The Thrasher Group, Inc.

Scope Of Work

Long Term Control Plan

We’ve worked continuously during the past years with the City of Bridgeport in a multi-phase project to develop and implement a Long Term Control Plan to correct I&I problems and develop maintenance schedules for their wastewater treatment collection and treatment system.

The original sanitary and storm sewer systems were constructed over many decades. Several interconnections existed. Until 1974, both systems discharged directly into the receiving streams. At that time, a 1.5 MGD wastewater treatment plant and an interceptor system we’ve implemented. The City of Bridgeport and the surrounding area quickly outgrew the plant. The City began a series of projects designed to improve both the treatment facilities as well as the collection system to accommodate growth and to address CSO issues.

Project Phases

1995 – Phase II: The existing 1.5 MGD wastewater treatment plant (WWTP) was replaced with a 3.0 MGD WWTP. The plant has accommodated the growth of Bridgeport and the surrounding areas by providing excellent and reliable treatment.

1997 – Phase III: Three sub-phases: Extensions, lift stations and line and manhole replacements.

1999 – Phase IV: Thrasher investigated suspected trouble areas using video camera inspections, smoke testing and manhole inspections. The reconstruction project included rebuilding and relocating lift station # 7, which increased its capacity to handle large amounts of flows during wet weather. The project also replaced 8,600 linear feet of mains throughout the City greatly reducing system I & I.

2002 – Phase V: Approximately 4,000 linear feet of sanitary sewer mains through the city were replaced. The lines replaced were increased in size so that more flow could be transported.

2007 – Phase VI: Approximately 8,000 LF of force main was constructed and the capacity of two lift stations was increased reducing frequency and volume of four (4) CSO outlets, located near schools and recreational parks.

2010 – Phase VII: This project replaced 3,000 LF of 16” and 20” gravity mains and eliminated a porous sanitary system that had been constructed in and near a creek.

2011 – Phase VII: Collection system improvements focused on further reduction of inflow and infiltration (I&I) and addressed maintenance concerns.

2013 – WWTP Upgrades: Various process upgrades throughout the plant including effluent foam reduction, influent screening, DO measurement and VFD control for existing rotors, and a new sludge press.