Riverbank filtration (RBF) offers water suppliers an
alternative treatment option for the control of
disinfection byproducts (DBPs) and microbial
contaminants. In the process of RBF, water infiltrates
and travels through aquifer sediments, undergoing a
combination of physical, chemical, and biological
processes that can significantly improve raw water
quality. Although RBF has been extensively used in
Europe for many years, it has only recently attracted
interest and support among US utilities.
This study monitored the fate of DBP precursors
and selected microorganisms during RBF at three Midwestern
US drinking water sites. Results demonstrated
that RBF was successful at controlling DBP formation
and provided a barrier to microbial contamination of
drinking water supplies. With RBF, all three sites experienced
significant reductions in total organic carbon,
dissolved organic carbon, and DBP precursors.
The US Environmental Protection Agency is currently
considering assigning Giardia and Cryptosporidium
treatment credit to RBF in the development of the
Long-Term 2 Enhanced Surface Water Treatment
Rule. This research gives utilities and legislators data
to confirm RBF as an effective treatment option and
support the application of treatment credits to the
process. Includes 60 references, tables, figures.