The Wastewater Treatment Plant in Catlin, Illinois, needed upgrades to improve capability, reliability and flexibility. The plant was built in 1977 and partially improved in 2001, but it required more updates to ensure it complied with Illinois Environmental Protection Agency standards. So, in 2016, the Village hired Fehr Graham to prepare a facility plan and design the improvements.
Our team proposed improvements to increase peak capacity and allow more flexibility to manage dry weather and excess flows. We also suggested replacing most of the major pieces of equipment to increase reliability. The system has a large amount of inflow and infiltration, which creates periods of high flows that push the plant’s capacity limits. To achieve excess flow treatment, Fehr Graham recommended Influent pump station improvements and suggested refurbishing the conventional activated sludge package plants, chlorine contact tank, aerobic digesters, sludge drying beds and control building. We also recommended the Village convert the inner clarifiers from the activated sludge package plants to aerobic digesters and build two clarifiers.
Construction began in October 2019 and is expected to be completed in November 2020. The plant will continue to serve Catlin while the upgrades are made. Construction won’t affect the nearby wetlands or infringe on the floodplain. The improvements will have a positive effect on a nearby tributary to Butler Branch Creek because of the facility’s increased reliability, and the increase in capacity will ensure the plant is compliant for an additional 20 years. The improvements are expected to cost $10.8 million, so Fehr Graham helped the Village find funding for the project. In March 2019, the United States Department of Agriculture Rural Development Office gave Catlin an $8 million loan and $2.8 million grant to pay for the improvements, making the upgrades more affordable for residents.