Below is a list of free resources on the management of dissolved oxygen in activated sludge plants to supplement our previous article Managing Dissolved Oxygen in Activated Sludge Plants . Troubleshooting Noncompliance at Small Wastewater Treatment Plants This is a 171-page presentation from the Ohio EPA on Troubleshooting Noncompliance at Small Wastewater Treatment Plants that features information on activated sludge process control. Operating Tools and Measurement Techniques for Troubleshooting Activated Sludge Systems This 29-slide presentation discusses tools that can be used to troubleshoot activated sludge systems. The presentation will introduce some simple tools, talk about some that are a little more advanced, and show operators that this is not the realm of only the laboratory or the engineer. Activated Sludge Process Control Manual This is a 106-page Activated Sludge Training Manual that was prepared by the Michigan Department of Environmental Quality with information on operating the activated sludge process, including nutrient removal, and troubleshooting. Holistic Aeration and Chemical Optimization Saves Big Money from 1 MGD to 600 MGD This 36-slide presentation outlines automated dissolved oxygen control, which includes reduced operator labor/attention, improved process stability, and energy savings; automated biomass control; and automated chemical feed control for P removal, which includes a 95 percent reduction in chemical usage. Troubleshooting Activated Sludge Processes This 32-slide presentation discusses how to troubleshoot activated sludge processes and covers process types & kinetics, influent monitoring, process monitoring, and control and nitrification. Convert Activated Sludge to BPR This 48-slide presentation discusses improving Bio-P performance by getting to know the system, initial assessment, expanding a zone for increased BPR performance, learning D.O. control, and more. Efficient Nutrient Removal under Low Dissolved Oxygen Concentrations This 25-slide presentation discusses the City of St. Petersburg Southwest WRF, City of Rochester WWTF, and more. Activated Sludge- It’s About Efficiency and Optimization This 167-page compilation of eight presentations discusses the history and application of activated sludge, aeration systems, secondary clarifier design and operation, aeration efficiency studies, dissolved oxygen control, blower technologies, advancements in control systems for WWTPs, and conversion to MBR. Doom & Bloom: Biochemical Oxygen Demand (BOD) in Wastewater Treatment This website from the Environmental Finance Center Network provides an overview of the function of biochemical oxygen demand in wastewater treatment plants. A Tale of Two Filaments: BNR System Recovery from a Major Process Upset This 7-page article discusses the Glendale Wastewater Treatment Plant in Lakeland, Florida that had a power outage that caused the dissolved oxygen concentrations in the aeration basins to drop very low. These resources and more can be found in our document library .