Manganese Advisory

During routine water quality sampling in 2006, two of the City’s 21 wells exceeded the California Department of Health Services (DHS) established Secondary Maximum Contaminant Level of 50 ppb (parts per billion) for Manganese. A Secondary Standard is established for aesthetic reasons only and is not considered a health hazard. As required by law, the City is required to inform the consumers that these wells have exceeded the limit.

Manganese may cause discolored water. The two wells that contain high levels of Manganese are Well 15, located at 1812 Manzanita Drive, and Well 30, located at 1819 Lake Boulevard. These wells contained levels of 73 ppb and 98 ppb, respectively.

We will continue to use these wells as needed as we are in our peak demand season and must operate these wells in order to maintain system-wide pressure. These two wells will be tested monthly for Manganese so that we may observe any potential trends towards increasing levels. Typically, groundwater sources are only required to be tested every three years for constituents such as Manganese.

For more information about Manganese, please visit the DHS’ web site at http://.dhs.ca.gov/ps/ddwem/chemicals/Manganese/notificationlevel.htm; or call the City of Davis’ Public Works Department at 530-757-5686 if you have further questions about our source water.