Lihue Puhi WWTP Capital Improvements

This project will be implemented in a way that ensures the plant remains fully functional throughout the construction process. The following facilities will be modified: Influent Facilities Upgrade: Existing magnetic flow meter will be removed and replaced with trapezoidal flume and ultrasonic level element in a new reinforced concrete channel, for improved influent flow monitoring. Two (2) new Huber Rotamat® Ro9 auger screens will be installed in the existing concrete channels to replace aging auger screen and manual bar screen for full redundancy. Third reinforced concrete channel will be constructed to provide by-pass flow capabilities. New aluminum grating and handrails will replace aging fiberglass grating and railing. Blower System Upgrade: Three (3) existing aging rotary lobe blowers will be replaced with two (2) new variable speed rotary screw positive displacement Kaeser® blowers in sound attenuated enclosures. These blowers use advance technology that results in higher operating efficiency, lower energy consumption and noise levels and reduction in the footprint. The two blowers will provide full redundancy of air supply for the treatment process. Human-Machine Interface (HMI) controller will be provided to allow operators to adjust blower output based on daily flow variations and treatment process air demand. Aeration Header Replacement: The existing aging aeration header and distribution valves will be replaced with new to ensure continuous reliable operation. Tertiary Filter Improvements: Existing aging up flow sand filters will be removed and two (2) trains of new Aqua Aerobics® cloth disc filters and associated backwash pumps and controls will be installed in the unused filter tank compartments. Existing unused filter tank compartments will be retrofitted to accommodate two disk filter trains. Disk filters operate at higher efficiency and take smaller footprint than the sand filters, and this upgrade will result in lower energy consumption and full redundancy of the process. New steel roof over the filter tanks will be installed for UV protection, and new aluminum grating and handrails for safety. SCADA System Implementation: New Supervisory Control and Data Acquisition (SCADA) system will be implemented to enable remote plant monitoring and control capabilities that will improve plant resilience.