The Colony, TX

In 2005, The Colony installed BioWeb in their 2 train, concentric ring plant. They needed to expand capacity by 33% from 3.4 million gallons per day (MGD) to 4.5 MGD. Additionally, they needed to nitrify year round to below 3 mg/l. The first train of 12 modules was installed and began service within 24 hours of initial draining. In 2006, the BioWeb modules were converted to run in the Webitat mode.

The Colony saved over $1,000,000 in aeration basin construction costs by choosing to modify and augment their existing basins with IFAS media. A conventional plant would have experienced excursions in BOD effluent standards as a result of running with only one train during construction. For the previous 7 years, the plant had been unable to run with a single train. However, the IFAS system implemented at The Colony helped the facility maintain permit compliance by placing 12 BioWeb modules in the first train and returning it to service within 24 hours. This gave the plant time to take the second train down for 6 months while converting the basin from contact stabilization to standard activated sludge. Once the conversion of the second train was complete, the first train was taken down for the conversion.

Overall plant performance has been excellent and the facility has exhibited a robust ability to challenging hydraulic conditions and loadings, especially for a high rate system. Ammonia concentrations continue to remain well below the 3 mg/L permit limit and plant staff are fine tuning the biological phosphorus removal system to consistently maintain performance below 1mg/L.