Some residents have called the office or posted on social media about discolored water, chlorine smell or metallic taste recently. I’m happy to report that everything should be cleared up by the end of next week.

Providing safe, great tasting water is our number one priority. Roxborough’s water remains safe and clean. It starts as a pristine mountain supply and is treated in the community’s state-of-the-art treatment plant. The recent discoloration was caused by a process change to complete routine maintenance of the distribution system. We apologize that this change impacted the appearance, taste and odor of the water. We have tested the water regularly throughout this period and all test results have been well below regulatory limits set by the State of Colorado and U.S. EPA.

In the spring of 2018, RWSD changed its disinfection residual from free chlorine to Chloramination. We did extensive outreach to prepare the community for this change and completed it in conjunction with our annual spring flushing program. RWSD uses ultraviolet light (UV) as the primary disinfection process at the water treatment plant but relies on a chlorine residual to maintain the disinfection residual in the distribution system. Chloramination is a much more stable disinfection residual and is less likely to form disinfection byproducts; it also does not have the chlorine smell or taste that free chlorine can cause.

In early November, when water use dropped off dramatically after the high demand summer season, portions of the distribution system were showing signs of extended water age. This can sometimes cause a biofilm to develop in the tanks and distribution pipes. To combat the problem, the District changed our disinfection residual back to free chlorine in mid-November. This is a process known as a chlorine flush and it is a recognized best practice for eliminating any biofilm that may have formed. Unfortunately, even though the chlorine dose is low (between 1.5 – 2.0 mg/L, well below the regulatory limit of 4 mg/L), many people noticed the smell of chlorine and a metallic taste. As the chlorine flush successfully cleaned the biofilm in the system, residents began reporting discolored water in addition to the taste and odor issues.

Even though the water remains safe to drink, we consider discolored water to be unacceptable. That’s why we ask residents to contact us immediately should they experience discolored water, so that we can immediately flush the system until the water runs clear. They should not wash any clothing before running their cold water for 5-10 minutes to clear any remaining discolored water from the pipes inside the house.

The issues RWSD has experienced the last several weeks are not unusual or unique to Roxborough. We are updating RWSD’s monitoring plan and making modifications to its operating plan to avoid this situation in the future. Please contact us should you experience discolored water or have any questions, as we are here to help.