PROJECT HIGHLIGHTS
Operational
Domestic WW, Greenfield
Permit(s); Class 4 Injection well
10/NA/0.2 (TN/TP/Turbidity)
Municipal -> Infiltration System
MMF Capacity: 0.035 MGD
$121/gal
1.5 FTE (Full‐Time Employee)

MBR was the best available technology
DESCRIPTION
The Skokomish Indian Tribe decided to construct three new wastewater reclamation facilities (WRF) in association with Mason County and the Mason County PUD No. 1, the “Tri‐Party Consortium.” The Skokomish Indian Tribe decided to employ membrane bioreactor (MBR) technology to provide a high level of wastewater treatment. As part of a statewide initiative to decrease pollution being discharged into Puget Sound and Hood Canal, the Skokomish Indian Tribe developed wastewater collection, treatment and disposal systems in areas that currently rely on on‐site sewage systems.
LOCATION
Potlach WRF, WA
IMAGES

PROJECT OVERVIEW
System Type(s) | OVIVO MBR |
---|---|
Previous Facility Type | Septic w/wet wells to drain fields |
Owner | Skokomish Nation |
Engineer | Gray & Osborne |
Contractor | McClure & Sons |
Operations | Water & Wastewater Services |
Delivery Method | Pre-Selection, Pre-Purchase |
Time To Retrofit | 12 months |
Total Installed Project Cost | $4,256,538 |
PLANT DESIGN INFORMATION
Fine Screen Type | Drum Screen |
---|---|
Aperture or Slot Size | 2 mm |
Supplemental Aeration Technology | Fine Bubble, Disks |
MBR Blower Type | Positive Displacement |
Solids Management Data | Hauling |
SCADA System | Wonderware |
Disinfection Method | UV |
# Process Stages | 3 |
MBR (MEMBRANE ZONE) DESIGN
Filtration Mode | Pumped |
---|---|
# of Reactors : | 2 |
Submerged Membrane Unit (SMU) | RM150 |
# SMU | 4 |
Design Flux (MMF) | 5.88 gfd |
Minimum Temperature | 10°C |
Peak Factor | 2 |
# of Maintenance Cleans | 4 |