Hurricane Barriers: U.S. Engineering Solutions

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Fox Point Hurricane Barrier, Providence, Rhode Island

Evening photo of bridge / open hurricane barrier in Providence, Rhode Island
Fox Point Hurricane Barrier, Providence, Rhode Island. Photo ©DACphoto, Dan Connolly, flickr.com, CC BY 2.0

In Rhode Island, Hurricane Sandy's 2012 mighty storm surge was blocked by a 1966 piece of engineering. What is a hurricane barrier and how does it work?

Fox Point Hurricane Barrier Fast Facts:

Where: Fox Point in East Providence, Rhode Island, situated across the Providence River, which flows into Narragansett Bay
When Constructed: 1960-1966
Size: 3,000-foot long, 25 foot high
Storm Tide Protection: 20 feet above sea level
Cost: $16 million (1960 dollars), 30% financed by state and local government
System: three Tainter gates, five pumps for river water, two 10- to 15-foot high stone and earth levees or dikes along the river's bank

How Does it Work?

Three Tainter or radial gates are closed, providing a half mile long, 25 foot high barrier between the City of Providence and the waters from Narragansett Bay. Water flowing down the Providence River is pumped out as it builds up behind the closed gates. The pumping station, 213 feet long and 91 feet wide, is constructed of reinforced concrete and brick. Five pumps have a capacity of pumping 3,150,000 gallons of riverwater per minute into Narragansett Bay.

Does a Hurricane Barrier Need a Pumping Station?

Design depends on conditions. The pumping station at Fox Point Hurricane Barrier is an important element to protecting the City of Providence. Without pumping out river water when the river is "dammed" by the gates, a reservoir would form and flood the city—just what Providence is trying to avoid.

Is a Hurricane Barrier a Dam?

Yes, and no. A dam certainly is a water barrier, but dams and reservoirs generally are not constructed for emergency use only. The sole purpose of a hurricane barrier is for protection from a storm surge or storm tide. The City of Providence has defined two central functions for Fox Point:

  1. "to retard high tides from potential storm surges in Narragansett Bay"
  2. "to maintain river flow such that water levels do not get too high behind the barrier"

What is a Storm Surge or Storm Tide?

A hurricane is a low-pressure center. Over land, low-pressure centers are not strong enough to move earth. However, low-pressure centers that are over water can actually push and move the water. Hurricane-force winds blow water not only creating waves, but also creating a dome or surge of high water. Along with a normal high tide, a storm surge can create an extreme storm tide in addition to the waves blown by severe hurricane wind. Hurricane barriers provide protection to anticipated storm tides.

Is a Storm Surge a Tsunami?

A storm surge is NOT a tsunami or tidal wave, but it is similar. Storm surge is an abnormal sea level rise, usually caused by extreme weather. The super-high tide also has waves, but the waves are not as dramatically high as a tsunami. Tsunamis are literally "harbor waves" caused by an underground disturbance, like an earthquake. Extreme flooding is the result of both events.

Living Near Water:

When we look at a map of where people live, it's not difficult to imagine how vulnerable life and property can be to severe weather. Although constructing tsunami-proof buildings along the shorelines is an option, a rising storm tide can be relentless. The U.S. National Hurricane Center has provided an Example of Storm Surge (Flash plug-in required). In this animation, storm surge along with pounding waves are no match to the small barrier protecting the structure.

Fox Point Barrier History:

  • September 1938, the New England Hurricane: $200 million property damage; 250 deaths; 3.1 inches of rain
  • August 1954, Hurricane Carol: $41 million property damage; flood tides at high tide, 13 feet above normal
  • Flood Control Act of 1958 authorized construction
  • U.S. Army Corps of Engineers (USACE) took control on Febrauary 2010, saving the City of Providence hundreds of thousands of dollars each year; the City maintains the dike and levee system.
  • In 2011, the barrier was used twelve times.

Learn More:

Sources: Emergency Management Agency, City of Providence; Fox Point Hurricane Barrier Facts, PDF document from the City of Providence at www.providenceri.com/efile/705; Update Report for Rhode Island, U.S. Army Corps of Engineers, New England District, July 31, 2012 at www.nae.usace.army.mil/news/Reports/ri.pdf. [websites accessed November 5, 2012]

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What is a Tainter Gate?

Open tainter gate at the hurricane barrier in Providence, Rhode Island
Open Tainter Gate at Fox Point Hurricane Barrier, Providence, Rhode Island. Photo © Jef Nickerson, Attribution-ShareAlike 2.0 Generic (CC BY-SA 2.0), flickr.com

The tainter gate was invented in the 19th century by American engineer and Wisconsin native Jeremiah Burnham Tainter. The curved gate is attached to one or more truss-like, triangular framework pieces. The wide end of the triangle framework is attached to the curved gate, and the apex point of the truss rotates to move the gate.

The tainter gate is also known as a radial gate. The water pressure actually helps move the gate up and down. The end effect is similar to the vertical Watergates in Japan, but the engineering is much different.

See How It Works:
YouTube Animation by Arif Setya Budi
Animated GIF provided by the Dunn County Historical Society, Wisconsin

Tainter Gates in Providence, Rhode Island:

Tainter gates at the Fox Point Hurricane Barrier protect the city of Providence from Narragansett Bay / Atlantic Ocean storm tides. Each gate is:

  • 40 feet square
  • 53 tons
  • curved outward toward the Bay to break the impact of the waves
  • lowered by gravity at 1.5 feet per minute (takes approximately 30 minutes to lower)
  • raised in approximately two hours
  • powered mechanically by three horsepower electrical motors; if necessary, the gates can be lowered and raised manually

Learn More:

Source: Fox Point Hurricane Barrier Facts (PDF document from the City of Providence); [accessed November 5, 2012]