Hite Creek Water Quality Treatment Center Expansion
Magna Engineers is providing electrical, instrumentation, HVAC, and plumbing designs for this $24M major plant expansion. The project includes replacement of screening equipment, aeration system upgrades including new blowers, aeration tanks, and nitrate pump station, new tertiary filter system, replacement of existing UV system, sludge holding improvements including new blowers and holding tank upgrades, centrate equalization tank, dewatering facility including centrifuge, sludge pumping, polymer system, and sludge loading station. The project also includes improvements to site lighting and demolition of existing unused facilities.
The electrical design includes the replacement of a single end feed unit substation with a double-ended substation with 12,470V primary, 480/277V, and 3000A main-tie-main bussing. The power system also includes a new 1250 KW standby diesel generator. Double-ended feeders are provided to main-tie-main motor control centers at the aeration building and dewatering building. The existing influent pump station is being backfed from each side of the main switchgear tie through an automatic transfer switch. Additional single ended feeders are provided to the tertiary filter building and sludge holding blower building.
Instrumentation includes dissolved oxygen, ORP, and pressure measurement for aeration system control, flow and level measurement for centrate equalization control, level and pressure measurment for sludge holding tank controls, level measurement and gate controls for tertiary filters, and flow measurement, control of gates and valves, and various other instrumentation for the dewatering system. Multiple programmable logic controller panels will be added to the existing plant Supervisory Control and Data Acquisition System which communicates over fiber optic redundant ring. Programming of PLC’s and IFix HMI software is included.
HVAC design includes heating, ventilation and air conditioning for the new tertiary filter building, the new dewatering building, and the renovation of the existing aeration blower building. The dewatering building includes an energy recovery unit which is connected in series with the carbon odor control system. Six air changes per hour are provided in the dewatering building for operator safety and reduction of the hazardous area classification.