Premium
Giardia and Cryptosporidium in raw and finished water
Author(s) -
LeChevallier Mark W.,
Norton William D.
Publication year - 1995
Publication title -
journal ‐ american water works association
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.466
H-Index - 74
eISSN - 1551-8833
pISSN - 0003-150X
DOI - 10.1002/j.1551-8833.1995.tb06422.x
Subject(s) - cryptosporidium , giardia , raw water , disinfectant , water treatment , cryptosporidium parvum , filtration (mathematics) , environmental science , surface water , waterborne diseases , environmental engineering , microbiology and biotechnology , biology , waste management , water quality , chemistry , ecology , engineering , mathematics , feces , statistics , organic chemistry
The D/DBP Rule and the ESWTR must be orchestrated carefully to ensure protection of public health. The American Water System has conducted extensive monitoring of its operations since 1988. Analysis of 347 surface water samples collected between 1988 and 1993 showed that the prevalence rate of Giardia and Cryptosporidium was 53.9 percent and 60.2 percent, respectively. But because the parasite assay does not indicate viability or virulence, these results do not necessarily indicate that these water systems were at risk from waterborne pathogens. To supplement coagulation and filtration, the average system will have to apply sufficient disinfection to reduce viable Giardia levels by 3.1 log 10 . An analysis of existing disinfection practices shows that most systems are already applying disinfectant at a level sufficient to reduce Giardia levels. However, the proposed Disinfectants/Disinfection By‐products (D/DBP) Rule may hamper the ability of water utilities to apply sufficient disinfection under current operating conditions. Careful integration of the D/DBP and the Enhanced Surface Water Treatment rule is encouraged.