the original test was erroneous.
In addition to the second round of sampling on Thursday, June 15, City Utilities took additional samples at all of the City’s (15) production wells.
The results of the second round of water sampling received on Friday, June 16th, proved no-contaminants within the distribution system; however, production well sampling resulted in Well #3-II testing positive for E-coli. That well was immediately shut down as of 3:00 p.m. on Friday, June 16th. Samples taken from all wells are taken directly from the well and prior to the water being treated by the water filtration system.
Due to the contaminants found in Well #3-II, the Indiana Department of Environmental Management directed the issuance of a Boil Water Notice.
Test results received on Saturday, June 17, confirmed that Well #3-II was contaminated with E. coli. In that sufficient time had elapsed since Well #3-II was taken off line for any contaminated water to have been removed from the system, IDEM allowed the boil order to be lifted at 3:00 PM on Saturday, June 17.
A follow up meeting was held on Monday, June 19, 2017 with representatives from Columbus City Utilities and the Indiana Department of Environmental Management. Well 3-II will remain off-line until any and all corrective measures have been completed and the well is ruled safe by the City and IDEM officials. City officials were able to successfully document to IDEM’s satisfaction that the disinfection process used at the water treatment plant is sufficient to kill any E. coli contamination that might have been within the raw water supply.
A full range (8) of water distribution samples were collected on June 19, 2017, and those results were all negative for any contamination.
The water is safe and there was never a risk to public health or safety.
Columbus City Utilities is committed to providing the highest quality and safest quality of drinking water and works closely with its regulatory agency, the Indiana Department of Environmental Management.
Additional information may be found at:
Indiana Department of Environmental Management:
www.in.gov/idem/cleanwater/2494.htm (Total Coliform Rule)
www.in.gov/idem/cleanwater/2450.htm (Ground Water Rule)