Filtering Out the Rest - Choosing Filter Equipment to Maximize Future Flexibility


  • Jared M. Hartwig PE - Hazen and Sawyer
  • William G. Huggins PE – Charleston Water System

Municipal water treatment plants (WTPs) are under increasing pressure to repair this aging infrastructure while keeping up with increasingly stringent limits.

The purpose of this paper is to highlight the evaluation performed by Charleston Water System and Hazen and Sawyer to rehabilitate the existing Stoney Filter Building at the Hanahan Water Treatment Plant. This evaluation provided recommendations for rehabilitation of the existing filters to replace aged infrastructure while also maximizing the potential for retrofitting this facility for future functionality including for use with Granular Activated Carbon (GAC) or Biologically Activated Carbon (BAC) filtration.

Limitations of the existing facility posed a significant challenge for the long-term feasibility of the structure. Through an evaluation of available filter underdrain technologies, and analysis of the existing facility using Computational Fluid Dynamics (CFD) modeling, CWS was able to create a plan for the existing filters to function well now and into the future.

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Horizons Fall 2017 (pdf)

Horizons showcases significant water, wastewater, reuse, and stormwater projects and innovations that help our clients to achieve their goals, and can help you achieve yours. Articles are written by top engineers and process group leaders, demonstrating and explaining the beneficial application of a variety of technologies and tools.

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