Carquinez Strait Powerline Crossing
Encyclopedia
Carquinez Strait Powerline Crossing was the world's first powerline crossing of a large river. It was built in 1901 for a 60 kV powerline operated by Bay Counties Power Companyto deliver electric power to Oakland, California
. For this a crossing of Carquinez Strait
was required, which has at its narrowest point a width of 1 kilometre (0.621372736649807 mi). Such a span width was impossible with wooden poles, which were common in those days. Installing an underwater cable was considered, but for reliability reasons an overhead powerline
was installed, which used at the north site of the river a 68 metres (223.1 ft) tall lattice tower and at the south site one with a height of 20 metres (66 ft).
Oakland, California
Oakland is a major West Coast port city on San Francisco Bay in the U.S. state of California. It is the eighth-largest city in the state with a 2010 population of 390,724...
. For this a crossing of Carquinez Strait
Carquinez Strait
The Carquinez Strait is a narrow tidal strait in northern California. It is part of the tidal estuary of the Sacramento and the San Joaquin rivers as they drain into the San Francisco Bay...
was required, which has at its narrowest point a width of 1 kilometre (0.621372736649807 mi). Such a span width was impossible with wooden poles, which were common in those days. Installing an underwater cable was considered, but for reliability reasons an overhead powerline
Overhead powerline
An overhead power line is an electric power transmission line suspended by towers or utility poles. Since most of the insulation is provided by air, overhead power lines are generally the lowest-cost method of transmission for large quantities of electric energy...
was installed, which used at the north site of the river a 68 metres (223.1 ft) tall lattice tower and at the south site one with a height of 20 metres (66 ft).