In accordance to the City of Oregon's Ohio EPA NPDES Permit No. 2PD00035*MD, the City is required to increase the secondary treatment capacity of the WWTP from 24 MGD to 36 MGD to eliminate secondary treatment bypasses and sanitary sewer collection system overflows (SSO's) during wet weather events. In accordance to the Compliance Schedule of the said permit, the project will be constructed in two (2) phases over the next five (5) years.
The Phase 1 project improvements consist of the replacement of two(2) influent screens, replacement of three(3) raw sewage pump motor drives, replacement of two blowers, full replacement of air piping and replacement of air diffusers in the aeration tanks and a dissolved oxygen control system, site restoration, and associated Supervisory Control and Data Acquisition (SCADA) upgrades.
Phase 1 Components:
The two (2) existing 1.5 inch opening influent screens will be replaced with two (2) new 0.50 inch opening influent screens.
Three (3) existing raw sewage pump motor drives (eddy current) will be replaced with new variable frequency drives and new inverter duty motors.
Two of the existing blowers will be replaced with new 12,300 scfm blowers with new controls, including replacement of all air piping ranging in size from 8 inch to 30 inch.
The existing secondary aeration system will be improved with new fine bubble membrane air diffusers and appurtenances along with meters, motorized valves, and instrumentation to allow the dissolved oxygen level to be monitored and controlled continuously. The existing SCADA system will be upgraded for the replacements and improvements noted above.
The Phase 2 project improvements consist of a new final clarifier with associated secondary sludge pumping facilities, aeration tank improvements consisting primarily of replacement of stop plates and slide gates, disinfection improvements consisting of replacement of the chlorine feed and safety equipment, effluent pump replacement and improvements, site restoration, and associated Supervisory Control and Data Acquisition (SCADA) upgrades.
See the below link for more information regarding the WWTP Secondary Treatment Improvements Project and the associated Capital Improvement Charge