HISTORY

In 2006, the Town hired Vollmer Associates, LLP to design a sanitary pump station and sewer design for the proposed Legacy Place development that was being permitted for construction around that time. The design consisted of a pumping station to be constructed in an easement area located between Legacy Place, Avalon Station 250 and Jefferson at Dedham Station along with approximately 2,500 linear feet of 6” Ductile Iron force main and approximately 800 linear feet of 12” PVC gravity main. The design of the pump station was based upon assumed flows to be generated by the proposed Legacy Place development along with flows from the existing properties already connected to the existing sewer system that would need to be redirected to the proposed pump station. The pump station and sewer was installed in 2008.

In 2013, the Town hired Weston & Sampson to perform an evaluation/study on the pump station to assess its performance and efficiency since its installation and operation starting in 2008. Their evaluation concluded that the pump station appeared to be near or at capacity and made recommendations to improve its overall efficiency consisting of installing Variable Frequency Drives (VFD) on the existing pumps, replacing the current level control system with a new system and other small improvements. They also concluded that in order to handle significant increases in daily flows, larger and higher horsepower pumps would be required and that with larger pumps the existing 6 inch force main would have to be replaced with a larger force main to handle the higher velocities from the larger pumps.

In early 2018, the Engineering Department was contacted by a few engineering companies and developers regarding potential new developments in the area of Legacy Place. These potential developments would have to discharge their sanitary flows to the pump station. Knowing the potential of new developments coupled with the 2013 pump station evaluation concluding that the pump station would likely not be able to handle increased flow, we hired Weston & Sampson to conduct another pump station evaluation/study to assess its condition after 10 years of service and its ability to handle new flows.

Based upon their evaluation/study, they determined that the pump station was handling flows almost 2 times greater than what it was designed for and as a result, the life of the system has been reduced by approximately half. It was stated that any additional flow would only reduce the already shortened useful life of the system and increase the chances of failure. It was recommended that the pump station not handle any additional flow without a significant upgrade to the system. Weston & Sampson evaluated what it would take to handle flows from potential new developments along with change in uses at existing developments to come up with recommendations to upgrade the pump station and sewer system. The major recommendations included the following:

• Increasing the size of the pumps to adequately and efficiently handle the current flows and future flows.
• Increase the size of the existing force main from 6” to 10” to be able to handle future flows.
• Upgrade approximately 2,000 linear feet of 12” gravity sewer main to an 18” gravity sewer main. With the increase in flow, the current size of the 12” gravity main which transports the discharge from the pump station discharge to the 21” interceptor located on Fairbanks Road would be insufficient resulting in potential sanitary sewer overflows.

FUNDING

At the Fall Town Meeting held in November of 2018, Town meeting voted to approve $270,000 from the Sewer Enterprise Fund for the design. At the Spring Town Meeting held in May of 2019, Town Meeting voted to approve $3,200,000 for construction. 

DESCRIPTION OF IMPROVEMENTS

• Installation of approximately 4,900 linear feet of 10-inch ductile iron force main.
• Installation of 3 force main cleanout manholes
• Installation of an air release valve.
• Replacement of existing wet well pumps with 2 new submersible pumps capable of pumping 1,300 GPM
• Retain existing 6-inch ductile iron force main as emergency by-pass.

NOTICE TO PROCEED

The project was put out to bid on 3/18/20 with a bid opening held on 4/9/20. The bid was awarded to RJV Construction Corp. with a low bid of $1,646,302.85. The bid was reviewed and a Notice To Proceed was given to RJV to start construction on 05/04/20. The estimated project cost including construction, police details, resident engineering and contingency is $2,250,000.

TIMELINE

The contractor has 180 days from the Notice To Proceed to complete the project. The contractor is scheduled to break ground near the end of May. 

DOWNLOADS

• Project Limits Map
• Project Plans

CONTACT INFORMATION

Please feel free to contact the Director of Engineering, Jason Mammone, P.E. at 781-751-9350 or jmammone@dedham-ma.gov with any questions or concerns.