Wisconsin Administrative Code
Department of Natural Resources
NR 800 - Environmental Protection - Water Supply
Chapter NR 810 - Requirements for the operation and maintenance of public water systems
Subchapter II - Surface Water Treatment and Groundwater Under the Direct Influence of Surface Water Treatment Operations
Section NR 810.35 - Cryptosporidium treatment requirements for filtered systems

(1) Filtered systems shall provide the level of additional treatment for Cryptosporidium specified in this paragraph based on their bin classification as determined under s. NR 810.34 and according to the schedule in s. NR 810.37.

(2) Systems shall use the following treatment or management practices:

(3) Failure by a filtered system in any month to achieve treatment credit by meeting criteria in ss. NR 810.41 to for microbial 810.46 to olbox options that is at least equal to the level of treatment required in sub. (1) is a violation of the treatment technique requirement.

(4) If the department determines during a sanitary survey or an equivalent source water assessment that after a filtered system completed the monitoring conducted under s. NR 809.331(1) or 809.331(2), significant changes occurred in the system's watershed that could lead to increased contamination of the source water by Cryptosporidium, the system shall take actions specified by the department to address the contamination. These actions may include additional source water monitoring or implementing microbial toolbox options listed in s. NR 810.41, or both.