Contract 15-2: Wastewater Treatment Plant Upgrades
Designed by AECOM, Inc.

In July of 2020, Methuen Construction Company, Inc. was awarded the contract for this project. The scope included 18 upgrade projects around the treatment plant. Some of the most significant upgrades were the replacement of the boilers in the Process Building, replacement of the High Head Effluent Pump VFDs, replacement of the air conditioning unit for the Effluent Pump Station, replacement and painting of plant water and sprinkler piping in the Primary Pump Room and tunnels, and replacement of the hydrogen peroxide bulk storage tanks. This project improved our plant’s overall reliability and condition by replacing critical process equipment that reached the end of it’s service life.

New Boiler Installed December 30, 2020 © SESD
New Boiler Installed December 30, 2020 © SESD
Install Team for New Boiler Room #4 © SESD
Install Team for New Boiler Room #4 © SESD

In this picture, you can see the mechanical exterior of the new Variable Frequency Drive, or VFD. A VFD is an electrical device that controls the speed of an electric motor, such as the ones used at our wastewater treatment plant, by varying it's input voltage.New Variable Frequency Drive (VFD) © SESD

Contract 20-1: Danvers Siphon Rehabilitation
Designed by CDM Smith

To ensure continuous system improvements, the District initiated a condition assessment in 2018 which determined that this siphon rehabilitation project was required. Corrosion caused by the surrounding soils and salt water environment created concern that without this rehabilitation, untreated sewage could enter the Porter River, impacting the environmental ecosystem of the river, creating public health concerns, and impacting recreational uses of the river.

© CDM Smith
© CDM Smith

The four siphons are located under the Porter River in the town of Danvers, MA: one ductile iron triple-barrel siphon constructed in the 1970s at River Drive; the other a cast iron single-barrel siphon constructed in the 1920s at River Street. This project used Cured-In-Place Pipe Lining (CIPPL) to fully restore the structural integrity of the pipelines, removing the risk of a pipe failure and potential sewage exfiltration, and providing a minimum 50-year extension of the design life. The use of CIPPL has a low environmental impact and does not require major construction or disturbance to the adjacent residents and environment.

The project was bid and awarded to Michels Pipeline Service to complete the work. This was completed December 2021. This project was funded by the Commonwealth of Massachusetts State Revolving Fund (SRF) loan program.

Contract 20-1 Team prepares siphon liner for final inversion processContract 20-1 Siphon liner inversion complete and cooling before reinstating flowContract 20-1 Michels' inversion-installation team completed 955-feet of 24-inch siphon-barrel lining

Contract 11-3: Combined Heat & Power

The Combined Heat and Power (CHP) unit at the District has been operating since January of 2020. This 1,450 kilowatt generator burns natural gas. It currently supplies approximately 2/3 of the District’s electrical power at the plant.

Combined Heat & Power Unit © SESD
Combined Heat & Power Unit © SESD

We now recover heat from the motor and engine exhaust and are using that heat to reduce our boiler use. During the summer months the CHP generates enough heat to operate all three odor control coils!

Diagram of SESD CHP Unit
Diagram of SESD CHP Unit
Construction completed in 2020 © SESD
Construction completed in 2020 © SESD

The CHP system operates 24 hours a day, all year long. It is estimated that the CHP unit will save the District more than $600,000 per year in energy costs. This savings will be used to increase the District’s annual capital improvement program and fund additional capital upgrade projects.

District Contract No. 16-2: Beverly Pump Station Bar Rack Replacement Project
Designed by Wright-Pierce
30-year-old Slide Gate at Beverly Pump Station © SESD
30-year-old Slide Gate at Beverly Pump Station © SESD

Contract 16-2 was completed by Weston and Sampson CMR, Inc. in April 2021. The project entailed the replacement of the existing Bar Rack Number 1 at the Beverly Pump Station. The Station is used to pump wastewater from Beverly, MA to the South Essex Sewerage District treatment plant in Salem, MA.

New Bar Screen Spacing © SESD
New Bar Screen Spacing © SESD
New Bar Rack, Screen and Wash Press © SESD
New Bar Rack, Screen and Wash Press © SESD

The District reduced the bar spacing on the rack to 3/8 inch to remove more solids and “flushable” wipes that cause lots of ragging issues.

Because this tighter bar spacing will result in an increased volume of screenings that are captured at the station, the District also installed a Wash Press which will rinse and compact the screenings before they go into a dumpster. This project also included a new Control Panel for the Pump Station, as well as a replacement roof.