AWWA JAW49836

European and North American water utilities and regulatory agencies were surveyed to determine current drinking water monitoring practices for Giardia cysts and Cryptosporidium oocysts and to ascertain how the monitoring data are used. Responses from 27 agencies indicated that monitoring is still generally voluntary, except in the case of disease outbreaks, during which regulatory agencies can require testing. The data are used to study the occurrence of protozoa in source water, to assess treatment efficiency, and to support investment planning. Rarely are these data used to make public health decisions and then only in conjunction with other data such as weather-watershed changes, treatment information, other water quality parameters (i.e., turbidity), and presence of disease in the community. The primary reason protozoan monitoring data are not used in public health decision-making is lack of reliability of the data quality. Includes 23 references, tables.