Southerly Wastewater Treatment Plant, S71 New Effluent Pump Station and Effluent Conduit
Client: The City of Columbus, Ohio
Due to an Ohio Environmental Protection Agency's Consent Order and the increased demand in the Central Ohio area, the City of Columbus started projects to upgrade the Southerly Wastewater Treatment Plant. This was the first of several projects required to be completed to bring the Southerly Plant into compliance. The design parameters required the Effluent Pump Station facility to have a maximum hydraulic pumping capacity of 330 mgd, expected in the year 2010 at this plant. The structures (EPS and EDC) are designed to have a maximum hydraulic capacity of 440 mgd in 2010.
The Interdisciplinary Approach
The construction of the EPS Facility began in early February 2008. The facility consisted of construction of a 440 mgd Effluent Control Building (ECB), an Effluent Metering Chamber (EMC), Effluent Metering Building (EMB), Effluent Transition Chamber (ETC), Effluent Sampling Building (ESB), Effluent Electrical Building (EEB), Disinfected Effluent Conduit (DEC), Effluent Discharge Conduit (EDC) and the Effluent Discharge Structure (EDS). This EPS facility also included construction of a new flushing water system and other associated processes (chlorination, metering, sampling, etc).
This project required simultaneous construction (excavating, placing concrete, erecting forms for multiple structures, etc.) to meet the rigid project deadlines. A necessity for the project to succeed (on time and on budget) required that a levee be constructed around the main structures to alleviate flooding from the nearby Scioto River. This protected the project on more than one occasion during construction.
Chester Engineers' Construction Management staff, consisting of a Construction Manager and a Field Project Representative, were an integral part of the Construction Management Team (CMT) responsible for the scheduling, management, and quality control during construction of the New Effluent Pump Station (EPS) Facility.
The Sustainable Result
This project (referred to as S71), was the first of several projects required to bring the Southerly Plant into compliance with the EPA's Consent Order. Each subsequent project was, essentially, on the 'coat tails' of this project. This meant that if S71 missed milestones, or was not on schedule, then S72 and S73 could not even begin work. This would result in major cost overruns, back charges by the Contractors on S72 and S73 and liquidated damages assessed to the S71 Contractor. To enhance the chances of S71 being completed on schedule, the Professional Program Management team and the Owner, with critical input from the CMT, worked with the General Contractor (GC) to accelerate portions of the work to ensure that critical milestones were met. This required excellent communications between the Owner, Design Engineer, CMT and the GC to expedite submittal reviews, work orders and inspection services to assist in achieving this lofty goal. The S71 Project and commissioning of the equipment, flushing water system, flow monitoring, dechlorination and sampling processes was completed ahead of schedule.