A process improvements evaluation was completed at the City of Cedar Rapids J Avenue Water Treatment Plant (WTP). Originally constructed in 1929, with upgrades and expansions occurring in 1949, 1967, and 2009, the J Avenue plant has begun to experience age-related issues not readily correctable through preventative maintenance. The City identified several critical processes for further evaluation. Our mission was to identify improvements to maintain reliable and efficient water production and treatment for the next 50 years.

We evaluated and recommended improvements for the following components:

• Existing lime softener clarifier basins
• Automation of the dosage systems for chlorine, carbon dioxide, fluoride, and zinc-orthophosphate
• Existing lime slaker system
• Existing lime lagoons
• Existing backwash supply piping
• Filter backwash process
• Filtration technologies
• Existing sludge dewatering process
• Chemical storage space for chlorine, carbon dioxide, fluoride, and zinc-orthophosphate

The study included at least two alternatives for each component. The alternatives were evaluated by examining both monetary considerations and non-monetary considerations. The monetary considerations included capital, operational, and maintenance costs during a 20-year total present worth. Nonmonetary considerations included performance, operations, maintenance, and complexity to implement. The study also included a phased approach to each alternative to limit impact on plant operations. The opinion of probable cost for the recommended improvements was approximately $37 million and broken down into five phases.