Piscataqua River Bridge
Encyclopedia
The Piscataqua River Bridge is a cantilever
ed through arch bridge that crosses the Piscataqua River
, connecting Portsmouth, New Hampshire
with Kittery, Maine
. Carrying six lanes of Interstate 95
, the bridge is the third modern span and first fixed crossing of the Piscataqua between Portsmouth and Kittery. The two older spans, the Memorial Bridge
and the Sarah Mildred Long Bridge
, are both lift bridge
s, built to accommodate ship traffic along the Piscataqua. The high arch design of the Piscataqua River Bridge eliminates the need for a movable roadway.
, Interstate 95 was routed along the New Hampshire Turnpike
, which had opened to traffic in 1950, and paralleled U.S. Route 1
through New Hampshire's seacoast
from the Massachusetts
border to the Turnpike's end at the Portsmouth Traffic Circle
. Between the traffic circle and the beginning of the Maine Turnpike, there was a gap in I-95 that was filled by the US-1 Bypass, crossing over the Sarah Mildred Long Bridge. Since the Long Bridge is a lift bridge with only a two lane roadway, it was far from meeting Interstate Highway standards
.
The decision was made to extend I-95 north from the New Hampshire Turnpike at Portsmouth and south from the Maine Turnpike in Kittery, and join the roads with an uninterrupted high speed span over the Piscataqua. Work on the bridge was completed in 1971, and the I-95 extension to it in Maine was completed the following year.
Cantilever
A cantilever is a beam anchored at only one end. The beam carries the load to the support where it is resisted by moment and shear stress. Cantilever construction allows for overhanging structures without external bracing. Cantilevers can also be constructed with trusses or slabs.This is in...
ed through arch bridge that crosses the Piscataqua River
Piscataqua River
The Piscataqua River, in the northeastern United States, is a long tidal estuary formed by the confluence of the Salmon Falls and Cocheco rivers...
, connecting Portsmouth, New Hampshire
Portsmouth, New Hampshire
Portsmouth is a city in Rockingham County, New Hampshire in the United States. It is the largest city but only the fourth-largest community in the county, with a population of 21,233 at the 2010 census...
with Kittery, Maine
Kittery, Maine
Kittery is a town in York County, Maine, United States. The population was 9,543 at the 2000 census. Home to the Portsmouth Naval Shipyard on Seavey's Island, Kittery includes Badger's Island, the seaside district of Kittery Point, and part of the Isles of Shoals...
. Carrying six lanes of Interstate 95
Interstate 95
Interstate 95 is the main highway on the East Coast of the United States, running parallel to the Atlantic Ocean from Maine to Florida and serving some of the most populated urban areas in the country, including Boston, Providence, New Haven, New York City, Newark, Philadelphia, Baltimore,...
, the bridge is the third modern span and first fixed crossing of the Piscataqua between Portsmouth and Kittery. The two older spans, the Memorial Bridge
Memorial Bridge (Portsmouth, New Hampshire)
The Memorial Bridge is a through truss lift bridge that carried U.S. 1 across the Piscataqua River between Portsmouth, New Hampshire and Badger's Island in Kittery, Maine USA. The bridge was closed permanently to vehicle traffic on July 27, 2011, with a replacement to be built by 2014.The lift span...
and the Sarah Mildred Long Bridge
Sarah Mildred Long Bridge
The Sarah Mildred Long Bridge is a lift bridge that carries the US 1 Bypass over the Piscataqua River between Portsmouth, New Hampshire and Kittery, Maine. The bridge is a double deck truss bridge, with the US 1 Bypass road deck above and a railroad bed below....
, are both lift bridge
Lift bridge
A vertical-lift bridge or lift bridge is a type of movable bridge in which a span rises vertically while remaining parallel with the deck....
s, built to accommodate ship traffic along the Piscataqua. The high arch design of the Piscataqua River Bridge eliminates the need for a movable roadway.
History
As part of the Interstate Highway SystemInterstate Highway System
The Dwight D. Eisenhower National System of Interstate and Defense Highways, , is a network of limited-access roads including freeways, highways, and expressways forming part of the National Highway System of the United States of America...
, Interstate 95 was routed along the New Hampshire Turnpike
Interstate 95 in New Hampshire
Interstate 95, the main Interstate Highway on the east coast of the United States, cuts through the Seacoast Region of New Hampshire. The majority of it, from the Massachusetts border to the Portsmouth Circle in Portsmouth, is the 14.29-mile Blue Star Turnpike or New Hampshire Turnpike, a toll...
, which had opened to traffic in 1950, and paralleled U.S. Route 1
U.S. Route 1
U.S. Route 1 is a major north–south U.S. Highway that serves the East Coast of the United States. It runs 2,377 miles from Fort Kent, Maine at the Canadian border south to Key West, Florida. U.S. 1 generally parallels Interstate 95, though it is significantly farther west between...
through New Hampshire's seacoast
Seacoast Region (New Hampshire)
The Seacoast Region is the southeast area of the U.S. state of New Hampshire. The region stretches 18 miles along the Atlantic Ocean from New Hampshire's border with Salisbury, Massachusetts to the Piscataqua River and New Hampshire's border with Kittery, Maine. The shoreline is generally very...
from the Massachusetts
Massachusetts
The Commonwealth of Massachusetts is a state in the New England region of the northeastern United States of America. It is bordered by Rhode Island and Connecticut to the south, New York to the west, and Vermont and New Hampshire to the north; at its east lies the Atlantic Ocean. As of the 2010...
border to the Turnpike's end at the Portsmouth Traffic Circle
Portsmouth Traffic Circle
The Portsmouth Traffic Circle is a four-point rotary in the city of Portsmouth, New Hampshire.-Description:The southern exit of the circle provides access to Interstate 95 north and south, although only northbound I-95 traffic enters here. The eastern and northern exits are part of the U.S. Route 1...
. Between the traffic circle and the beginning of the Maine Turnpike, there was a gap in I-95 that was filled by the US-1 Bypass, crossing over the Sarah Mildred Long Bridge. Since the Long Bridge is a lift bridge with only a two lane roadway, it was far from meeting Interstate Highway standards
Interstate Highway standards
Standards for Interstate Highways in the United States are defined by the American Association of State Highway and Transportation Officials in the publication A Policy on Design Standards - Interstate System...
.
The decision was made to extend I-95 north from the New Hampshire Turnpike at Portsmouth and south from the Maine Turnpike in Kittery, and join the roads with an uninterrupted high speed span over the Piscataqua. Work on the bridge was completed in 1971, and the I-95 extension to it in Maine was completed the following year.
See also
- Interstate 95 in New HampshireInterstate 95 in New HampshireInterstate 95, the main Interstate Highway on the east coast of the United States, cuts through the Seacoast Region of New Hampshire. The majority of it, from the Massachusetts border to the Portsmouth Circle in Portsmouth, is the 14.29-mile Blue Star Turnpike or New Hampshire Turnpike, a toll...
- Interstate 95 in MaineInterstate 95 in MaineIn the U.S. state of Maine, Interstate 95 is a long highway running from the New Hampshire border near Kittery, to the Canadian border near Houlton. It is the only two-digit Interstate Highway in Maine...