ECM-1 Influent Flow Equalization

• Assess condition of existing welded equalization tank. (The tanks were found to be in good condition but will need to have spots recoated. Some supports will need to be replaced before the spot repairs.)
• Review plant flow records and confirm size of equalization tank(s). (The flow of the plant will not change. The addition of the equalization basin will allow flow into the aeration basin to be consistent.)
• Develop hydraulic profile from lift station through new screen, grit removal, and proposed equalization tanks. (This was completed, and it was determined that a 12-inch discharge line would be adequate to handle normal high flows. Flows that exceed the plant's hydraulic capacity will still need to be handled by bypassing a portion of the influent flow.)
• Develop cost comparison of rehabilitating existing welded tank with new liner or new coating; constructing two new concrete tanks; and constructing two new glass-coated bolted steel tanks. (It was found to be most cost-effective to rehabilitate the existing tanks.)
• Develop preliminary size and description of major equipment items, including blowers and enclosure, transfer pumps, coarse bubble diffusers, valves, process instrumentation, and piping. (This is under consideration and will be completed in the 90% design. At this time we are evaluating choices given to the CCSD WWTP (Wastewater Treatment Plant) for these processes. )

ECM-2 Influent Lift Station Modifications

• Review plant flow records and confirm design criteria for new pumps. (This has been completed, and CCSD WWTP personnel have approved these pumps.)
• Develop system curve for influent lift station and four (4) priority collection system pumps. (The only change at the influent lift station will be the addition of a baffle to break up the cascading water coming from the collection system.)
• Evaluate potential wet well improvements for influent pumps including baffling to improve flow distribution. (Baffling will be installed.)
• Evaluate potential improvements for collection system pumps. (Due to the final cost of the project, most of the lift stations were removed. We have been working on moving lift stations B-1 and B-4 back into the program.)
• Review and confirm options for pump type with District staff. (Evaluation and consideration for lift stations B-1 and B-4 are currently underway.)
• Confirm number and flow range of pumps over a range of motor speeds. (Evaluation and consideration for lift stations B-1 and B-4 are currently underway.)
• Develop preliminary size and description of major equipment items, including new pumps, process instrumentation including flow meter(s), and piping. (Evaluation and consideration for lift stations B-1 and B-4 are currently underway.)
• Develop scope of work and design to integrate collection system pumps into SCADA system. (Lift stations 8, 9, A-1, and B will be added to the new SCADA controls.)

ECM-3 Modified Ludzak-Ettinger Process Upgrade

• Review plant flow and water quality records and confirm design criteria. (Consultant has completed this task and used that information to size the diffusers accordingly.)
• Confirm proposed anoxic and aerobic basin size and configuration from prior studies. (This has been completed, and now discussion on the material to be used is under consideration. )
• Determine recirculation and waste activated sludge flows and aeration requirements under a range of operating conditions. (CCSD WWTP staff has approved the diffusers recommended and the recirculating pumps recommended.)
• Develop preliminary piping and mechanical plan for review by District staff. (This was completed in the 70% design drawings supplied in September 2023.)
• Develop preliminary size and description of major equipment items, including new anoxic mixer(s), diffusers, valves, process instrumentation, and piping. (Most of this has been addressed.)

ECM 4 – Blower System Improvements

• Determine range of air requirements under various influent loading conditions based on analysis in ECM 3. (This has been completed and the blowers will be ordered after CCSD WWTP staff approves the purchase. Blowers have been submitted and approved.)
• Develop description of process instrumentation (including air flow meters and dissolved oxygen probes). (Design is complete, and we will be using two DO (dissolved Oxygen) meters, and ORP (Oxygen Reduction Potential) will be used.)
• Evaluate options for upgrading / retrofitting blower system. (Blowers will be ordered as soon as CCSD WWTP staff approve the purchase. )
• Develop scopes of work and preliminary design for recommended upgrades/retrofit. (Work in progress.)
• Develop new sequences of operation to optimize system operation. (This will be done after the completion of the project.)

ECM-5 RAS and WAS Pumping Improvements

• Assess visible surfaces within scum pit and RAS wet well. (All surfaces were found to be adequate and will be reused.)
• Develop description of RAS pumps, WAS control valve, flow meters, process instrumentation, piping, valves, scum troughs, and scum pumps. (This has been completed. All four pumps will be replaced.)

ECM-7 & ECM-8 Electrical Upgrades and Backup Power

• Evaluate and develop retrofit solutions for power requirements (hp and voltage) for new motors and loads in proposed ECMs. (This has taken the longest time to complete and is still in motion. The project, as of now will replace the existing MCC1 (Motor Control Center).)
• Size and specify replacement solution for standby generator and transfer switch. (The generator has been chosen, and we are on hold until Air Quality Control approves this installation.) 
• Toni Artho will provide an update to the R & I Committee in March. 

ECM-9 SCADA System

• Develop preliminary process and instrumentation diagrams for coordination with SCADA design
• Develop scope of work for all necessary SCADA upgrades

ECM-12 Sewer Lift Stations (B1 and B4)

• Develop design flows for each lift station based on available plant records, review of upstream land uses, and estimated peaking factors
• Confirm design criteria (flow and head requirements) for submersible pumps at each station
• Confirm size (depth and operating ranges) for wet well
• Evaluate dimensions and visible condition of existing wet well to determine if it can be used or a new wet well should be constructed
• Develop preliminary layout of B1 and B4 for review by District staff
• Develop description of new pumps, valves, access hatches, instrumentation, and appurtenances
• Develop scope of work and 30% design to integrate lift stations into existing SCADA system
• Conduct Feasibility Assessment for four (4) additional Lift Stations