Sutro Tower

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Sutro Tower as viewed from the east

Sutro Tower is a three-pronged antenna tower on Mount Sutro in the western part of San Francisco, California. It is a dominant part of the city skyline, and a useful landmark for locals. However, strong local opposition and criticism was directed towards the tower even before it was completed. The two main controversies surrounding the construction of Sutro Tower were local politics and the aesthetic effect the tower would have on the rest of San Francisco. San Francisco writer Herb Caen once said, “I keep waiting for it to stalk down the hill and attack the Golden Gate Bridge.”^[1]

1 Reasons for the tower
2 Construction
3 Views
4 References
5 External links

[edit] Reasons for the tower

Before its construction, television reception in San Francisco was quite spotty, as the many hills of the city would block the line-of-sight radio waves — this was before the rise in popularity of cable television. Before Sutro Tower, transmitters were scattered throughout the Bay Area, including at San Bruno Mountain, Mt. Allison, Monument Peak, and Mt. Diablo. Reception outside of San Francisco was incrementally improved by the tower. By having all the main Bay Area television stations in one location, reception was improved by allowing all receiving antennas to be pointed at one tower instead of many. However, local NBC affiliate KNTV, which originally broadcast from Loma Prieta Peak in Santa Clara County, currently broadcasts from San Bruno Mountain. Most residents in San Mateo County, the East Bay, and Marin County can aim their antennas in the general direction of Sutro Tower and get all stations, including KNTV. Some residents in San Francisco need to rotate their antenna, as San Bruno Mountain is approximately five miles south of Sutro Tower.

[edit] Construction

Construction began in 1971, by Kline Tower of Columbia, South Carolina, and was completed in 1973, with the first transmissions from Sutro Tower on July 4, 1973. About 15 million pounds (6,800 tonnes) of concrete were used to make the foundation of the 3.7 million pound (1,700 tonne) tower. Earthquake proofing includes ballasting two thirds of the weight of the structure below ground, resulting in a center of gravity at sixteen feet below ground level. It is used to transmit ten analog, eleven digital TV stations and four FM radio stations to the San Francisco Bay area. The tower is owned by Sutro Tower, Inc., which in turn is owned by four television stations KTVU, KRON, KPIX and KGO-TV, with usage leased to other Bay Area TV and radio stations.

Named after Adolph Sutro, a businessman and former mayor of San Francisco who had a mansion located about 100 feet away from where the tower is now located, the tower stands 977 feet (298 metres) from the ground and 1,800 ft (549 m) from sea level. It is the tallest structure in the city, surpassing the 853 ft (260 m) Transamerica Pyramid by more than 100 ft (30 m). In addition, it is built on one of the highest peaks in the city, the old site of the Sutro Mansion owned by Adolph Sutro's descendants.

The original design of the tower called for white lights longitudinally rising along its four legs to its top. When opened, these lights were lit. However local resistance and esthetic considerations forced the operators to turn off the lights and they have never been used since.^{[citation needed]}

[edit] Views

Sutro Tower in fog

The facility is surrounded by a fence and the site offers no panoramic viewpoints of San Francisco, but there is a platform near the top of the tower, 762 ft (232 m) above ground. Access for authorized maintenance workers is by a tiny two-person elevator that runs inside the west tower enclosed leg.

On a clear day, the tower can be seen from the East Bay peak of Mount Diablo and is sometimes the only part of San Francisco seen above the coastal fog when it is blown inland, typically on summer mornings and evenings.

Sutro Tower is restricted to authorized personnel and stands on private property. The tower may be viewed up close from La Avanzada Drive.