Utility managers looking for strategies to assess pathogen
removal by filtration with tools that are easier to use and
more cost-effective than monitoring Cryptosporidium parvum
directly will find this article of interest. The article discusses how
oocyst-sized microspheres are easier, safer, and less expensive to
work with than Cryptosporidium parvum and are also a reliable
tool for assessing C. parvum removal by filtration. It also shows
that the ability of filters to remove C. parvum is not the same
during all phases of the filter cycle. Even when a filter is in compliance
with drinking water regulations, its C. parvum removal
capacity can be substantially worse near the end of a filter cycle
compared with the earlier portions of the cycle.
This work also emphasizes that process evaluations must
consider all operating periods, not just optimized operation. Further,
it suggests that there can be a real difference in water
quality even when differences in turbidity are very small. Includes 16 references, table, figures.