AWWA QTC98297

Wisconsin experiences unexplained peaks in total coliform positivity in the late summer and early fall which results in a rash of "boil water" orders and other regulatory activities. This study gathered data to help explain this phenomenon. Approximately sixty-five, non-community public water supply wells located throughout Wisconsin were sampled monthly for one year. Water samples were tested for coliform bacteria as well as biofilm indicators such as iron bacteria, heterotrophic plate count bacteria and water temperature in an attempt to better understand the relationship between biofilms in distribution systems, seasonaltiy and coliform regrowth and colonization. Analysis of the entire set indicates a high correlation between elevated temperatures and total coliform positivity. Analysis of the influence of the presence of biofilms on total coliform positivity indicates a strong connection. Small well water systems with biofilms present have a much higher likelihood of coliform positivity when water temperatures rise in late summer than wells where biofilm were not present.

Product Details

Published:

01/01/1998

ISBN(s):

0898679796

Number of Pages:

7

File Size:

1 file , 44 KB