Wednesday, Feb. 27, it was discovered the recently constructed wastewater treatment plant in Empire experienced high fecal coliform bacteria counts in the sample that was taken yesterday (the test takes 24 hours to yield results). Fecal Coliform are used as indicator organisms to test the effectiveness of effluent disinfection in a wastewater treatment plant. While these organisms are generally harmless to us, they do live under the same conditions that human pathogens live. Since we cannot test for every pathogen in the effluent, we test for easily detectable indicator organisms. The assumption is that if we kill the indicator organisms then we most likely kill the pathogens during effluent disinfection. The Plant has to meet effluent water quality limits that are identified in a permit that is issued to the City by the Oregon Department of Environmental Quality (DEQ). The Plant does not have daily fecal limits (only monthly) and at this time it is not known if this incident will result in a permit exceedance. However, the City has elected to report this issue on a voluntary basis so that the public is informed and aware of the issue. The operators have investigated the cause and discovered that the plant operational settings were not correctly set for high flows. The City received over 5 inches of rain from Saturday through Monday. As a result, the plant could not keep up with the high flows. The settings have been adjusted and it is not anticipated that this issue will occur when the plant goes into high flow mode in the future. The City reported this issue to the Oregon Emergency Response System (OERS) and DEQ. Any questions can be directed to the City of Coos Bay Public Works Department at (541) 269-8918.
