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Lake Washington Ship Canal (continued)

Seattle, WA

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Background

An aerial photograph of the Ballard Locks, numbered 1 through 9, opens this Corps of Engineers pamphlet — the caption key runs from Fishway (#1) to Superintendent's Residence (#9), suggesting a working facility that expected public visitors.

The Hiram M. Chittenden Locks — universally called the Ballard Locks — sit at the western end of the Lake Washington Ship Canal, where tidal salt water from Puget Sound meets the fresh water of Salmon Bay. The canal lifts or lowers vessels 6 to 26 feet depending on the tide, managed by two chambers: a large lock (825 feet between its gates, 80 feet wide) and a small lock (150 feet, 30 feet wide) for pleasure craft and minor commercial traffic.

Construction started August 6, 1911, and the large lock opened August 3, 1916; the small lock followed July 30. By October 1916 ships could reach Lake Union; by June 1917 they could enter Lake Washington itself, completing a navigable waterway roughly 8 miles long between the Sound and the lake. The brochure notes 227,000 cubic yards of concrete in the locks and dam — equivalent to roughly 17,000 standard ready-mix trucks.

The comparison table in the lower-left panel ranks the Lake Washington lock against seven other major North American locks:

  • Panama Canal (1,000 ft usable length, 110 ft wide) — larger in both dimensions
  • Bonneville Lock on the Columbia River (500 ft, 76 ft) — opened 1938
  • Welland Ship Canal lock (820 ft, 60 ft) — bypasses Niagara Falls between Lake Ontario and Lake Erie
  • MacArthur Lock at Sault Ste. Marie (800 ft, 80 ft) — completed July 1943

The presence of the MacArthur Lock sets the earliest possible printing date at mid-1943. The typography and production quality are consistent with U.S. government printing of the late 1940s or early 1950s.

The right panel is the pamphlet cover: the U.S. Army Corps of Engineers castle emblem centered above the publisher credit, and a schematic map tracing the canal from Shilshole Bay through the Government Locks, Lake Union, and Portage Cut into Lake Washington. Railway lift bridges are labeled by their owners — the GN Ry (Great Northern) and NP Ry (Northern Pacific) — both long since absorbed into BNSF.

Researched with claude-haiku-4-5-20251001 on May 24, 2026. AI-assisted — verify before citing.

Highlights

  • The aerial photograph, taken from above and slightly south, shows the large lock chamber on the left and the small lock to its right, with the spillway dam controlling overflow into Salmon Bay visible in the foreground.
  • The nine-item feature legend below the photo ends with 'Superintendent's Residence' (#9) — a reminder that the locks were staffed around the clock by live-in personnel.
  • The Principal Features table records the large lock's usable length as 760 feet, compared to the Panama Canal's 1,000 feet — the comparison elsewhere in this spread makes clear the Corps of Engineers was aware of the ranking.
  • The MacArthur Lock entry in the North American comparison table (800 ft × 80 ft, Sault Ste. Marie) was not completed until July 1943, fixing the earliest possible printing date.
  • The U.S. Army Corps of Engineers castle emblem is centered on the cover panel, a symbol in use since the mid-nineteenth century and still the Corps' official mark.
  • The schematic map on the cover traces the full canal corridor from Shilshole Bay to Lake Washington, labeling bridges by railway owner (GN Ry, NP Ry) alongside road bridges — a snapshot of Seattle's mid-century infrastructure layer.

Further reading