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Washington SBR plant: back in permit compliance
At an overloaded resort community plant, we cut SVI from 400 to below 150, met summer permit limits for the first time in five years, and added 17% capacity.
Results at a glance
400 to below 150SVI, so solids stayed in the plant
First time in 5 yearssummer permit limits met
17%added capacity
8 yearsupgrade delayed, an estimated $500,000 saved
The project
What we did
We provided support services for an overloaded sequencing batch reactor (SBR) plant serving a resort community in Washington. Our support is listed at right.
Driven by regulatory pressure, plant modifications cut the sludge volume index (SVI) from 400 to below 150, so solids stayed in the plant and permit compliance followed.
We also developed startup training for the SBR plant and managed the O&M manual, writing the secondary treatment chapter.
Our support covered
- Management and operational assistance
- Training
- Design review
- Laboratory evaluation
- Maintenance assistance
Before and after
Plant results
| Measure | Before | After |
|---|---|---|
| Sludge volume index (SVI) | 400 | Below 150 |
| Summer permit limits | Not met in the five years before | Met for the first time in five years |
| Plant capacity | Overloaded | 17% added capacity |
What it meant for the utility
- Solids stayed in the plant
- Permit compliance followed
- 17% added capacity
- Design and upgrade delayed for eight years
- An estimated $500,000 saved
- Startup training and an O&M manual for the plant