The Andover Department of Public Works today provided an update on recent intermittent discolored water throughout the water distribution system. The Department is reporting significantly fewer reports of discolored water to the Department today than in recent days.
Due to the prolonged period of high temperatures this summer, the demand in the water system is at near record consumption, causing areas of discolored water throughout the distribution system. The issue naturally dissipates with increased rainfall and cooler temperatures.
“This problem is caused by very high demand. Our August 2018 consumption to date has seen an increase of nearly 10% over last year. That is coming off increased usage of over 20% this past July over that of 2017", said Town Manager Andrew Flanagan.
Similar to when fire hydrants are flushed, the water velocity increases during peak demand, which causes sediment in the bottom of water mains to become suspended. This results in the discoloration some residents are seeing in their taps. When the velocity slows down, the sediment settles, only reappearing during the next high demand period.
Beginning in the fall of 2014, the Town of Andover instituted a unidirectional flushing program. This program greatly reduces the frequency and severity of discolored water within the distribution system. In addition, Andover also doubled its investment in water main replacement projects, focusing on the replacement of the community’s oldest unlined cast iron pipes. This proactive infrastructure work will further assist the system in future years.
“Please be assured, Andover’s drinking water supply is safe and there is no public health risk. This is an aesthetic issue caused by manganese precipitate. We appreciate the public’s patience as this issue does not completely correct itself overnight,” added Director of Public Works Chris Cronin.