Hollow fiber ultrafiltration is used to remove virus, Giardia, Cryptos
poridium, and coliform and to reduce turbidity and TOC from surface wa
ters to produce potable water. The application of ultrafiltration tech
nology to the municipal water market is an extension of its success in
a myriad of applications. Hollow fiber ultrafiltration membranes can
produce consistent filtered water from inconsistent feed water sources
without the use of pretreatment. Data will be discussed from four PTS
river water sources having various feed water qualities: Boise River
(Idaho), Medina River (Texas), Cumberland River (Tennessee), and Wishk
ah River (State of Washington). Polysulfone membranes are highly chemi
cally resistant and provide a positive barrier, preventing passage of
microorganisms from the feed to the filtered water. The skinned constr
uction of the hollow fiber ultrafiltration membrane provides a physica
l barrier which removes contaminants and separates them from the treat
ed water stream. Long membrane life is ensured by the use of mechanica
l cleaning techniques, low pressure water backflush, and flow reversal
.