"The Vital Back Cove Ecosystem will be Protected from Pollution for Future Generations to Come.”
WOODFORD STREET SEWER SEPARATION PROJECT
The City of Portland, Maine is known for its booming arts and culture scene, historical seaport and famous seaside beauty. But for years both residents and wildlife of Portland have been plagued by an increased amount of Combined Sewer Overflows (CSO) along the shore of the Back Cove estuary basin. Heavy rainfall events have spurred a tremendous undertaking by the combined sewer system to transport stormwater and sewage to the East End Wastewater Treatment Plant, ultimately failing. This chronic issue has garnered increased concern from city officials for the health and well being of Portland residents, local wildlife and flora, as well as the
entire Back Cove ecosystem.
Therefore, the City of Portland commissioned one of several contracts to remedy the issue by separating the combined sewer system into a dedicated sanitary sewer and storm drain. D & C Construction and engineering firm Sebago Technics were contracted to build the system along Woodford Street. The project plans included a new storm drain outfall for Back Cove at the intersection of Vannah Ave and Baxter Blvd and the installation of a Nutrient Separating Baffle Box® (NSBB) hydrodynamic separator along with sidewalks. The Woodford Street Sewer Separation Project ensures improved water quality by minimizing CSO’s and being proactive to filter runoff flowing into Back Cove via the NSBB. Overall, human and wildlife health will improve upon completion and the vital Back Cove ecosystem will be protected from pollution for years to come.
Revitalizing the Ground Work
The Woodford Street Sewer Separation Project broke ground on March, 27 2017. The city’s contractor, D & C Construction, started its installation of a new storm drain at the
intersection of Woodford Street and Clifton Street. Simultaneously beginning on March, 28 2017, crews started work on Woodford Street between Forrest Ave and Vannah Ave continuing for several months. During this time D & C Construction installed new sewer and storm drain lines in addition to the installation of a new 84” storm drain outfall into Back Cove estuary at the intersection of Vannah Ave and Baxter Blvd. The new storm drain outfall includes a riprap apron along with a backflow prevention system to stop high tide events from entering the system, potentially damaging the Woodford Street NSBB stormwater treatment unit.
Woodford Street NSBB™ will Avert Potential Pollution
Direct treatment of the stormwater flowing in the Woodford Street line is now filtered via an NSBB which was installed on July, 7 2017. The NSBB, developed by Suntree Technologies Inc®, an Oldcastle Infrastructure™ company, is a hydrodynamic separator specializing in online sediment capture without the typical associated headloss and sediment scouring. It’s patented lidded screens prevent nutrient leaching and static water from turning septic from trash and debris. It also includes a floating skimmer unit to prevent debris from passing through the vault during high flows and a StormBoom™ that absorbs hydrocarbons and oils via an absorption media.
Prior to delivery, Suntree Technologies Inc Personnel were on site at a local precast facility to install the NSBB internal components including the deflectors and HydroSlide®. The HydroSlide is an optional servicing system for the NSBB to facilitate sediment removal. The system reduces servicing time by using a vacuum truck to spray water through its pipes loosening sediment and easily vacuuming it away. The system does not require confined space entry, effectively saving the city a great deal in upkeep costs. The delivery and installation of the vault structure took only a day to complete as a joint effort between D & C Construction, Sebago Technics, and Suntree Technologies. The Woodford Street NSBB vastly improves the water quality of runoff flowing in the system and prevents any pollution of trash, sediment and hydrocarbons from reaching Back Cove. Portland’s investment in water quality and commitment to reducing CSO’s will result in pollution decline and an overall healthier community.
© 2018 Suntree Technologies Inc