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1970

Union Canal Tunnel
Society: ASCE Main Category: Civil Sub Category: Tunnels Era: 1800-1829 DateCreated: 1828 Union Canal Lebanon State: PA Zip: Country: USA Website: http://www.asce.org/Project/Union-Canal-Tunnel/ Creator: Ives, John

According to oral history, George Washington visited the canal diggings in 1792, and then again in 1794, while he was accompanying troops to suppress the Whiskey Rebellion in Western Pennsylvania. 

YearAdded:
1970
Image Credit: Courtesy Flickr/Ospreye (CC BY 2.0) Image Caption: Union Canal Tunnel Era_date_from: 1828
Theodore Roosevelt Dam
Society: ASCE Main Category: Civil Sub Category: Water Supply & Control Era: 1910-1919 DateCreated: 1911 Theodore Roosevelt Dam Tonto National Forest State: AZ Zip: 85545 Country: USA Website: http://www.asce.org/Project/Theodore-Roosevelt-Dam---Salt-River-Project/ Creator:

The first electric power generated by the Theodore Roosevelt Dam for commercial use was transmitted over a high-voltage line to Phoenix, where it was employed to operate the city's new streetcar system. 

YearAdded:
1970
Image Credit: Courtesy Bureau of Reclamation (CC BY-SA 2.0) Image Caption: Theodore Roosevelt Dam Era_date_from: 1911
Potowmack Canal and Locks
Society: ASCE Main Category: Civil Sub Category: Water Transportation Era: 1750-1799 DateCreated: 1799 Great Falls Park Fairfax County State: VA Zip: Country: USA Website: http://www.asce.org/Project/Potowmack-Canal-and-Locks/ Creator: Washington, George, Potowmack Canal Company

These canals and locks are a part of the first extensive system of canal and river navigation works undertaken in the United States. The idea for the canal was proposed by George Washington, when, as an engineer, surveyor and military emissary for Virginia, he saw the need for a trade route west beyond the Allegheny Mountains. In order to do create this route, it was necessary to try to tame the Potomac River which was a wild, unruly stream which only the hardiest of rivermen ever attempted.

YearAdded:
1970
Image Credit: Courtesy Flickr/Rudi Riet (CC BY-SA 2.0) Image Caption: Potowmack Canal and Locks Era_date_from: 1799
Frankford Avenue Bridge
Society: ASCE Main Category: Civil Sub Category: Bridges Era: 1600s DateCreated: 1697 Pennypack Park Philadelphia State: PA Zip: 19114 Country: USA Website: http://www.asce.org/Project/Frankford-Avenue-Bridge/ Creator: Unknown

"For 273 years, the little stone bridge that carries Frankford Ave. across Pennypack Creek has been doing its humble job with a minimum of attention..." 
 - Gerald McKelvey, The Philadelphia Inquirer, September 16, 1970

YearAdded:
1970
Image Credit: Public Domain (National Park Service) Image Caption: Frankford Avenue Bridge Era_date_from: 1697
Cornish - Windsor Covered Bridge
Society: ASCE Main Category: Civil Sub Category: Bridges Era: 1860-1869 DateCreated: 1866 Windsor Covered Bridge Cornish State: VT Zip: 03745 Country: USA Website: http://www.asce.org/project/cornish-windsor-covered-bridge/ Creator: Town, Ithiel

The Cornish-Windsor Covered Bridge is the longest wooden bridge in the United States and the longest two-span, covered bridge in the world. It is also a classic example of wooden bridge-building in 19th-century America. With copious supplies of timber at hand and a generous reserve of carpentry skills available, bridge builders in early America quickly discarded the masonry arches prevalent in the Old World. Instead, they opted for a revival of timber-truss designs dating from 14th century Europe.

YearAdded:
1970
Image Credit: Courtesy Flickr/aussiegtl (CC BY 2.0) Image Caption: Cornish - Windsor Covered Bridge Era_date_from: 1866
Bridgeport Covered Bridge
Society: ASCE Main Category: Civil Sub Category: Bridges, Transportation Era: 1860-1869 DateCreated: 1862 Yuba River Penn Valley State: CA Zip: 95946 Country: USA Website: http://www.asce.org/Project/Bridgeport-Covered-Bridge/ Creator: Virginia City Turnpike Company, Burr, Theodore

A product of the Northern California Gold Rush, the Bridgeport Covered Bridge is believed to be the longest, single-span, wooden covered bridge in the United States. Crossing the south fork of the Yuba River at a span of 233 feet, the bridge was built by the Virginia City Turnpike Company as part of a 14-mile toll road authorized by the California state legislature. The toll road was an essential link connecting Virginia City, Nevada, and the silver-producing Comstock Lode with the centers of California commerce.

YearAdded:
1970
Image Credit: Courtesy Flickr/Rick Cooper (CC BY 2.0) Image Caption: The Bridgeport Covered Bridge, one of the longest covered bridges in the nation Era_date_from: 1862
Ascutney Mill Dam
Society: ASCE Main Category: Civil Sub Category: Dams Era: 1830-1839 DateCreated: 1834 Mill Brook Windsor State: VT Zip: 05089 Country: USA Website: http://www.asce.org/Project/Ascutney-Mill-Dam/ Creator: Beard, Ithamar , Cobb, Simeon

Ithamar A. Beard, an engineer of some prominence in New England, surveyed the mill brook and selected the best site for a storage dam. Contractor Simeon Cobb, knowledgeable of contemporary civil engineering practices, made major changes to the dam's original design, converting the linear dam into a gentle arch.

YearAdded:
1970
Image Credit: Courtesy Wikipedia/Ymblanter (CC BY-SA 3.0) Image Caption: The Ascutney Mill Arch-Gravity Dam Era_date_from: 1834
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Ascutney Mill Dam

Ithamar A. Beard, an engineer of some prominence in New England, surveyed the mill brook and selected the best site for a storage dam. Contractor Simeon Cobb, knowledgeable of contemporary civil engineering practices, made major changes to the dam's original design, converting the linear dam…

Read More
Bridgeport Covered Bridge

A product of the Northern California Gold Rush, the Bridgeport Covered Bridge is believed to be the longest, single-span, wooden covered bridge in the United States. Crossing the south fork of the Yuba River at a span of 233 feet, the bridge was built by the Virginia City Turnpike Company as…

Read More
Cornish - Windsor Covered Bridge

The Cornish-Windsor Covered Bridge is the longest wooden bridge in the United States and the longest two-span, covered bridge in the world. It is also a classic example of wooden bridge-building in 19th-century America. With copious supplies of timber at hand and a generous reserve of carpentry…

Read More
Frankford Avenue Bridge

"For 273 years, the little stone bridge that carries Frankford Ave. across Pennypack Creek has been doing its humble job with a minimum of attention..." 
 - Gerald McKelvey, The Philadelphia Inquirer, September 16, 1970

Built more than a century before the reign of Napoleon,…

Read More
Potowmack Canal and Locks

These canals and locks are a part of the first extensive system of canal and river navigation works undertaken in the United States. The idea for the canal was proposed by George Washington, when, as an engineer, surveyor and military emissary for Virginia, he saw the need for a trade route west…

Read More
Theodore Roosevelt Dam

The first electric power generated by the Theodore Roosevelt Dam for commercial use was transmitted over a high-voltage line to Phoenix, where it was employed to operate the city's new streetcar system. 

The Salt River Project, including the Theodore Roosevelt Dam, was the first major…

Read More
Union Canal Tunnel

According to oral history, George Washington visited the canal diggings in 1792, and then again in 1794, while he was accompanying troops to suppress the Whiskey Rebellion in Western Pennsylvania. 

The Union Canal Tunnel was a crucial structure allowing the connection of the eastern and…

Read More

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