The Sundial Bridge (also known as the Sundial Bridge at Turtle Bay) is a
cantilever spar cable-stayed bridge
A cantilever spar cable-stayed bridge is a modern variation of the cable-stayed bridge. This design has been pioneered by the structural engineer Santiago Calatrava in 1992 with the Puente del Alamillo in Seville, Spain. In two of his designs th ...
for bicycles and pedestrians that spans the
Sacramento River
The Sacramento River ( es, Río Sacramento) is the principal river of Northern California in the United States and is the largest river in California. Rising in the Klamath Mountains, the river flows south for before reaching the Sacramento ...
in
Redding, California,
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territori ...
and forms a large
sundial. It was designed by
Santiago Calatrava
Santiago Calatrava Valls (born 28 July 1951) is a Spanish architect, structural engineer, sculptor and painter, particularly known for his bridges supported by single leaning pylons, and his railway stations, stadiums, and museums, whose sculp ...
and completed in 2004 at a cost of US$23.5 million. The bridge has become iconic for Redding.
Location
The Sundial Bridge provides pedestrian access to the north and south areas of
Turtle Bay Exploration Park
Turtle Bay Exploration Park, located in Redding, California, is a non-profit 300-acre gathering place featuring the Sundial Bridge, a museum, forestry and wildlife center, arboretum and botanical gardens. The park is located at gateway to the ...
, a complex containing environmental, art and history museums and the McConnell Arboretum and Gardens. It also forms the gateway to the Sacramento River Trail,
a trail completed in 2010 that extends along both sides of the river and connects the bridge to the
Shasta Dam
Shasta Dam (called Kennett Dam before its construction) is a concrete arch-gravity dam across the Sacramento River in Northern California in the United States. At high, it is the List of tallest dams in the United States, eighth-tallest dam in ...
. Drift boats of fishermen are often seen passing beneath the bridge as they fish for salmon, steelhead and rainbow trout.
[.] In the distance,
Mount Shasta
Mount Shasta ( Shasta: ''Waka-nunee-Tuki-wuki''; Karuk: ''Úytaahkoo'') is a potentially active volcano at the southern end of the Cascade Range in Siskiyou County, California. At an elevation of , it is the second-highest peak in the Cascades ...
is barely visible. Shasta Bally is visible to the West looking upstream the Sacramento.
Sundial
The support tower of the bridge forms a single mast that points due north at a cantilevered angle (42 degrees), allowing it to serve as the
gnomon of a sundial. It has been billed as the world's largest sundial,
[.] although
Taipei 101
Taipei 101 (; stylized as TAIPEI 101), formerly known as the Taipei World Financial Center, is a supertall skyscraper in Taipei, Taiwan. This building was officially classified as the world's tallest from its opening in 2004 until the 2009 ...
and the associated sundial design of its adjoining park are much larger. The Sundial Bridge gnomon's shadow is cast upon a large dial to the north of the bridge, although the shadow cast by the tower is exactly accurate on only one day in a year – the summer
solstice
A solstice is an event that occurs when the Sun appears to reach its most northerly or southerly excursion relative to the celestial equator on the celestial sphere. Two solstices occur annually, around June 21 and December 21. In many countr ...
, June 20 or 21. The time is given as
Pacific Daylight Time
The Pacific Time Zone (PT) is a time zone encompassing parts of western Canada, the western United States, and western Mexico. Places in this zone observe standard time by subtracting eight hours from Coordinated Universal Time ( UTC−08:00 ...
. The tip of the shadow moves at approximately one foot per minute so that the Earth's rotation about its axis can be seen with the naked eye.
[. Back cover.]
Design
The Sundial Bridge is a
cantilever spar cable-stayed bridge
A cantilever spar cable-stayed bridge is a modern variation of the cable-stayed bridge. This design has been pioneered by the structural engineer Santiago Calatrava in 1992 with the Puente del Alamillo in Seville, Spain. In two of his designs th ...
, similar to Calatrava's earlier design of the ''
Puente del Alamillo
The Alamillo Bridge ( es, Puente del Alamillo) is a structure in Seville, Andalucia (Spain), which spans the Canal de Alfonso XIII, allowing access to La Cartuja, a peninsula located between the canal and the Guadalquivir River. The bridge was ...
'' in
Seville
Seville (; es, Sevilla, ) is the capital and largest city of the Spanish autonomous community of Andalusia and the province of Seville. It is situated on the lower reaches of the River Guadalquivir, in the southwest of the Iberian Peninsula ...
, Spain (1992). This type of bridge does not balance the
forces by using a
symmetrical
Symmetry (from grc, συμμετρία "agreement in dimensions, due proportion, arrangement") in everyday language refers to a sense of harmonious and beautiful proportion and balance. In mathematics, "symmetry" has a more precise definiti ...
arrangement of
cable
Cable may refer to:
Mechanical
* Nautical cable, an assembly of three or more ropes woven against the weave of the ropes, rendering it virtually waterproof
* Wire rope, a type of rope that consists of several strands of metal wire laid into a hel ...
forces on each side of its support tower; instead, it uses a
cantilever
A cantilever is a rigid structural element that extends horizontally and is supported at only one end. Typically it extends from a flat vertical surface such as a wall, to which it must be firmly attached. Like other structural elements, a cant ...
tower, set at a 42-degree angle
[.] and loaded by cable stays on only one side. This design requires that the spar resist
bending
In applied mechanics, bending (also known as flexure) characterizes the behavior of a slender structural element subjected to an external load applied perpendicularly to a longitudinal axis of the element.
The structural element is assumed to ...
and
torsional
In the field of solid mechanics, torsion is the twisting of an object due to an applied torque. Torsion is expressed in either the pascal (Pa), an SI unit for newtons per square metre, or in pounds per square inch (psi) while torque is expressed ...
forces and that its
foundation
Foundation may refer to:
* Foundation (nonprofit), a type of charitable organization
** Foundation (United States law), a type of charitable organization in the U.S.
** Private foundation, a charitable organization that, while serving a good cause ...
resists overturning. While this leads to a less structurally efficient structure, the
architect
An architect is a person who plans, designs and oversees the construction of buildings. To practice architecture means to provide services in connection with the design of buildings and the space within the site surrounding the buildings that h ...
ural statement is dramatic. The bridge is in length and crosses the river without touching the water, a design criterion that helps protect the salmon spawning grounds beneath the bridge.
[''Santiago Calatrava's Sundial Bridge: Angle of Inspiration'', Mill Valley Film Group, 2004.] The cable stays are not centered on the walkway but instead divide the bridge into a major and minor path.
The cable for the bridge totals and was made in England. The dial of the sundial and a small plaza beneath the support tower are decorated with broken white tile from Spain. The bridge's deck is surfaced with translucent structural glass from Quebec, which is illuminated from beneath and glows aquamarine at night. The steel support structure of the bridge was made in
Vancouver, Washington
Vancouver is a city on the north bank of the Columbia River in the U.S. state of Washington, located in Clark County. Incorporated in 1857, Vancouver has a population of 190,915 as of the 2020 census, making it the fourth-largest city in Was ...
and transported in sections by truck to Redding.
Budget
Plans for the Sundial Bridge began in the 1990s, when the city of Redding budgeted $3 million for a pedestrian bridge across the river. However, costs escalated after Calatrava's design was chosen in 1996,
[.] and the project became a controversial one within Redding, supported by a small group of doctors, lawyers, and other professionals but opposed by other residents who thought it would be too expensive
[.] and who favored a more "folksy" covered bridge design.
[.] The bridge was completed in 2004, three years later than originally planned,
at a cost of $23.5 million, with funding from the Redding-based McConnell Foundation.
[.] The expense was justified on the basis that it would increase tourism in the Redding area,
which also features
Shasta Dam
Shasta Dam (called Kennett Dam before its construction) is a concrete arch-gravity dam across the Sacramento River in Northern California in the United States. At high, it is the List of tallest dams in the United States, eighth-tallest dam in ...
as another architectural marvel, and it has been successful in that goal.
Tourism
In the fiscal year following its grand opening, Turtle Bay Exploration Park, adjacent to the bridge, saw a 42-percent increase in its visitation.
As of 2011, Redding's city manager stated that the bridge "continues to generate millions of dollars worth of commerce and tourism each year".
In media
The bridge is the cover image of a general physics textbook by Serway and Jewett, demonstrating the bridge resisting forces of wind and gravity.
Pink Sundial Bridge
In 2009, Nor-Cal Think Pink, a non-profit organization dedicated to raising awareness of the importance of early detection of breast cancer, received approval from the City of Redding to illuminate the Sundial Bridge in pink for its Think Pink Day. The event now takes place annually.
"3 nights of pink lights"
Redding.com
See also
*Puente de la Mujer
The Puente de la Mujer (Spanish for "Woman's Bridge") is a rotating footbridge for Dock 3 of the Puerto Madero commercial district of Buenos Aires, Argentina. It is of the cantilever spar cable-stayed bridge type and is also a swing bridge, but som ...
, Buenos Aires
Buenos Aires ( or ; ), officially the Autonomous City of Buenos Aires ( es, link=no, Ciudad Autónoma de Buenos Aires), is the capital and primate city of Argentina. The city is located on the western shore of the Río de la Plata, on South ...
, Argentina
Argentina (), officially the Argentine Republic ( es, link=no, República Argentina), is a country in the southern half of South America. Argentina covers an area of , making it the second-largest country in South America after Brazil, th ...
*Samuel Beckett Bridge
Samuel Beckett Bridge () is a cable-stayed swingbridge in Dublin, Ireland that joins Sir John Rogerson's Quay on the south side of the River Liffey to Guild Street and North Wall Quay in the Docklands area.
Design and construction
Architect ...
, Dublin
Dublin (; , or ) is the capital and largest city of Ireland. On a bay at the mouth of the River Liffey, it is in the province of Leinster, bordered on the south by the Dublin Mountains, a part of the Wicklow Mountains range. At the 2016 c ...
, Ireland
Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic Ocean, in Northwestern Europe, north-western Europe. It is separated from Great Britain to its east by the North Channel (Grea ...
*Puente de la Unidad
Puente de la Unidad or Viaducto de la Unidad is a cantilever spar cable-stayed bridge designed by Óscar Bulnes that crosses the Santa Catarina River and connects the cities of Monterrey and San Pedro Garza García in the Mexican state of Nuev ...
, Monterrey, Mexico
Mexico (Spanish: México), officially the United Mexican States, is a country in the southern portion of North America. It is bordered to the north by the United States; to the south and west by the Pacific Ocean; to the southeast by Guatema ...
*Puente del Alamillo
The Alamillo Bridge ( es, Puente del Alamillo) is a structure in Seville, Andalucia (Spain), which spans the Canal de Alfonso XIII, allowing access to La Cartuja, a peninsula located between the canal and the Guadalquivir River. The bridge was ...
, Seville
Seville (; es, Sevilla, ) is the capital and largest city of the Spanish autonomous community of Andalusia and the province of Seville. It is situated on the lower reaches of the River Guadalquivir, in the southwest of the Iberian Peninsula ...
, Spain
, image_flag = Bandera de España.svg
, image_coat = Escudo de España (mazonado).svg
, national_motto = ''Plus ultra'' (Latin)(English: "Further Beyond")
, national_anthem = (English: "Royal March")
, i ...
References
External links
*
Sundial Bridge official site
(archived)
* {{Structurae, id=20002419, title=Turtle Bay Sundial Bridge
Bridges completed in 2004
Bridges over the Sacramento River
Cable-stayed bridges in the United States
Pedestrian bridges in California
Bridges by Santiago Calatrava
Sundials
Towers in California
Redding, California
Transportation buildings and structures in Shasta County, California
Neo-futurism architecture
Steel bridges in the United States
Cantilever bridges in the United States
Inclined towers
Buildings and structures in Redding, California
2004 establishments in California