Sussex Borough water is not contaminated despite recent reports of water discoloration throughout the borough, Business Administrator Toni Smith announced last Friday.
The Borough has been investigating the cause, and has found that during random periods, there have been significant increases in flow for short periods of time during the day. One of the causes of these spikes has been determined to be caused using hydrants with extremely high volumes over brief periods of time. Fire hydrants can produce large amounts of flow, and if they are operated too quickly their use can cause upsets with water quality in the distribution system.
The most recent occurrence was on July 18, and these spikes caused distribution system flows rates to increase from 150,000 gallons per day, to flow rates in excess of 1.2 million gallons per day. There were 10 spikes over a 90-minute period, which caused extreme scouring of the distribution piping. The borough found the cause of these spikes on July 19 and began an extensive flushing program over the next several days to drain the discolored water and bring fresh water into the system.
The source of the rusty water is the long-term buildup of sediments and corrosion of the water mains. The treatment plant has continued to operate well within the regulatory parameters during this entire period, Smith said. The brown discoloration is caused by iron deposits, and although aesthetically displeasing, is not considered harmful. Samples taken in the distribution system have shown this, and a proper disinfectant residual has been continuously maintained by the treatment plant operations staff.
Borough officials anticipate that recent system flushing will eliminate the problem, but advised that any flushing event, planned or unplanned, will cause temporary disturbances and the system will need time to recover.
The borough has recently taken bids for the first water main cleaning and relining project, which will remove sediments and rust that has built up in the water main during the century it has been in use and will also prolong the useful life of the water main.
The treatment facility itself met the short-term, high-volume water demands without a problem. The water supply remained in full compliance with all regulatory requirements despite the stress of dealing with extremely high demands, Smith said.