Tuesday, September 10, 2024
2:30 PM - 3:00 PM
Partnering Together for Safe Water: Capacity Evaluation of Louisville Water’s CHWTP
Drinking Water Treatment

Louisville Water is recognized nationally for its commitment to excellent water quality and for proactive and innovative solutions to the challenges of tomorrow. Louisville Water owns and operates the Crescent Hill Water Treatment Plant (CHWTP) which treats raw water from the Ohio River using conventional treatment processes. The CHWTP is the largest treatment plant in Kentucky and has achieved Phase IV status under the AWWA Partnership for Safe Water. The CHWTP has a recognized treatment capacity of 180 MGD based on the results of a water treatment capacity study performed in 2007. However, past upgrades to major treatment processes, present variations in source water and climate conditions, and future commitments to peak water quality compelled Louisville Water to reassess this previous capacity study and obtain fresh insight into optimizing their treatment for both present and future needs. To achieve these goals, Louisville Water engaged HDR to perform a collaborative assessment of the CHWTP which would update the previous capacity study, document all present-day existing conditions, and identify any operational and capital improvements that would achieve a hydraulic and process treatment capacity of 180 MGD or greater while achieving Partnership goals. The work included four main components. The first component included a desktop level capacity evaluation of all pumping systems, treatment units, chemical systems, and storage facilities to compare existing systems with industry standards, regulatory guidelines, and original design criteria. The second component involved a plant-wide hydraulic model which was calibrated using field surveyed water surface elevations throughout the plant at normal flow and high flow conditions and then used to identify hydraulic bottlenecks and determine maximum hydraulic capacity at the plant. The third component included more detailed studies related to the optimization of three major unit processes: Coagulation, Softening, and Filtration. The process optimization studies included bench scale and full-scale testing of optimal chemical dosing and mixing, plant profiling of major water quality parameters, verifications of equipment performance, filter media and backwash evaluations, and “stress testing” of the overall plant as well as the filtration process. The final and fourth component was based on the results of the previous work and included identification of recommended operational and capital improvements as well as future project prioritization and planning. Benefits from the study included identification of hydraulic bottlenecks and mitigation of unintended flow splits within the treatment process, optimized coagulation and mixing for increased turbidity and organics removal during both warm water and cold weather scenarios, enhancements to chemical dosing and mixing to achieve lower softening effluent turbidities, and increases to available filtration rates throughout various changes in seasonal and upstream process conditions. The transparent, supportive, and engaged collaboration between owner and consultant was a crucial component of project success. Louisville Water’s proactive approach to capacity assessment at the CHWTP has provided detailed insight into their existing system and created a roadmap for addressing future treatment needs.