Keller Associates completed the planning, design, and construction inspection for a unique oxidation ditch wastewater treatment facility for the City of Rigby, Idaho. The City of Rigby has high groundwater and thus infiltration during summer months.  This causes the flow at the treatment plant to increase from 0.3 MGD to as much as 2.5 MGD.  The solution was an oxidation ditch process with enlarged clarifiers and filters.

Services Included:

• Planning, concept development, design and construction engineering for a new treatment plant with capacity of 0.65 MGD for BOD removal and hydraulic capacity of 2.5 MGD to handle high infiltration during the summer irrigation season
• This facility replaces the City’s existing lagoon system and is able to meet 85% BOD/TSS reduction during summer I/I season
• The WWTP includes headworks, with screen and grit removal; two oxidation ditches; two secondary clarifiers; two cloth filters; UV disinfection; and solids handling, including aerated digesters and belt