PROJECT HIGHLIGHTS
One of two Enviroquip MBR Systems the Tribe owns.
DESCRIPTION
The Confederated Tribes of the Chehalis Reservation located in Oakville, WA developed a Master Plan for their reservation that included seven (7) decentralized MBR Systems for wastewater treatment ranging in size from 6,000 gpd to 112,000 gpd. The second, of which, treats wastewater from a housing development. The pre‐ cast concrete package plant was located inside a metal frame building to help the plant blend into the surrounding neighborhood. The existing onsite septic system was left in place as a standby to be used when the single train MBR System was down for cleaning or maintenance. Discharge from the facility is sent to an infiltration basin. For more information on the first MBR plant on this reservation, please see the Chehalis Public Safety Building WWTP case study.
LOCATION
Oakville, WA
IMAGES
PROJECT OVERVIEW
| System Type(s) | Enviroquip ® MPAC® |
|---|---|
| Previous Facility Type | Septic |
| Owner | Confederated Tribes of the Chehalis Reservation |
| Engineer | Brown & Caldwell, Ayres & Associates |
| Contractor | Ayres & Associates |
| Operations | Confederated Tribe of the Chehalis Reservation |
| Delivery Method | Negotiation, Pre-Purchase |
| Time To Retrofit | 19 months |
| Total Installed Project Cost | $549,740 |
PLANT DESIGN INFORMATION
| Fine Screen Type | Bar Screen |
|---|---|
| Aperture or Slot Size | 2 mm |
| Supplemental Aeration Technology | Fine Bubble, Disks |
| MBR Blower Type | Regenerative |
| Solids Management Data | Hauling |
| SCADA System | Wonderware |
| Disinfection Method | Chlorine |
| # Process Stages | 3 |
MBR (MEMBRANE ZONE) DESIGN
| Filtration Mode | Pumped |
|---|---|
| # of Reactors : | 1 |
| Submerged Membrane Unit (SMU) | ES75, KUBOTA® |
| # SMU | 2 |
| Design Flux (MMF) | 11.6 gfd |
| Minimum Temperature | 10°C |
| Peak Factor | 2.0 |
| # of Maintenance Cleans | 2 |
