AWWA ACE56366

During the summer and early fall of 2001, higher than usual raw and treated water manganese levels were detected at the District Municipality of Muskoka MacTier Water Treatment Plant (WTP) located in Ontario, Canada. The elevated treated water manganese levels produced aesthetically unpleasant water once distributed throughout the distribution system. While in the distribution system, the dissolved oxygen in the treated water slowly oxidized the dissolved manganese into a particulate form and as a result imparted a black/brown color to the water. The oxidation of the manganese also resulted in the formation of a brown deposit/coating in the analytical instruments at the WTP, and thereby requiring the plant staff to clean and maintain instruments more frequently. During the same time period, higher than usual manganese levels were also detected at the Bala WTP. By pre-chlorinating the raw water at the Bala WTP, manganese levels were reduced to acceptable levels. This form of pre-treatment however did not sufficiently reduce the manganese levels at the MacTier WTP. In order to understand the occurrence of the sudden rise in manganese concentrations, an extensive study was undertaken to investigate the source of manganese and to establish factors that contributed to the sudden rise in manganese levels. The scope of the study was later expanded to determine a treatment approach that could be applied to reduce manganese concentrations at the MacTier WTP. Includes table, figures.

Product Details

Edition:

Vol. - No.

Published:

06/16/2002

Number of Pages:

10

File Size:

1 file , 380 KB