CONCORD, Mass. --
The city of Boston is seeking a permit from the U.S. Army Corps of Engineers, New England District to conduct work in the waters of the U.S. in conjunction with the removal of the Northern Avenue Bridge, and the construction of a replacement bridge. This work is proposed in the Fort Point Channel, Boston Inner Harbor, Boston, Massachusetts.
The proposed work will include the removal of the existing deteriorated swing bridge structure and three supporting piers down to 2 feet below the mudline, removal of the existing Bridge Tender’s House north of the bridge, removal down to 2 feet below the mudline of the approximately 300 existing wooden pilings. The replacement work will involve the installation of six new piers to support the new bridge structure and the installation of approximately 130 14” diameter steel pipes to support the promenade and new fender system.
The primary purpose of the proposed replacement bridge with promenade will be to provide pedestrian and bicycle access and enjoyment of the waterfront but it will also allow for potential bus transit access. The new proposed bridge will have a travel width of 40-feet as it enters Fort Point Channel from the west, and will gradually divide into two separate travel lanes measuring 24 feet wide each, which separate in the middle and then will join back together again at the eastern extent of the promenade. Walkways down to the promenade will be located at the points where the travel lanes separate. It will be higher over the primary navigational crossing to allow for a fixed bridge and for climate resiliency.
The proposed work includes removal of the existing superstructure via barge-mounted cranes. The Bridge Tender’s House will also be demolished at this time. Steel sheeting cofferdams will then be installed around the existing bridge piers to facilitate their demolition and around the locations of the proposed new piers. A cofferdam system will also be installed along the eastern and western seawall to facilitate the reconstruction of the abutments.
Installation of the new piers will require foundation excavation, installation of approximately 160 18” diameter steel pipes, and the pouring of concrete. Demolition of the old piers will require excavation down to 2 feet below the mudline and then backfilling with clean, suitable material. Up to 2,407 cubic yards of material will be excavated over 38,741 square feet of subtidal bottom to perform the work. This removed material will be taken away to be dewatered and then disposed of at an approved facility.
This proposed project will permanently impact 2,488 square feet of essential fish habitat (EFH). However, the removal of the existing bridge piers and 300 wooden pilings will result in the restoration of 3,913 square feet of EFH. This habitat consists of sand and silt.
The dredging/excavation portion of this project will temporarily impact approximately 38,741 square feet of EFH. Loss of this habitat may adversely affect species that use these waters and substrate necessary for fish for spawning, breeding, feeding or growth to maturity.
The application for the federal permit was filed with the Corps in compliance with Section 404 of the Clean Water Act, which regulates the discharge or fill of material in U.S. waters, including wetlands and/or Section 103 of the Marine Protection Research and Sanctuaries Act of 1972, as amended. The public notice, with more specifics on the work proposed by the city of Boston, can be viewed on the Corps website at https://www.nae.usace.army.mil/Missions/PublicNotices/.
The activities proposed herein may also require permission from the Corps pursuant to Section 408 because they will alter or temporarily or permanently occupy or use a Corps federally authorized Civil Works project known as Fort Point Channel, Boston, Mass. A decision on a Section 408 request is a Federal action, and therefore subject to NEPA and other environmental compliance requirements. A permit pursuant to Section 10/404/103 shall not be granted until the Section 408 permission is issued. Through this public notice we are soliciting information necessary to inform the Corps evaluation and review. The point of contact for Section 408 issues for this project is Mark Cutter, who can be reached by phone at 978-318-8776 or by email at email@example.com
The Corps will evaluate the bridge removal activities under Section 10 of the Rivers and Harbors Act and Section 404 of the Clean Water Act; and discharge of fill material associated with the bridge replacement work under the authority of Section 404 of the Clean Water Act. The United States Coast Guard (USCG) will have primary authority for overseeing the construction of the new bridge over a navigable water.
Public comments on this work proposed by the city of Boston (file # NAE-2015-02009) should be forwarded no later than July 2, 2020 to the U.S. Army Corps of Engineers, New England District, Regulatory Division (ATTN: Ruthann Brien), 696 Virginia Road, Concord, MA 01742-2751. Additional information is available from Permit Project Manager Ruthann Brien at 978-318-8054 or toll free 800-343-4789 or 800-362-4367 (if calling from within Massachusetts) or by email to: firstname.lastname@example.org.