The Village of Archbold has a 7.6 mgd surface water treatment plant and serves several outlying communities. Recent struggles with THM’s and an aging plant led the Village to seek out Jones & Henry to development a plan to reduce THM’s and upgrade the aging infrastructure. We started the process with a complete plant evaluation, proceeded with a granular activated carbon (GAC) pilot study, completed a preliminary engineering report (PER) and final design, performed construction administration services and assisted with startup and operation of a new 7.6 mgd GAC and ultraviolet disinfection (UV) facility for the Village.
The plant evaluation and PER entailed a full process and equipment evaluation, filter media study and recommendations for plant improvements. During this time a GAC pilot study was also completed to determine the most effective GAC media to reduce total organic carbon and ultimately system THM’s. We worked with the Village and Ohio EPA on developing the pilot protocol and a General Plan for all water treatment plant improvements.
Construction on the project was completed in June of 2022. Total improvements include converting a gaseous chlorine system to sodium hypochlorite; replacing existing gravity filter media and adding an air scour system; other chemical feed improvements; a new GAC and UV facility; adding mixers to two existing clearwells; SCADA upgrades; and additional site and yard piping design. Jones & Henry completed the process, site, architectural, structural, mechanical, electrical and controls design. As the new GAC and UV facility was coming online, Jones & Henry completed an Optimization Study on the current plant processes. The goal of the study was to reduce TOC and improve overall water quality before water enters the GAC facility. Through jar testing and other observations, the change in lime supplier yielded significant improvements in clarification, filter run times and reducing TOC through the initial plant processes.
Within three months of the new GAC facility being online the Village was in compliance with TTHM regulations and all test sites running annual average was reduced to less than 80 ug/L.
Jones & Henry continues to monitor water quality results after the completion of the project to assist the Village optimizing the life of the GAC media. This optimization plan has helped extend the life of the media before regeneration is required, saving the Village change out costs.
