Following the close of the public comment period in July 2009, The Port Authority of NY and NJ, the project sponsor, chose the New Alignment South as its proposed alignment. The USCG identified the New Alignment South as the Preferred Alternative for presentation and evaluation in the FEIS.
The Preferred Alternative consists of a cable-stayed replacement bridge on an alignment south of the existing bridge, and removal of the existing bridge after construction of the new bridge. The replacement bridge would consist of the following components:
- six 12-foot-wide travel lanes, three on each roadway deck (i.e., one roadway for eastbound traffic and one roadway for westbound traffic);
- a 12-foot-wide outer shoulder on each roadway;
- a 5-foot-wide inner shoulder on each roadway;
- a minimum 10-foot-wide sidewalk/bikeway along the northern edge of the westbound roadway; and
- a central area to be maintained between the eastbound and westbound roadway decks with sufficient width to accommodate the provision of transit service, should future conditions warrant inclusion of such service during the service life of the bridge.
The maximum out-to-out width of the main span of the bridge would be 210 feet. Part of that width comprises a 65-foot-wide central area between the eastbound and westbound decks, which accommodates the towers and support cables, as well as the 27-foot-wide potential mass transit corridor. Navigational clearance beneath the new bridge is proposed to be a minimum of 135 feet above mean high water (MHW) at the channel margins, equal to the minimum vertical clearance of the existing bridge. The main piers are proposed to be constructed 900 feet apart, an increase from the existing horizontal separation of 617 feet, thereby removing all bridge structure-related hazards from the Arthur Kill’s 500-foot navigation channel. The elevation of the two bridge towers is proposed to be 272 feet above mean sea level (MSL), as compared to the 248 feet above MSL associated with the existing bridge’s truss superstructure.
Other elements of the Preferred Alternative include:
- new approach spans at both the New Jersey and the New York ends of the new bridge with roadway dimensions similar to the bridge section;
- a 50-foot wide buffer on both sides of the replacement bridge and approach spans;
- permanent right-of-way fencing at ground level along both sides of the proposed replacement bridge approach spans, except through open waters;
- a permanent access road located generally below the proposed replacement bridge approach spans for purposes of construction, maintenance and security;
- replacement of the Travis Branch railroad bridge over I-278 in Staten Island in order to accommodate the wider roadway;
- re-alignment of Gulf Avenue in Staten Island; and
- construction staging areas of approximately five acres on each side of the Arthur Kill, which are required for storage of the materials, pre-assembly activities and office space for the construction effort.
The existing bridge, including its main truss span, New Jersey and New York approach spans and abutments, would be entirely demolished and removed, after construction of the new bridge is completed.
The Port Authority anticipates that the construction period for the new bridge and demolition of the existing bridge would range between 52 and 60 months, depending on the type of superstructure (i.e., steel girder, pre-cast/stressed concrete, or segmental concrete) to be selected for the main bridge span and its approaches.
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