Cambridge Turnpike Improvement Project

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Background
Cambridge Turnpike Improvement Project (CTIP) is one of the major projects going on in the Town of Concord. The project, as its name implies, is located on Cambridge Turnpike on the east side of Town focusing on the section of roadway from Routes 2 and 2A (Crosby’s Corner) to Lexington Road. 
This section of roadway traverses Mill Brook in two locations as identified on the map.

Portions of Cambridge Turnpike were originally identified as problem areas due to significant flooding from the rise in water elevation of Mill Brook during significant rain storms. The frequent road closures due to flooding were affecting the ability of the Town’s residents to use the road, especially the residents and businesses on the roadway. They had to deal with the flooding of their residences and facilities plus damage to their septic systems, the roadway, and the utilities in the road. The Town, with recommendations from Concord Public Works (CPW) and the Public Works Commission (PWC) decided to undertake the CTIP to address the flooding, degradation of the roadway, and the associated utilities. The Town also decided to take this opportunity to integrate a multi‐modal approach to the design of the new roadway. The design incorporated a corridor that is passable for motorists, pedestrians, and cyclists. The multi‐modal improvements will complement the Town’s character and are in‐line with Town initiatives to promote multiple means of transportation. 
Another important portion of the development is to protect the environmental and historical resources of the area while enhancing the experience of the residents using the resources.
Design and Permitting
To assist the Town in the challenges presented by the CTIP, Louis Berger Group (LBG) was selected by the Town and  awarded the contract for the initial phase of project  design. LBG  came up with a conceptual design that addressed the roadway flooding, flooding of homes and businesses and the impacts to their septic systems, and roadway utilities. The primary design also included replacing and raising the two Mill Brook crossings by constructing a new bridge, new box culverts, and new retaining walls. The Town with the assistance of the LBG Team implored involvement from the public/community and established a comprehensive public involvement program. The aim of this program was to acquire the concerns of the community and try to incorporate their input into the design. A questionnaire was provided to gather the community’s input. The information gathered was carefully considered in advancing the design to complete the draft Preliminary Design Report (PDR). After gathering the communities input the Town recognized that the community was also interested in the following:
•       Flooding
•       Environmental  Impacts
•       Traffic Safety and Intersection Congestion
•       Roadway Width
•       Historical Preservation
•       Aesthetics ‐ Landscaping, Structures
The public/community had additional opportunity to review the draft PDR and provide feedback to the Town which was incorporated into the design to the greatest degree practical. The PDR and subsequent design updates, along with Public Meeting information are available as links on this page.
The following was completed by LBG for the initial phase of the project:
•      Flood study at the upper watershed of Mill Brook
•       A site survey
•       An initial evaluation of roadway and bridge alternatives
•      Traffic studies and evaluations
•      Conceptual intersection designs, and initial environmental permitting
Some information to note, as a result of the flood study the project team noticed that flood elevations for the upper Mill Brook watershed (from Main Street to Crosby Pond Dam) were too high, by approximately 3.5 to 4.5 feet for the 100‐year flood. Hence, a Letter of Map Revision (LOMR) was filed with FEMA in order to correct the official flood plan elevation. A LOMR was issued by FEMA on August 16, 2015 to revise flood elevations for the Cambridge Turnpike area. These revised elevations were used as the baseline for the design, allowing the project’s impacts to be more accurately calculated to support the environmental permitting process.After completion of the initial phase, the Town decided to advance the project to the development phase. CMA Engineers, Inc. (CMA) was selected by the Town and awarded the contract for advancing the CTIP through 100% design, permitting, project bidding, award, and provide resident engineering services during construction. Also during this time the Town contacted National Grid to inform them that significant construction was to be done on this roadway. Because of the flooding and the age of the gas main in Cambridge Turnpike, National Grid decided to replace the existing main. Additionally, the overhead electrical lines, telephone lines, and communication lines owned by CMPL, Comcast, and Verizon were to be relocated underground to the greatest degree practicable. This gas main and utility line replacement was incorporated into CMA’s design.After the completion of the design and permitting, the Town and the CMA team decided to have the project bid as two separate construction contracts due to the unique requirements of each phase of construction. J. Tropeano Inc. was awarded phase I (identified as Areas 1 and 3 on the site map) of the contract, while George Cairns & Sons, Inc. was awarded phase II (Identified as Areas 2 and 4 on the site map). The construction was broken up in this way because Areas 1 and 3 were a more conventional roadway reconstruction while Areas 2 and 4 have to do with a bridge and large culverts to cross Mill Brook.
Construction
Construction of the project started in spring of 2018, and the original construction schedule was to progress through 2 construction seasons: 2018‐2019 & 2019‐2020. National Grid’s gas main replacement was planned to start in the spring of 2018 in preparation for the start of the conventional corridor improvements. Unfortunately due to National Grid’s labor issues, the gas replacement work started later than expected in the spring of 2019, but the majority of the work has now been completed. National Grid has also installed their new transmission line in Areas 1, 2 and 3.The following is the remaining National Grid construction to be completed in 2020
•      Area 2: Install gas pipe across the bridge
•      Area 3: Tie over the old transmission line to the
       newly installed pipes.

Phase 1: Construction of Area 1 and Area 3 by J. Tropeano Inc. focused on conventional roadway and utilities construction between Lexington Road to Mill Brook Farm and from Hawthorne Lane to Sandy Pond Road. Included in the construction was roadway and sidewalk reconstruction, the replacement of Town owned drainage and water, the reconstruction of the electric utility and the reconstruction of the private communications utilities. Construction completed in the 2018‐2019 season for Area 1 includes, water main, underground conduit, drainage, binder pavement, curbing, stone walls & partial sidewalk.Construction completed in the 2018‐2019 season for Area 3 includes, water main, underground conduit, binder pavement & stone walls.
The following is the remaining Phase I Construction to be completed in 2020:
•      Area  1:  Relocate  overhead  utilities,  complete  sidewalks,  brick  crossings,  final  paving  and landscaping.
•       Area 3: Complete drainage, curbing, sidewalks, final paving and landscaping.
Phase 2: Construction of Areas 2 and 4 by George Cairns & Sons, Inc. includes two sections of marsh crossings that included bridge in Area 2, and culverts in Area 4. The two marsh crossing areas include the installation of deep ground improvements to support both sections of roadway improvement and new retaining walls to minimize wetland filling that supported the elevated travel way out of the flood plain. The construction will replace a failing culvert system in Area 2 with a new 40‐foot span bridge and replace two failing metal culverts in Area 4 with new concrete box culverts while reconstructing utilities within the area. As a result of the construction, the Town will utilize road closures for Phase II of the contract’s construction. Residents on Cambridge Turnpike and surrounding neighborhoods will be provided access to their homes during all phases of construction. Construction completed in the 2018‐2019 season for Area 2 include, partial water main, partial bridge construction, retaining walls, utility conduits, drainage, roadway construction, and binder pavement. 
The following is the remaining Phase II Construction to be completed in 2020:
•      Area 2: Complete bridge  work, complete water main, complete        retaining wall, sidewalks, and  roadway  construction.
•      Area 4: Culvert crossings at Crosby Pond, relocation of overhead utilities,    sidewalks,  retaining walls, roadway construction &  landscaping.
Communications
Communication to affected parties and abutters will continue throughout construction. Updates will be posted on the Town’s website and on the CTIP’s link. The Town strives to keep project construction on schedule while minimizing resident’s inconvenience and appreciates the continued support of the community. Because construction operations, portions of Cambridge Turnpike are currently closed, but two major detours and a third minor detour for local traffic only are currently operating. The southbound detour route is from Lexington Road to Bypass Road, and the southbound detour runs from Concord Turnpike to Walden Street. The local traffic only detour runs from Hawthorne Lane to Lexington Road. The map below shows the detour routes.
If there are any comments or questions please contact Concord Public Works by phone at 978‐318‐3210.
If you would like to be added to our project specific email list, please email Anna Trout.
Please bookmark this page and check back often for updates. We appreciate your interest and participation.


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