AWWA WQTC64136

In order to determine the effectiveness of a disinfectant residual against anaccidental microbial intrusion, an extensive literature review of numerous studiesspecifically investigating the fate of microorganisms introduced into experimentalsystems (laboratory- (or bench-), pilot-, and isolated full-scale) has been conducted. Inthese experiments, various types of microorganisms are used, including pathogenic ones,in the presence or absence of a disinfectant residual. Depending upon the experimentalsetting, monitoring of the organisms is performed in the bulk water and/or the biofilm.This review shows that the conclusions about the efficacy of a disinfectant residual toprotect against pathogen intrusion are not converging. The laboratory- and pilot-scalesystems lead to different observations regarding the persistence of microorganisms inbiofilms. The most critical conditions in terms of persistence of microorganisms in awater system could be identified when the intrusion takes place under no or low flowconditions (such that the microorganisms can accumulate in the biofilm), and when adelay is achieved between the time of intrusion and the onset of chlorination. Includes 37 references, tables.

Product Details

Edition:

Vol. - No.

Published:

11/01/2006

Number of Pages:

14

File Size:

1 file , 410 KB