California Code, Health and Safety Code - HSC § 116360

(a) The department shall take all reasonable measures it determines necessary to reduce the risk to public health from waterborne illnesses in drinking water caused by cryptosporidium and giardia, to the extent those micro-organisms are not yet able to be adequately controlled through existing drinking water treatment and other management practices.

(b) The department shall directly conduct, or order the state's public water systems to conduct, comprehensive sanitary surveys, as present resources permit, to identify risks to public health from cryptosporidium and giardia.

(c) To thoroughly address the public health risks currently posed by cryptosporidium, in particular, the department shall ensure that its initial cryptosporidium action plan, that has been circulated to public water systems serving more than 1,000 service connections, is comprehensively implemented and shall devise and implement necessary strategies for protecting the health of individuals served by smaller public water systems from cryptosporidium exposure.