Engineering Reports, 1936-1967

Overview of the Collection

Seattle (Wash.). Lighting Dept.; Seattle City Light; Strandberg, H.V.
Engineering Reports
1936-1967 (inclusive)
0.8 cubic feet, (2 boxes)
Collection Number
Engineering reports regarding power transmission and distribution.
Seattle Municipal Archives
Seattle Municipal Archives
Office of the City Clerk
City of Seattle
PO Box 94728
Seattle, WA
Telephone: 2062337807
Fax: 2063869025
Access Restrictions

Records are open to the public.


Historical NoteReturn to Top

City Light provides electricity and electrical and conservation services to its public and private customers. It is the largest public utility in the Pacific Northwest. Public responsibility for electrical energy dates back to 1890 with creation of the Department of Lighting and Water Works. The formulation of this public utility stemmed from fear of monopolization by private companies and was reinforced by the inadequacy of those companies during the Great Fire of 1889. Unable to gain access to private water, much of the business district was burned to the ground. Citizens responded eagerly to the idea of publicly owned water and electricity, which was later encouraged as part of President Roosevelt's New Deal in the 1930s.

In 1902, Seattle voters passed a bond issue to develop hydroelectric power on the Cedar River under the administration of the Water Department. This was the nation's first municipally owned hydroelectric project. Electricity from this development began to serve customers in Seattle in 1905. A City Charter amendment in 1910 created the Lighting Department, making it a full member of the City's Board of Public Works. Under the leadership of Superintendent James D. Ross, the department developed the Skagit River hydroelectric project which began supplying power in 1924 with the completion of the Gorge Dam.

Both public and private power was supplied to Seattle until 1951 when the City purchased the local private electrical power company, the Puget Sound Power and Light Company, making the Lighting Department the sole supplier. The Boundary Project in northeastern Washington began operations in 1967 and supplied over half of City Light's power generation.

The current name of the agency was adopted in 1978 when the department was reorganized. As a municipally owned public power system, Seattle City Light is governed by elected Seattle officials. Administrative authority rests with the Superintendent and an executive team that includes the department's Chief of Staff, Service and Energy Delivery Officer, Human Resources Officer, Power Supply and Environmental Affairs Officer, and Chief Financial Officer. City Light is responsible for electrical service and streetlight service, streetlight problems, and also conservation, both residential and commercial/industrial.

City Light provides low-cost, reliable, and environmentally responsible electric power to approximately 395,000 customers in Seattle and neighboring areas, including Burien, Lake Forest Park, Normandy Park, Renton, SeaTac, Shoreline, Tukwila, and unincorporated King County. It is the ninth-largest public power system in the United States and has the lowest rates among comparably sized cities in the United States.

Content DescriptionReturn to Top

Documents generated for the City of Seattle Lighting Department regarding power transmission, distribution, load forecasting, cost savings, and testing in the Seattle and Skagit areas. Includes reports, charts, calculations, drawings, blueprints, and photographs.

Use of the CollectionReturn to Top

Preferred Citation

[Item and date], Engineering Reports, Record Series 1209-03. Box [number], Folder [number]. Seattle Municipal Archives.

Administrative InformationReturn to Top

Detailed Description of the CollectionReturn to Top

Container(s) Description Dates
Box Folder
1 1 Skagit Operating Conditions undated
1 2 The Cross Catenary Type of Construction as Applied to Skagit Transmission Line No. 2 1936-1937
1 3 Skagit Transmission Lines #2: Type A and Type B Tower Tests at Pittsburgh 1937
1 4 West Michigan St. Crossing Towers 1946-1958
1 5 3rd Ave. NW Crossing Towers 1938-1957
1 6 6th NE (Lake Union) 1938-1951
1 7 West Waterway Crossing 1951-1968
1 8 Special Tower, D.C. Transmission 1938
1 9 Steel Towers for Skagit Transmission Line No. 2 1951
1 10 Report and Estimate of Cost of Transmission Lines and Substations to Feed Bellingham, Sedro Woolley, Burlington, Everett, Mt. Vernon, and Snohomish From Skagit Project 1938
1 11 Ground Resistance, Skagit Transmission Line No. 2 1939
1 12 Relocation of Newhalem-Skagit Crossing of Skagit Transmission Line #2 1937
1 13 Calculation of Temperature Tension Stringing Charts: Method Used 1936
1 14 Memorandum Report of Inspection of Crossing Towers 1939
1 15 Inspection and Recommendations Relating to the Protection of Diablo Power House from Falling Rock 1939
1 16 Physical and Electrical Characteristics of City of Seattle Lighting Department's Transmission Lines undated
1 17 Index of Engineering Department Drawings for Gorge Transmission Line 1932
1 18 Accidental Transmission Line Outages 1924-1939
1 19 Tacoma Tie Line - Estimated Cost to Rebuild For 110-kv Operation 1940
1 20 North End Warehouse - Economics 1941
1 21 Performance of Skagit Generators and Transmission Lines 1942
1 22 An Analysis of Outage Data 1953
1 23 Dielectric Test Ross Generator 1953
1 24 A Study of Load Trend in the Central Business District and Recommendations for Future Supply Facilities 1953
1 25 A Test of the Efficacy of the Phase-Shifting Transformers at Broad Street in Transferring Load Normally Fed From South Substation 1953
1 26 Relative Cost of Aluminum Versus Steel 26 KV Bus Structures at Duwamish Sub 1953
1 27 A Load Forecast for the Seattle Area Based on Population and Use Trends 1954
1 28 A Twenty Year Forecast of Seattle City Light Construction Fund Requirements 1954
2 1 An Economic Study of 13KV Versus 4KV as a Distribution Voltage in the Northern Part of the Underground District 1954
2 2 Reactive Power Requirements of the Seattle System 1954-1957
2 3 A Survey of the Service Facilities in the Seattle Area Engineering Report #188
ER 188
2 4 Index Test of Gorge and Diablo Plants 1943-1944
2 5 Transformer Current Interruption By Air-Break Disconnecting Switch 1955
2 6 Fremont Distribution Substation Sound Level and Frequency Tests 1955
2 7 A Fault and Load Distribution Study of the Boeing 13-KV Network 1955
2 8 Canal Substation 55-KV to 13-KV Transformer Capacity 1955
2 9 Domestic Water Heater Study 1955
2 10 Reprocessing Insulating Oils 1955
2 11 Automatic Operation Study of the Cedar Falls Generating Plant
Engeineering Report No 198 Project No 996 by K E Walters
2 12 Bushing Testing by the Radio Influence Voltage Method undated
2 13 Residential Load Study City of Seattle Department of Lighting 1954-1955
2 14 Preliminary Investigation of the Moving Steel Towers and Power Lines to Clear for the Construction of the 6th Avenue N.E. High-Level Bridge 1957
2 15 Thirty Years Experience with Wood-Pole Transmission-Line Construction 1954
2 16 Study of 26 KV Versus 4 KV Primary Distribution System 1961
2 17 Gound Fault Test Results on Allis Chalmers Oil Circuit Breaker (Type FZO-50-34F) 1962-1963
2 18 Testing of Transformer Cluster Mount Brackets by Contract Construction Division 1963
2 19 An Analysis of the Cooling Air Flow Through a Large Electrical Generator 1963
2 20 History 34.5 KV Oil Circuit Breaker Failures 1963
2 21 Inspection of Portion of Legs of Steel Transmission Towers Below Ground Surface 1964
2 22 Testing of Aluminum Luminaire Support Brackets 1965
2 23 Tests of Joints in Wood Power Poles Cemented with Epoxy Resin Glues 1967
2 24 A Long-Term Load Estimate for the Advance Program 1956
2 25 Test Spraying of Weedecide on Skagit Transmission Line Right of Way 1946

Names and SubjectsReturn to Top

Subject Terms

  • Electric utilities--Washington (State)--Seattle
  • Electric power distribution--Washington (State)
  • Electric power transmission--Washington (State)

Geographical Names

  • Seattle (Wash.)
  • Skagit County (Wash.)