Hoover Dam, Static Towers & Lines, U.S. Highway 93, Boulder City

Source document Quoted word for word from HAER NV-27-G. Not written, edited or summarised by this site.

U.S. Highway 93 C e Vicinity of Boulder City Clark County Nevada USGS Hoover Dam, Nevada-Arizona 7.5 Minute Provisional UTM Coordinates: l (Tower 1) 1 (Tower 2) 1 (Anchor 3) 1 (Tower 4) 1 (Tower 5) Date of Construction: Engineer: U.S. Bureau of Reclamation Builder: U.S. Bureau of Reclamation U.S. Highway 93 Vicinity of Boulder City Clark County Nevada USGS Hoover Dam, Nevada-Arizona 7.5 Minute Provisional UTM Coordinates: l l (Tower 1) l (Tower 2) (Tower 3) l (Tower 4) (Tower 5) Statement of

Source document Quoted word for word from HAER NV-27-G. Not written, edited or summarised by this site.

The static tower system was constructed as an integral part of the control and protection system for the Hoover Dam switchyard complex, to protect the switchyards and transformer circuits from lightning strikes. Report Prepared by: Associated Cultural Resource Experts (ACRE) Sangre de Cristo Road, STE 202 Littleton, CO Date: April HISTORIC AMERICAN ENGINEERNG RECORD HOOVER DAM, STATIC TOWERS AND LINES HAER NO. (Page 2) The static tower system was constructed as an integral part of the control and protection system for the Hoover Dam switchyard complex, to protect the switch yards and transformer circuits from lightning strikes. Description: The static protection system consists of four steel towers up to above ground level, with cables between the towers.

The towers are located on high topographic points generally to the east and west of the City of Los Angeles Switchyard, and heavy steel cables are strung between the towers. The towers consist oflegs that support a level 36'-square base, a straight tower section in some towers, and then a battered tower section. Near the top of the battered section is a service platform. The four steel static towers are designated and D-5 (D for diverter). Towers and D-5 have identical battered, lattice-steel towers and steel leg sections below the main tower that vary according to the topography of the respective tower location. Tower D-2 also had a 36' -high, square, vertical frame section between the battered tower section and the legs.

Towers and D-5 were constructed with a service platform near the top, and steel cables between towers were hung below the service platform. Tower D-1 has a vertical frame section identical to that of Tower a "standard-batter" section, and a "special batter" section. Tower D-1 was built with two service platforms near the top, to receive two steel cables from Towers D-2 and From Tower the steel cables descended to concrete anchors embedded in the ground. Steel cables from Towers D-2 and D-4 extended eastward to concrete anchor D-3 embedded in the Arizona canyon wall.

A cable also connected Towers D-2 and History: The static diverter system was built in to protect the switchyard complex, particularly the City of Los Angeles Switchyard, relay house, and control cable tunnel hoist house, from lightning strikes. The static towers and cables do not appear to have been altered since construction.

Source document Quoted word for word from HAER NV-27-G. Not written, edited or summarised by this site.

This documentation of features of Hoover Dam and associated structures was accomplished by Associated Cultural Resource Experts (ACRE). ACRE completed documentation of21 features in October Documentation on four linear features was extended and an additional 3 features were newly documented in February Both phases of documentation were conducted as part of the historical/engineering recordation of Hoover Dam-prepared for the Department of Energy, Western Area Power Administration; Bureau of Reclamation; and Federal Highway Administration-that includes a narrative for the Addendum to Hoover Dam and individual documentation of 25 features located at the Hoover Dam facility, photo documentation, and documentation of existing historic photographs and site plans.

The recordation conforms to the standards of the Historic American Engineering Record, U.S. Department of the Interior. Other reports in the HAER collection completed for these projects are a narrative for the Addendum to HOOVER DAM, STATIC TOWERS AND LINES HAER NO.

(Page 3) Hoover Dam and 24 short forms for individual structures: Hoover Dam, Los Angeles Switchyard (NV-27-A); Hoover Dam, Southern Sierras/CEP/Southern California Edison Switchyard Hoover Dam, Metropolitan Water District Switchyard Hoover Dam, State of Nevada Switchyard Hoover Dam, Southern California Edison Switchyard (NV-27-E); Hoover Dam, Arizona-Nevada Switchyard Hoover Dam, Static Towers and Lines Hoover Dam, Los Angeles Relay Control Building Hoover Dam, Switchyard Fire House (NV-27-I); Hoover Dam, Promontory Water Tank Hoover Dam, Control Cable Hoist House Hoover Dam, Transformer Circuits Hoover Dam, Los Angeles BPL Lines 1-3 Hoover Dam, Southern California Edison North and South Lines Hoover Dam, Hoover-Basic Magnesium North and South Lines Hoover Dam, Metropolitan Water District Line 1 Hoover Dam, United States Construction Railroad Hoover Dam, U.S.

Highway 93 Nevada Segment Hoover Dam, Lower Portal Access Road Hoover Dam, Kingman Switchyard Hoover Dam, U.S. Highway 93 Arizona Segment (NV-27-U); Hoover Dam, Explosives Magazines Hoover Dam, Nevada Downstream Waste Tailings and Hoover Dam, Nevada Spoils Tunnel Hoover Dam, Henderson-Mead Transmission Line 2

Source document Quoted word for word from HAER NV-27-G. Not written, edited or summarised by this site.

This documentation was prepared for three federal agencies: U.S. Department of Transportation, Federal Highway Administration (FHWA), Central Federal Lands Highway Division, Lakewood, CO; U.S. Department of Energy, Western Area Power Administration (Western), Desert Southwest Customer Support Region, Phoenix, AZ; and U.S. Department of Interior, Bureau of Reclamation (Reclamation), Lower Colorado Region, Boulder City, NV. This documentation records certain transportation and electrical features associated with Hoover Dam before planned removal or alteration of some structures. FHWA plans to construct a bridge over the Black Canyon of the Colorado River about downstream from Hoover Dam. The Hoover Dam Bypass Project would include realignment of U.S.

Highway 93 on the Nevada and Arizona sides of Black Canyon. The project would include demolition, relocation, or substantial visual impact to a segment of U.S. Highway 93 on the Nevada approach to Hoover Dam, a segment of a former alignment of U.S. Highway 93 in Arizona, electrical transformer circuits in Arizona and Nevada, two electrical switchyards, a segment of the grade of the U.S. Construction Railroad, a stone gate structure for a dam construction and operations road, and six historic transmission lines. This documentation also records certain structures not directly affected by FHWA's Hoover Dam Bypass Project. Electrical transmission facilities at Hoover Dam are administered by Western, but these facilities are within a federal reservation administered by Reclamation.

Documentation of electrical structures is intended to partially fulfill responsibilities of Western and Reclamation under Section 110 of the National Historic Preservation Act (As amended). Some electrical structures addressed by Western and Reclamation would be directly affected by FHWA's Hoover Dam Bypass Project, and all structures addressed by Western and Reclamation are functionally related and geographically near structures addressed by FHWA. Project Manager and historian for the recordation was Kurt P. Schweigert of Associated Cultural Resource Experts. The photographers were Deborah Dobson-Brown and Douglas M. Edwards of Associated Cultural Resource Experts.

This documentation was prepared on the basis of research conducted at Reclamation archives in Denver, CO, and Boulder City, NV; Western archives and files in Denver and Phoenix, AZ; the National Archives and Records Administration in Denver; libraries of the University of Nevada-Las Vegas; and the Western History Collection of the Denver Public Library. This documentation includes information contained in survey reports for the Hoover Dam Bypass Project Environmental Impact Statement, an evaluation of the Western switchyards at Hoover Dam, an evaluation of the Hoover Dam construction railroads, a National Register nomination for Hoover Dam, and other documents. HOOVER DAM, STATIC TOWERS AND LINES HAER NO. (Page 4)