Expanding a Water Treatment Plant for the town of Bayfield, CO

The Challenge

In a joint effort, the Town of Bayfield and La Plata Archuleta Water District (LAPAWD) partnered together on the expansion project of the existing 1.5 MGD Bayfield Water Treatment Plant (WTP). The WTP already included two ACTIFLO + Multimedia Filter (MMF) treatment trains originally commissioned back in 2003. An expansion to the facility of 1.0 MGD was necessary to accommodate the growing demands for the town as well as expanding the potable water supply within La Plata County.

The Solution

The combination of Veolia’s ACTIFLO high-rate ballasted clarification process and Veolia’s DUSENFLO™ multimedia filters were chosen for the expansion at the Bayfield Water Treatment Plant.

While influent sources for the WTP have been relatively stable, there have been periods of high turbidity, color, and organics that have resulted in treatment challenges. Following an extensive evaluation by the Briliam/FEI Engineers (acquired by Plummer in 2019) looking at a variety of options, and given both the current conditions as well as potential future challenges, the ACTIFLO system was chosen based on proven performance along with operational familiarity with the process. In addition, the Veolia MMF offering (DUSENFLO™) was chosen in combination with ACTIFLO, which provided the Plant with a proven single-source responsibility that resulted in the most economical solution for both the Town of Bayfield and LAPAWD.

Project design and construction in addition to the expanded treatment train, included upgrades to the intake structures and building modifications including room for future expansion, all while ensuring the existing plant remains in operation and the new ACTIFLO + DUSENFLO™ treatment train was successfully commissioned.
 

Process Description

ACTIFLO® is a high-rate, compact clarification system that utilizes the combination of coagulation, flocculation and sedimentation using microsand as a seed for floc formation. The microsand provides surface area that promotes and enhances flocculation and acts as a ballast to enable rapid settling of coagulated material.

ACTIFLO® has over 25 years of operating experience with drinking water clarification with more than 125 US installations and over 400 installations globally.

The DUSENFLO™ gravity media filters make use of an underdrain design that allows for optimum hydraulic distribution across the filter surface to maximize cleaning efficiency, resulting in a reduction of power and treated water consumption during backwash. The filter media can be tailored to specific conditions and when combined with ACTIFLO® , this packaged treatment train can handle a wide variety of influent conditions while producing easily disinfected finished water. These processes are standardized and delivered pre-assembled resulting in a simple and cost-effective water treatment solution for a variety of municipal and industrial applications.

Results

The Bayfield WTP influent sources are relatively stable throughout the year, however, they are prone to variations in turbidity, color, and organics which at times in the past have been difficult to treat. Of primary concern was the seasonal variations that have often influenced water quality from the Vallecito Reservoir and impacted the overall plant operation. The resiliency of ACTIFLO® as a compact, efficient clarification step prior to media filtration provides the WTP with a solution to handle current conditions while providing proven flexibility that can accommodate potential future problems associated with climate change (forest fires, flooding) or changes in regulations (pesticides).

Veolia’s combined offering of a high rate ballasted clarification process plus multimedia filter (ACTIFLO® + DUSENFLO™) has been a successful addition to the Bayfield WTP. These two established processes have provided the Town of Bayfield and LAPAWD with a process train that is proven and easy to operate.

Ron Saba, Water and Wastewater Plant Superintendent, noted, "This project was really a team effort (Plant Staff, GT Environmental, LLC, Integrated Water Services, Inc, Veolia) and we're very appreciative of Veolia's support in helping to make this a near-perfect project."