(EBPR) Pilot Testing & Design Glendale Street and Northside Wastewater Treatment Facilities

The City of Lakeland owns and operates the McIntosh Power Generation Facility, which currently uses approximately an average of 11 mgd of water for cooling purposes. Effluent currently produced by the City's Glendale Street and Northside WWTFs, approximately 7 mgd and 4 mgd, respectively, is combined and used as cooling water by the McIntosh Facility. However, the McIntosh Facility had experienced cooling tower scaling problems believed to be associated with elevated Phosphorous (P) levels in the City's WWTF effluent stream, which limited the reuse potential of this water. Based on findings of a Feasibility Study Report prepared by Envisors to evaluate physical, chemical, and biological treatment alternatives to reduce effluent P levels, the City chose to implement EBPR process improvements at its WWTF to improve effluent quality, eliminate its cooling tower scaling problem, and maximize the reuse potential of the City's 11.0 mgd effluent stream. Prior to designing and constructing the planned full-scale EBPR process improvements at the Glendale Street WWTF, which has unique process flow characteristics, the City chose to perform pilot testing for design optimization and to verify that the proposed improvements would achieve the City's treatment requirements for reuse purposes. The City contracted with Envisors to design, construct, and operate three scaled pilot treatment systems to simulate various design and operational options. During the six month pilot testing period, Envisors collected several hundred samples and evaluated water quality test result data to evaluate treatment performance at current and ultimate flows and organic loadings for various design options. Envisors prepared a summary report describing project findings and full-scale design improvement recommendations for both the Glendale Street and Northside WWTFs. In February of 2003 the Ridge Chapter of the Florida Engineering Society recognized Envisors' groundbreaking research and design efforts on this Project by bestowing on them its 2002 Project of Outstanding Technical Achievement Award. Also, the results of the pilot test study were published by the Water Environment Research Journal in the September/October 2005 issue, and presented by the Envisors Project Manager at the 2003 WEFTEC Conference in Los Angeles, CA.