Record Display for the EPA National Library Catalog


Main Title Impact of Wet-Weather Peak Flow Blending on Disinfection and Treatment: A Case Study at Three Wastewater Treatment Plants.
Author R. B. Rukovets ; B. J. Mitchell
CORP Author Interstate Environmental Commission, New York, NY.; National Risk Management Research Lab., Edison, NJ. Water Supply and Water Resources Div.; National Risk Management Research Lab., Cincinnati, OH. Office of Research and Development.
Year Published 2010
Report Number EPA/600/R-10/003; EP06C000010
Stock Number PB2011-113247
Additional Subjects Storm water runoff ; Microbiological impact ; Blending ; Effluent flows ; Bacteria sampling ; Protozoa sampling ; Virus sampling ; Storm sewers ; Recommendations ; Flow rates ; Bacterial indicators ; Maceration ; Wet weather flow treatments ; Wet-weather flows at wastewater treatment plants (WWTPs) ; Environmental Protection Agency ; New York City (New York) ; Biological treatment units ; Permitted outfalls
Library Call Number Additional Info Location Last
NTIS  PB2011-113247 Some EPA libraries have a fiche copy filed under the call number shown. 07/26/2022
Collation 78p
Blending is the practice of diverting a part of peak wet-weather flows at wastewater treatment plants (WWTPs), after primary treatment, around biological treatment units and combining effluent from all processes prior to disinfection and subsequent discharge from a permitted outfall. For combined sewer systems, EPA's 1994 Combined Sewer Overflow (CSO) Policy encourages delivery of maximum flows to WWTPs, while ensuring that bypasses do not result in National Pollution Discharge Elimination System (NPDES) permit exceedences. Consistent with that principle, blending of flows at WWTPs serving combined sewer systems presents one of the more technically practicable and economically feasible alternatives. In addition, in December 2005, the EPA proposed, for public comment, a new policy for addressing peak flow events at municipal WWTPs served by separate sewer systems, also through flow maximization. This project's intent was to determine the microbiological impact of blending primary effluent flows that are in excess of secondary treatment capacity with the secondary effluent prior to disinfection at large municipal WWTPs. This approach is typically used by a number of municipal WWTPs within the Interstate Environmental Commission's (IEC) jurisdiction during wet weather to maximize the flow to the WWTP and reduce CSO events. The primary objective of the study was to evaluate the effect of wet-weather blending on the concentration of fecal coliform and Enterococcus indicator bacteria, total residual chlorine, protozoa and viruses in the WWTP final effluent. Three New York City WWTPs were monitored for this project. The project was important for better predicting and understanding the impact of blending on CSO pollution control and receiving water quality.