Disinfection By-Product Reduction Using Clearitas®

Problem

The municipality of Ripley, West Virginia supplies South Jackson County’s water. South Jackson County was encountering problems within the water distribution system, which were aggravated by the long distribution distances and various rates of flow. They looked to Blue Earth Labs to help improve their disinfection by-product (DBP) levels in their water distribution system to remove scale and reduce chlorine demand.

Solution

To treat DBPs within South Jackson County’s water distribution system, Blue Earth Labs fed Clearitas in conjunction with traditional free chlorine. After chemically treating their infrastructure online with Clearitas, South Jackson County conducted a study to determine DBP levels.

During the study, DBPs were measured at six points within the water distribution system. HAA5 levels went down almost immediately at five of the six sites after the addition of Clearitas. THM levels were reduced at four of the six sites but at a much slower rate. In this particular system, the farthest point from the injection site saw little improvement in THM levels, but immediate improvement in HAA5 values. This might suggest that TTHM and HAA5s are formed at different rates and/or locations and that Clearitas either has direct (by interfering with the formation of the components or by destroying them after formation) or indirect (through removal of surface deposits) effects in this particular water distribution system.

Results

Overall, a very low dosing of Clearitas was extremely effective at decreasing the DBPs in the problem portions of South Jackson County’s water distribution system. Scale was removed fairly quickly near the injection point. As scale was removed from the system, Clearitas gradually began cleaning the pipes further out in the distribution system. By removing the organics that react with chlorine, DBPs continued to decrease and chlorine residuals stabilized, improving the overall quality of South Jackson County’s municipal water supply.