WWTP High Rate Treatment System
Lakewood, Ohio
The most significant improvement at the WWTP is the addition of a High Rate Treatment (HRT) facility. The new HRT system will comply with NPDES permit requirements issued by Ohio EPA to address CSO overflows near the plant.
The Lakewood WWTP is an activated sludge wastewater treatment plant designed to treat an average day designed flow of 18 MGD, and the sustained peak primary and secondary treatment capacity for wet-weather flows of 30 MGD.
The most significant improvement at the WWTP is the addition of a High Rate Treatment (HRT) facility. The new HRT system will comply with NPDES permit requirements issued by Ohio EPA to address CSO overflows near the plant. Flow rates to be handled by the wet weather HRT system were estimated using Storm Water Management Model and the design provided initial parameters for the treatment of wet-weather flow.
CT worked with the city to evaluate and select an HRT system by completing a six-week pilot study to assess treatment efficiency, capital and operation and maintenance costs, and constructability economic analysis of Veolia-Kruger’s ACTIFLO® and BIOACTIFLO® processes.
The ACTIFLO process combines two treatment technologies: ballasted flocculation and plate settling. The BIOACTIFLO process combines biological treatment with the ACTIFLO ballasted flocculation high-rate clarification. This was provided by a solids contact basin which was used ahead of the ACTIFLO high-rate clarification.
The full-scale HRT system is located adjacent to the WWTP and sized to handle 35 MGD. During wet-weather events, flows in excess of 30 MGD will be diverted from the WWTP to the HRT facility providing a combined wet-weather treatment capacity of 65 MGD.
Pictured is the effluent connection pipe being constructed from the HRT into the Lakewood Storm Sewer System and then ultimately into Lake Erie. It is very unique to construct a pipe under a river, needing to work with the Army Corps of Engineers and designing for very specific construction techniques.