Opportunities and Challenges for A Newly Upgraded 300-mgd Plant – Data Review for the First Year of Operation

The Belmont Advanced Wastewater Treatment (AWT) plant at Indianapolis, IN was built in 1980s. It was a two-stage nitrification facility composed of a bio-roughing process followed by a pure oxygen nitrification system (ONS). The plant was rated at an average capacity of 120 mgd with a peak capacity of 150 mgd. The Belmont AWT plant was upgraded to handle 300 mgd peak flow through its secondary treatment process by the end of 2012. During the plant upgrade, the original two-stage biological nitrification process was converted to a one-stage nitrification process by replacing the deteriorated bio-roughing towers with a new aeration basin. This new aeration basin coupled with the original ONS enabled the plant to treat 300 mgd peak flow without adding additional clarification capacity. This paper was intended to discuss some major opportunities and challenges the newly updated plant is facing by reviewing the data from the first year of operation.