The Iowa Department of Natural Resources (IDNR) is the governing body of community water systems like that of Asbury’s.  The IDNR mandates that to be “safe for human consumption”, a water supply must, at all times, maintain a minimum .3 mg/L free chlorine residual or a 1.5mg/L total chlorine residual throughout the water distribution system.  To maintain a .3 mg/L free chlorine residual, a system must attain breakpoint chlorination.

In early October 2019, the City of Asbury Water Department began moving the water supply toward what is known as “breakpoint” chlorination.  This decision was made, in conjunction with the IDNR, based on Asbury’s historical water quality parameters and residual chlorine levels. A host of challenges can often accompany the process of moving to breakpoint chlorination.  One of those challenges is the formation of tastes and odors in the water supply.

Some of our customers have reported a “bleachy” smell coming from the water.  While people are usually quick to blame that on an excess of chlorine, it is actually an indication that more chlorine should be added to achieve breakpoint.  Without going into a very in-depth and a complex lesson in water chemistry, the “bleachy” odor and/or taste comes from the formation of dichloramine when the chlorine reacts with certain constituents in the water.  Once breakpoint is achieved, the taste and odor should subside.  Reaching breakpoint chlorination is sometimes a very challenging and lengthy endeavor.

The Asbury Water Department is giving this issue its full attention.   As we’ve collected more data, made numerous adjustments to our chemical feed rates, and consulted with the IDNR, the challenges have more clearly presented themselves.  At this time, Asbury Water will be moving the water back to the total chlorine residual disinfection level of 1.5 mg/L.  This should help eliminate most, if not all, of the taste and odors you are experiencing. 

The City of Asbury Water Department, at all times, holds consumer safety to the utmost importance.  During this process, the City’s water has remained SAFE and met all IDNR standards.  The Asbury Water Department thanks our customers for their patience and does apologize for any inconvenience this transition may have initiated.  In the future, Asbury Water will continue to strive to improve the City’s water quality at the tap.