FAQs - Water Quality and Public Health

Cryptosporidium

Cryptosporidium is a microscopic protozoan that when ingested, can result in diarrhea, fever, and other gastrointestinal symptoms. The organism is found in 97% of all surface water sources including lakes, rivers and streams.

On April 7, 1993, the City of Milwaukee issued a boil water advisory on the probability the illness-causing micro-organism Cryptosporidium had passed through the city’s drinking water treatment system and into the finished water. After seven days, the advisory was lifted, and Milwaukee officials vowed there would never again be a waterborne illness event. The City has kept its pledge to upgrade the Milwaukee Water Works (MWW) water treatment and delivery system and improve water quality monitoring. Milwaukee's drinking water meets or exceeds all Wisconsin Department of Natural Resources (DNR) and U.S. Environmental Protection Agency (EPA) standards. The Milwaukee Water Works conducts a rigorous water quality monitoring program to ensure safe, healthy water and to gather data to assist regulators in setting standards for emerging contaminants. 

The events of 1993 led to improvements worldwide in water quality treatment processes, water quality monitoring, and regulations to protect the public health. In particular, the ongoing partnership between the MWW and the Milwaukee Health Department for water quality monitoring and public health surveillance, ground-breaking at the time, is now recognized nationally for its effectiveness in protecting public health. The Interagency Clean Water Advisory Council developed an early warning disease surveillance network and procedures to notify the public and respond in the event of drinking water contamination or a disease outbreak.