When customers see water flowing from a fire hydrant, they might think someone opened it by accident or it’s broken. But that may not be the case because sometimes Louisville Water is flushing the hydrant on purpose.
Our water is the highest quality it can be when it leaves our treatment plants, but as water ages and moves through the distribution system, it can change over time. We are required by federal and state regulations to maintain chlorine disinfectant residual throughout the distribution system and to our customers’ taps. By careful study and extensive water quality monitoring, the Distribution Water Quality Department knows the areas in the system that are prone to higher water age and lower chlorine residual. They conduct activities such as hydrant flushing and tank draining to reduce and manage water age in those areas.
These activities happen more frequently in the summer months as higher temperatures can cause water to degrade quicker. The department must also balance pressure and flow requirements while also maintaining the water quality.
“Typically, in the summer we may have about 15 to 25 sites where we conduct some sort of continuous, ongoing flushing activities,” said Casey Doyle, supervisor of Distribution Water Quality.
“Most of these are either fire hydrants, dead end mains or at a tank site to encourage water to turn over in the tank. However, that number can vary depending on a variety of factors including operational changes in the system.”
Over the past several years, these flushing activities have increased and expanded into different areas. This is primarily due to customers using less water for a variety of reasons such as high efficiency appliances and reduced irrigation demands.
To some, flushing may seem like a waste of water, but it is necessary to ensure the highest quality water reaches the customers’ tap.
To make sure that customers know which sites are being monitored, a Water Quality Flushing tag or yard sign is posted at all sites Louisville Water is managing. Louisville Water asks that customers do not tamper with, adjust, or turn off any hydrant or other apparatus that is flushing.
If the flushing is causing a safety issue or property damage, customers can call 502.569.3676.