Recently there have been news articles on arsenic in drinking water. This is a concern for water systems that use ground water from wells as a source. The Sheboygan Water Utility uses Lake Michigan as a source and not ground water. Recent tests showed no detection of arsenic in Sheboygan’s drinking water at levels less than 100 parts per trillion, which is the sensitivity level of current test methods. See
http://dnr.wi.gov/files/PDF/pubs/DG/DG0062.pdf more information on arsenic in drinking water.