Water Street Sewer Interceptor Replacement Project
The Town of Plymouth has entered into a construction contract with Northern Construction Service, LLC of Palmer, MA, to complete the Water Street Sewer Interceptor Replacement Project.
The existing Water Street Sewer Interceptor is a 30-inch diameter reinforced concrete (RCP) sewer interceptor that was originally constructed in 1969 and serves as the primary pipeline for conveying wastewater flows from downtown Plymouth to the Water Street Pump Station. The interceptor is approximately 1,400 linear feet and is located within Plymouth Harbor.
In 2021, the Town appropriated funds for the design and construction of the Water Street Sewer Interceptor Replacement project through the American Rescue Plan Act (ARPA) funding program. The Town retained Environmental Partners in the Fall of 2021 to complete the design and permitting for the interceptor replacement work. The replacement of the existing 30-inch RCP interceptor with a deep open-cut combined interceptor and gravity sewer on Water Street was selected as the most cost-effective solution that would best adhere to the Town’s desired construction schedule of completing all work by the Summer of 2023.Construction is anticipated to begin on December 1, 2022.
A public informational meeting was held on November 10, 2022 where Town staff and Environmental Partners provided an overview of the project, including anticipated construction schedule, and possible impact on the area. A link to the presentation can be found here.
CONSTRUCTION UPDATES
Construction began the week of December 8, starting at the rotary on Water Street. During construction, please expect to be inconvenienced by traffic delays, detours, uneven/settling trenches, parking restrictions, and elevated noise levels. Please follow the detour signs that are installed along the project area. Traffic detours will be modified as construction progresses towards the State Pier. Please see the attached map for the first detour pattern that is anticipated to be in place starting December 12, 2022.
Week Ending March 31, 2023
Construction activities for this week consisted of the following:
- On Monday (3/27), Northern installed two new 12” gate valves and replaced a 12” DI tee on the existing 12-inch DI water main located near the intersection of Chilton Street and Water Street. The area was backfilled following the completion of this work.
- On Tuesday (3/28) and Wednesday (3/29), Northern worked on general site cleanup and rearrangement of their laydown area inside Memorial Hall parking lot.
- On Thursday (3/30), Northern began prepping the roadway to install casings for additional deep wells along the Water Street interceptor alignment. Drilling of additional deep wells along Water Street is tentatively scheduled for Friday (3/31) and Saturday (4/1), which will be performed by Northern’s well driller (McQuilkin Dewatering).
- Traffic continued to be detoured per the construction signage and the message boards provided for the project.
- Site cleanup took place at the end of each day.
Northern will resume work on-site next week (week of 4/3/2023) and the following work activities are anticipated to occur:
- Northern will have their well driller on-site next week to continue with the drilling of additional deep wells along Water Street.
- Northern will have their geotechnical engineer (GeoEngineers) on-site on Monday (4/3), to perform pump drawdown tests to confirm the performance of the additional deep wells. The results of the pump drawdown tests will determine how Northern will proceed with work activities for the remainder of the week.
Week Ending March 24, 2023
Construction activities for this week consisted of the following:
- On Monday (3/20), Northern continued prepping the subgrade for the upcoming pavement restoration along Water Street (from rotary towards Chilton Street).
- On Tuesday (3/21), Northern saw-cut the pavement and marked the roadway where an existing transite drain line runs above the existing 12-inch DI water main located near the intersection of Chilton Street and Water Street. The transite pipe was removed and disposed on Thursday (3/23) in order to complete the water main tee/valve replacement work at this intersection. The area was backfilled and paved following completion of this work.
- On Wednesday (3/22), Northern installed the frame and cover on the first new sewer manhole on Water Street (near rotary). The crew also placed a 7” asphalt trench patch for the previously completed water main work near Howland Street and Brewster Street.
- Traffic continued to be detoured per the construction signage and the message boards provided for the project.
- Site cleanup took place at the end of each day.
Northern will resume work on-site next week (week of 3/27/2023) and the following work activities are anticipated to occur:
- Digging of test pits between Howland Street and Brewster Street to confirm the depth of sewer service laterals in the area.
- Drilling of additional test borings along Water Street sewer interceptor alignment (date TBD).
- Installation of casings for additional deep wells to be installed along Water Street sewer interceptor alignment (scheduled for Wednesday, 3/29, and Thursday, 3/30).
- Drilling of additional deep wells along Water Street sewer interceptor alignment (scheduled for Friday, 3/31, and Saturday, 4/1).
Week Ending March 17, 2023
Construction activities for this week consisted of the following:
- Northern continued driving steel sheeting along Water Street for the new gravity sewer interceptor and continued to prep the subgrade for pavement restoration. Due to inclement weather, no activities occurred on Tuesday (3/14).
- Northern prepped the existing 12” DI water main on Water Street (near Memorial Drive) to install a new 12” insertion valve. The valve was installed on Wednesday (3/15).
- Northern prepped the existing 12” DI water main on Water Street (near Brewster Street and Howland Street) to install new 12” gate valves and 12” DI tees. The valve/tee near Brewster Street was installed on Thursday (3/16). The valve/tee near Howland Street is being installed on Friday (3/17).
- Northerns’ drilling contractor (New England Boring Contractors) was on-site on Wednesday (3/15) and Thursday (3/16) to drill three test borings (two near intersection of Water Street and Chilton Street; one near intersection of Water Street and Howland Street). Northerns’ geotechnical engineer (GeoEngineers) was on-site to log the test borings.
- Traffic continued to be detoured per the construction signage and the message boards provided for the project.
- Site cleanup took place at the end of each day.
Northern will resume work on-site next week (week of 3/20/2023) and the following work activities are anticipated to occur:
- Continue installation of 30” gravity sewer interceptor along Water Street towards Chilton Street.
- Installation of sewer manhole at intersection of Water Street and Chilton Street.
- Installation of gate valve / DI tee at intersection of Water Street and Chilton Street along 12” water main on Water Street.
- Restoration of pavement between 122 Water Street and Water Street rotary, install pavement marking, and restore traffic back to two-lane travel in this section.
Week Ending March 10, 2023
Construction activities for this week consisted of the following:
- Northern continued driving steel sheeting and installing gravity sewer interceptor piping along Water Street on Monday (3/6). Northern excavated, installed, and backfilled approximately 14 linear feet of the 30” PVC gravity sewer interceptor along Water Street toward Chilton Street.
- On Tuesday (3/7) morning, dewatering challenges were encountered in the excavation, and silty water was discharged into the harbor as a result. Northern installed a second frac tank and perimeter controls and a turbidity curtain at the outfall near the restroom building on the State Pier to help contain and address this sedimentation release.
- On Tuesday morning, settlement was observed at nearby businesses and structures along Water Street. Work on the sewer interceptor was temporarily put on-hold until these concerns have been addressed. A portion of Water Street (between Chilton Street and the Rotary) and all of Chilton Street was closed to vehicular traffic.
- The remainder of the work activities by Northern this week include re-establishing well points along the interceptor alignment, prepping the site for paving, and general site cleanup.
Work on the sewer interceptor installation is currently on-hold until further assessment of the groundwater conditions is completed by the contractor’s consultant. In the meanwhile, the contractor will focus on preparing the subgrade for the roadway over the previously installed pipeline. Additional work will include drilling and installation of piezometers to help assess the issues with dewatering.
Week Ending March 3, 2023
Construction activities for this week consisted of the following:
- Northern continued removal of bracing sheets along the new sewer interceptor alignment on Water Street this past week.
- Northern repaired leaks inside the first manhole near Memorial Drive, cleaned the manhole, and started building the manhole’s bench and invert. Additionally, Northern installed a temporary walk-through for pedestrian traffic between Memorial Drive and Chilton Street.
- Northern placed a 4” asphalt temporary trench patch for the water main work performed on Water Street between Memorial Drive and Chilton Street.
- Traffic continued to be detoured per the construction signage and the message boards provided for the project.
- Site cleanup took place at the end of each day.
Northern will resume work on-site next week (week of 3/6/2023) and the following work activities are anticipated to occur:
- Northern will continue daily movement and vibration monitoring surveys.
- Northern to continue installation of earth support and work towards Chilton Street.
- Northern will continue excavation and sewer interceptor piping installation along Water Street toward the second manhole near Chilton Street.
- Northern to install second manhole near Chilton Street.
- Trench backfilling and removal of earth support in previously completed areas.
Week Ending February 24, 2023
Construction activities for this week consisted of the following:
- There were no activities on Monday (2/20), in observance of Presidents’ Day.
- Northern continued removal of bracing sheets along the new sewer interceptor alignment and relocated equipment down Water Street for the project’s next phase.
- On Tuesday (2/21), Northern found and repaired a water main leak at the ductile iron tee near the intersection of Water Street and Memorial Drive. The Plymouth Water Department was contacted to isolate the damaged portion of the main.
- On Wednesday (2/22) and Thursday (2/23), Northern continued the replacement of the drainage piping and catch basins on Water Street.
- Northern also re-stripped the roadway to reflect the two-way traffic on the south side of Water Street as per the updated Traffic Management Plan (Water Street Stage 2B). Additionally, Northern repaired the water service line for the Plymouth Visitor Center and restored the electrical connection for the light pole at the Plymouth Visitor Center.
- Traffic continued to be detoured per the construction signage and the message boards provided for the project.
- Site cleanup took place at the end of each day.
Northern will resume work on-site next week (week of 2/27/2023) and the following work activities are anticipated to occur:
- Northern will continue daily movement and vibration monitoring surveys
- Northern to continue installation of earth support and work towards Chilton Street
- Northern to continue to excavate and install sewer interceptor piping along Water Street toward the second manhole near Chilton Street
- Northern to complete replacement of drainage pipe and drainage structures along Water Street
Week Ending February 17, 2023
Construction activities for this week consisted of the following:
- Northern continued removal of bracing sheets along the new sewer interceptor alignment on Water Street.
- On Monday (2/13), a sedimentation release was detected near the drainage outfall at Town Wharf going into Plymouth Harbor. The Plymouth Conservation Commission was notified of this event and directed Northern to install a turbidity curtain to contain this sedimentation release. The release appeared to be as a result of two water main leaks found on Water Street (one on the water service for Mamma Mia’s and one along the 12-inch DI water main near the Plymouth Visitors Center).
- On Tuesday (2/14), Northern repaired two additional water main leaks (one near the hydrant near the Plymouth Visitors Center and one on the water service for Ziggy’s). The hydrant in front of the Plymouth Visitors Center was also repaired.
- On Wednesday (2/15), Northern repaired an additional water main leak encountered near the Plymouth Visitors Center. The frac tank and associated equipment were moved further down Water Street for the project’s next phase. Northern added weights to the turbidity curtain at the direction of the Plymouth Conservation Commission.
- On Thursday (2/16), Northern began the replacement of the drainage piping and catch basins on Water Street (between Memorial Drive and Chilton Street).
- Traffic continued to be detoured per the construction signage and the message boards provided for the project.
- Site cleanup took place at the end of each day.
Northern will resume work on-site next week (week of 2/20/2023) and the following work activities are anticipated to occur:
- No work activities will be performed on Monday, 2/20/2023 in observance of Presidents' Day.
- Northern will begin expanding the work zone beyond Chilton Street to the crosswalk across from Isaac's. Northern will begin re-striping the roadway up to Howland Street for traffic control purposes.
- Northern will continue daily movement and vibration monitoring surveys.
- Northern will resume installation of earth support and work towards Chilton Street.
- Northern will continue to excavate and install sewer interceptor piping from the first manhole toward Chilton Street and beyond Chilton Street towards the second manhole.
- Northern to complete reconstruction of drainage pipe and structures.
- Northern to continue restoration of streets between South Park Avenue and Memorial Drive.
Week Ending February 10, 2023
Construction activities for this week consisted of the following:
- Northern Construction Service continued excavating and installing the 30” PVC gravity sewer interceptor along Water Street toward Chilton Street. Approximately 102 linear feet of pipe were installed this past week. Pipe joints were sealed prior to backfilling and compacting the trench for the sewer interceptor.
- Northern continued removal of bracing sheets along the alignment on Water Street.
- The dewatering pumps powered down on Sunday (2/5/23) due to an issue with the dewatering pump generators. On Monday (2/6/23), Northern spent the day dewatering the trench along Water Street and replaced a damaged section of 30” PVC with a new section of 30” PVC before continuing work activities.
- On Wednesday (2/9/23), Northern removed the wellpoint header pipe along Water Street from Station 01+00 to Station 02+50.
- Traffic continued to be detoured per the construction signage and the message boards provided for the project.
- Site cleanup took place at the end of each day.
Northern will resume work on-site next week (week of 2/13/2023) and the following work activities are anticipated to occur:
- Northern will continue daily movement and vibration monitoring surveys.
- Continue to excavate and install sewer interceptor piping from the first manhole toward Chilton Street and beyond Chilton Street towards the second manhole.
- Continue installation of earth support, working towards Chilton Street and the second manhole.
- Trench backfilling and removal of earth support in previously completed areas.
- Continue reconstruction of drainage pipes and structures.
Week Ending February 3, 2023
Construction activities for this week consisted of the following:
- Northern Construction Service continued excavating and installing the 30” PVC gravity sewer interceptor along Water Street toward Chilton Street.
- Timber lagging removal around utilities in the trench along Water Street.
- Trench backfilling and material compaction.
- On Tuesday (1/31/23), a significant leak was observed while removing timber lagging near the adjacent water main. The Plymouth Water Department was contacted to isolate the damaged portion of the main. After the leak was contained, the trench was dewatered, and the water main was repaired.
- On Wednesday (2/1/23), the crew worked on dewatering four feet of water located between station 03+00 and station 01+00 along Water Street.
- Northern installed two manhole risers and top section to complete buildout of SMH-06.
- Replacement of a hydrant gate box that was removed during the break.
- Jet cleaned the newly installed sewer interceptor to remove debris resulting from the break that occurred on Wednesday (2/1/23).
- Traffic continued to be detoured per the construction signage and the message boards provided for the project.
- Site cleanup took place at the end of each day.
Northern will resume work on-site next week (week of 2/6/2023) and the following work activities are anticipated to occur:
- Northern will continue daily movement and vibration monitoring surveys.
- Continue to excavate and install sewer interceptor piping from the first manhole (SMH-06) toward Chilton Street.
- Continue installation of earth support, working towards Chilton Street and the second manhole (SMH-05A).
- Trench backfilling and removal of earth support in previously completed areas.
- Begin reconstruction of drainage pipes and structures.
Week Ending January 27, 2023
Construction activities for this week consisted of the following:
- Northern continued driving steel sheeting along Water Street.
- Excavation and installation of 30” PVC gravity sewer interceptor along Water Street toward Chilton Street.
- Timber lagging installation around utilities in the trench along Water Street.
- Trench backfilling and material compaction.
- Installation of safety railing along steel sheeting.
- Fabrication of steel beams for trench shoring.
- Removal of existing drainage manhole and drainage pipes.
- Excavation and installation of first sewer manhole.
- Placing of “No parking sign” barrels on Chilton Street and installation of detour sign at Brewster Street intersection.
- The deep dewatering wells continue to pump groundwater 24 hours a day, seven days a week. The sump pump powered down over the weekend. Therefore, Monday morning (01/23/23) was spent dewatering the trench.
- Traffic continued to be detoured per the construction signage and the message boards provided for the project.
- Site cleanup took place at the end of each day.
Northern will resume work on-site next week (week of 1/30/2023) and the following work activities are anticipated to occur:
- Northern will continue daily movement and vibration monitoring surveys.
- Continue to excavate and install sewer interceptor piping from the first manhole toward Chilton Street.
- Continue installation of earth support, working towards Chilton Street and the second manhole.
- Trench backfilling and removal of earth support in previously completed areas.backfilling
- Reconstruction of drainage pipes and structures.
- It is anticipated that groundwater will be under control with the deep wells, and additional sumps will handle any water encountered in the trench during the excavations. The contractor will re-evaluate and install as required if a vacuum pump system is needed.
Week Ending January 20, 2023
Construction activities for this week consisted of the following:
- Snow and ice cleanup on the site due to the weekend's winter storm.
- Northern continued driving steel sheeting using a hydraulic hammer within the excavated pavement along the first 300 feet of the interceptor alignment.
- Excavation of trench down to the existing 30" sewer main.
- Placing 3/4" crushed stone
- Installation of a 30" mechanical joint between existing and proposed sewer mains.
- Deep dewatering wells continue to pump groundwater 24 hours a da, seven days a week. Discharge is going through frac tanks.
- Traffic detoured per the construction signage and message boards provided for the project.
- Site cleanup at the end of each day.
Northern will resume work on-site next week (week of 1/23/2023) and the following work activities are anticipated to occur:
- Northern Construction Company will continue the daily movement and vibration monitoring surveys.
- Excavation and piping installation from the point of connection to the first sewer manhole.
- Installation of the first manhole.
- Continue installation of earth support, working towards Chilton Street.
- Continue pipe installation, connection to the first manhole, and continue along Water Street, working toward Chilton Street.
- Start removal of earth support where the trench has been backfilled.
- It is anticipated that groundwater will be under control with the deep wells, and additional sumps will handle any water encountered in the trench during the excavations. The contractor will re-evaluate and install as required if a vacuum pump system is needed.
Week Ending January 13, 2023
Construction activities for this week consisted of the following:
- Northern continued driving steel sheeting using a hydraulic hammer within the excavated pavement along the first 300 feet of the interceptor alignment.
- The well point dewatering system is running continuously on a 24/7 basis while construction is on-going.
- Traffic will continue to be detoured per the construction signage and the message boards provided for the project.
- Site cleanup takes place at the end of each day
- Northern will also be working on site on Saturdays for the next several weeks.
Northern will resume work on-site next week (week of 1/16/2023) and the following work activities are anticipated to occur:
- No work on site on Monday, 1/16 in observance of Martin Luther King Jr. Day
- Northern will continue to drive the remainder of the first 300 feet of sheeting and will continue lagging
- Excavation and pipeline installation will start. It is anticipated that groundwater will be under control with the deep wells. Any water encountered in the trench during the excavation will be handled by additional sumps. Should a vacuum pump system be required, the contractor will re-evaluate and install as required.
- Geotechnical monitors will continue to be monitored daily during construction, including vibration.
Week Ending January 6, 2023
Construction activities for this week consisted of the following:
- Northern continued driving steel sheeting using a hydraulic hammer within the excavated pavement along the first 300 feet of the interceptor alignment.
- The well point dewatering system was activated this week and will be running continuously on a 24/7 basis while construction is on-going.
- Northern installed additional security fencing on jersey barriers near the Water Street rotary for protection of existing crew and equipment.
- Site cleanup will take place on Friday in preparation for the weekend.
- Traffic will continue to be detoured per the construction signage and the message boards provided for the project
Northern will resume work on-site next week (week of 1/9/2023) and the following work activities are anticipated to occur:
- Northern will have two crews working on-site next week:
- one crew will continue to drive sheeting within the excavated pavement along the first 300 feet of the project,
- the second crew will begin excavation to below pipe subgrade at the manhole closest to the Water Street rotary. Once excavation is below pipe subgrade, Northern will connect the new 30” PVC gravity sewer interceptor to the existing 30” pipe stub and proceed with the gravity sewer interceptor installation.
- Vibration monitors will be recording vibration activities on site as the contractor drives sheeting below grades. Should vibration readings exceed thresholds, effort will stop, and appropriate adjustments will be made to mitigate this issue.
- Geotechnical monitors will be monitored daily during construction activities to ensure there will be no movements of sidewalks, walls, and other features along the alignment.