Lessons from the Silica "Decline" in Lake Michigan

Abstract

A new analysis of data obtained from water treatment plants on Lake Michigan fails to support published contentions, based on such data, that the silica content of the lake has declined during the last five decades. The purported silica decline appears to have been due to changes in analytical methods and laboratories. Had such changes been avoided, an invaluable record of the silica content of the lake could have been obtained.