City of College Station

The City of College Station operated a wastewater treatment facility constrained by aging control infrastructure that could no longer keep pace with municipal growth demands. Operating at a capacity of 8.1 million gallons per day (MGD), the facility faced a dual challenge common in municipal utilities: insufficient headroom to serve a growing population and inefficient energy consumption driven by outdated pump and process controls. Without modernization, the city faced the prospect of costly new construction to meet permit requirements, while continuing to absorb unnecessary energy expenditures from equipment that could not be optimized under legacy automation.

The City of College Station partnered with Rockwell Automation to undertake a comprehensive control system modernization of the wastewater treatment facility. The project replaced legacy controls with an integrated automation platform, enabling precise, coordinated management of pumping, aeration, and treatment processes across the facility. Modern programmable controllers and variable frequency drives (VFDs) were deployed to regulate motor-driven equipment dynamically, matching energy draw to actual process demand rather than running at fixed speeds. The updated SCADA and HMI layers gave operators centralized visibility and control over facility-wide operations. This integrated approach allowed engineers to push treatment throughput beyond the original design envelope while simultaneously reducing energy waste — addressing both the capacity and cost challenges within a single modernization initiative.

The modernization delivered measurable gains across both capacity and operating cost:

• Throughput capacity expanded from 8.1 MGD to 11.8 MGD — a 46% increase — without constructing a new facility
• Annual energy savings of $65,000 achieved through optimized motor control and process automation

The capacity expansion deferred what would otherwise have been a capital-intensive construction program to meet regulatory flow requirements. The energy savings represent a recurring operational benefit that compounds over the facility's lifespan. The project was recognized with an industry award, validating the approach as a model for municipal wastewater modernization. Operators gained improved process visibility through updated HMI interfaces, supporting more consistent treatment performance.

• Control modernization can substitute for capital construction: upgrading automation to extract latent capacity from existing infrastructure is often faster and cheaper than building new treatment volume.
• Variable frequency drives are a high-ROI lever in wastewater: matching motor speed to real-time process demand is consistently one of the largest energy reduction opportunities at pump-intensive facilities.
• Integrated platforms outperform piecemeal upgrades: coordinating controls across pumping, aeration, and treatment in a unified system unlocks optimization that isolated upgrades cannot achieve.
• Municipal utilities should quantify energy savings at the project proposal stage: the $65K annual figure provides a tangible payback metric that justifies modernization investment to city councils and rate-payers.