Seattle’s future as a major city began 100 years ago, with the grand opening of the Ballard Locks and the Lake Washington Ship Canal.

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SIMILAR TO OTHER grand construction projects in Seattle, such as the Denny Hill and Jackson Street regrades, the building of the locks at Ballard, during the construction of the Ship Canal, became a must-see for residents. The best spot was a viewing platform on a bluff overlooking the site on the Ballard side.

To the unnamed author of an article in Railway and Marine News, a Seattle-based trade publication, the construction at the locks symbolized the great future that lay ahead for the city: “The work being pushed is a sight worth seeing by all those public spirited men who see in every movement of the giant crane, lift of the dredge or dumping a load of earth from the steam shovel scoop, many steps nearer to the completion of this great work which will give to the port of Seattle an additional deep fresh water harbor that will have no equal in the United States.”

Editor’s note

In commemoration of the centennial of the Hiram M. Chittenden Locks and Lake Washington Ship Canal, David B. Williams and Jennifer Ott have written a history of the passageway between the lakes and Puget Sound, “Waterway: The Story of Seattle’s Locks and Ship Canal” (HistoryLink, 160 pages, $24.50). The following is a condensed excerpt from Chapter 4 of the book. Previous chapters address the geology, Native American history and decades-long battles over funding, location and design. Finally, in 1909, the U.S. Congress approved the money for a plan proposed by Chittenden, who had been commander of the Seattle District of the Army Corps of Engineers. Despite the approval, two years passed before work began on the locks, under direction of the Corps. This section of the chapter follows a discussion of the work of excavating the canals from Portage Bay to Union Bay and from Lake Union to Salmon Bay, which had been funded by King County and Washington state.

Work on the locks began in August 1911. The first task was to build a temporary dam, called a cofferdam. Made of wood piles and walls that sandwiched fine clay, the cofferdam ran for about 2,300 feet in a giant “C” around the locks’ site. By early August 1912, the waterproof cofferdam was built and the pit within dredged and pumped free of water. Next came construction of a wooden trestle down the center of the pit, followed by the erection of two gantry cranes that spanned the worksite and facilitated movement of heavy loads, particularly concrete. South of the dam was the temporary channel that had been dredged to allow water and boats to move in and out of Salmon Bay.

Concrete pouring for the locks structure began in February 1913, with most of the work completed in 13 months. The walls are not completely solid, as two culverts run the length of each of the locks. These conduits facilitate the filling of the lock chambers; water enters at the upper end, or the Salmon Bay side of the culvert, and flows into the locks via drains on each side of the chamber.

Before the concrete work was completed, workers had begun to install the gates within the locks. The locks required nine gates — three sets operating in the large lock and two in the smaller lock — plus one set of guard gates located at each end of each of the locks. Known as mitering gates, so called because the doors, or leaves, meet at an angle facing upstream and resemble a miter joint, each door is hollow and consists of a series of stacked layers of steel framing surrounded by a waterproof skin, also of steel. Within each leaf are buoyancy chambers, which help relieve the weight of the doors in the water. The tallest doors are 55 feet high and weigh 480,000 pounds.

WITH THE GATES in place and concrete work completed, workers could now turn to the next stage of the project: connecting freshwater and saltwater. Maj. James Cavanaugh, the new Army Corps of Engineers’ district commander, started the process on a cold Feb. 2, 1916, by allowing water to flow into the larger lock. Thirty-two minutes later, the big chamber was filled, the gates were opened, and the main lock became the channel for water and boats to move between Puget Sound and Salmon Bay.

Now that the locks were open, workers began to build a new cofferdam south of the locks in the temporary channel that had been excavated between Salmon Bay and Shilshole Bay. The cofferdam would enclose the area where the overflow, or spillway dam, was to be built. It would be 235 feet wide with six gates, known as Tainter gates, each of which resembles a piece of pie with the round end facing upstream. The gates operate independently and were a standard design used, and still used, on waterways across the country.

The main job of the dam was to allow excess water to flow out of Salmon Bay, which would help keep the bay, Lake Union and Lake Washington at an elevation of 20 to 22 feet above sea level. (Lake Washington had originally been 29 feet above sea level.) Workers completed the spillway in a little more than three months. The lock gates remained open throughout the entire work on the spillway.

On July 12, 1916, at 6 a.m., when the gates of the locks closed, Salmon Bay ceased to be a tidal inlet. No longer would saltwater fill the bay twice a day at high tide. No longer would the lumber mills of Ballard have to wait until the tide came in to move their logs. Although The Seattle Times reported that the closing of the gates was “an event fraught with vital importance to Seattle and one that probably will be a large factor in this city’s future destinies,” there “was no cheering, no excitement” to mark the occasion. The Corps simply closed the gates at low tide without any formal ceremony.

They also started to release water from behind a dam at the outlet of Lake Union, which began the process of turning Salmon Bay into a freshwater reservoir. Almost three weeks later, Salmon Bay was filled with enough water to allow boats to move through the locks from saltwater to freshwater. The official opening occurred at 10 a.m. on Aug. 3, 1916, when the snag steamer the Swinomish, accompanied by the Orcas, traveled through the larger lock.


Boat Parade: July 9, 11 a.m. to 2 p.m. A flotilla of boats and ships will parade from the Ballard Locks into Lake Union in commemoration of the centennial of the Ship Canal opening. The Centennial Boat Parade will roughly re-create the original parade that marked the official opening on July 4, 1917. Storied vessels such as the S/V Adventuress, the yachts Honey Boy and Glory Be, the Virginia V, the halibut schooner Tordenskjold and others will participate.

Book launch: July 12, 7 p.m., Museum of History & Industry. On July 4, 1917, amid much fanfare and after more than 60 years of planning, the Lake Washington Ship Canal opened to the public. Join co-authors Jennifer Ott ( historian) and David B. Williams (author of “Seattle Walks”) as they share stories from their new book, “Waterway: The Story of Seattle’s Locks and Ship Canal.” Learn how industry, transportation, and the very character of the city and surrounding region developed in response to the economic and environmental changes brought about by Seattle’s canal and locks. Cost: $10 for MOHAI members, $15 for nonmembers.

Book reading: July 23, 3 p.m., Seattle Public Library (Central Branch). Free.

A crowd of 2,500 standing on either side of the locks began cheering and clapping as the boats, filled with dignitaries and their wives, passed by. After dropping from the new level of Salmon Bay down to the sea level of Puget Sound, the boats exited, circled about Shilshole Bay, re-entered the locks and returned to freshwater. The two steamers then proceeded up to the Ballard Bridge before returning to the locks.

WITHIN DAYS, 150 freight and passenger boats, 30 scows and 14 log rafts had passed through the locks. They could not yet proceed into Lake Union because of the dam at the head of the Fremont Cut. Workers had started to remove it on Aug. 5, but boats would have to wait until it was gone before they could complete the trip to Lake Union.

Finally, on Friday, Aug. 25, the Corps began the long-awaited “union of the waters” of Lake Union and Lake Washington, as the Seattle Post-Intelligencer dubbed the event. At 2 p.m., workmen with shovels opened up a small cut in the cofferdam built at the west end of the Montlake Cut. The stream quickly turned into a raging torrent, causing the crowds on the cofferdam to flee the water, dirt and huge timbers that had comprised the rapidly disintegrating cofferdam. In exactly 56 minutes, 45 million gallons of water from Lake Union had filled the cut, followed by a small skiff carrying a man and two boys, which motored through the opening in the cofferdam and into the cut.

Three days later, after crews had cleaned out the debris in the cut, the Corps opened gates at the eastern end of the Montlake Cut and began to lower Lake Washington. The plan was to let the water out slowly in order to not damage either houseboats around the lakes or the Fremont Cut and the locks. Lake Washington dropped 2 feet in the first week and 4 feet in the first month. After that, it dropped up to 2 inches a day.

By late October, Lake Washington had lowered 9 feet and was equal in elevation to Lake Union and Salmon Bay, but boats were not immediately allowed to pass through. Crews still had to remove the gates that separated Union Bay from the canal, as well as sediment and debris that had accumulated at either end of the Montlake Cut. This was soon completed, and small boats finally began to move freely between Lake Union and Lake Washington.


THE P-I REPORTED that more than half of the city’s population of 360,000 gathered for the grand opening of the canal on July 4, 1917. They ringed the shores of Salmon Bay, the cuts, Lake Union and the west side of Lake Washington. Others headed out on the water, sailing, paddling, steaming and motoring, attending events from the locks to Leschi Park, where a great line of boats paraded by the crowds. Led by the Roosevelt, the flotilla traveled through the large lock into Puget Sound, then returned to Shilshole Bay, where the Roosevelt tied to the locks and served as an open-air stage for the speakers.

After a quick tour around Lake Union, the Roosevelt traveled into the Montlake Cut and through a blanket of flowers floating on the water. Finally, at 4:25 p.m., she reached Leschi Park, followed by a line of more than 200 boats that stretched back to Montlake. The Roosevelt then returned to Salmon Bay, and the festivities were over.

In its evening edition on July 4, The Seattle Times summed up the views of the city:

It was a gay day of fanfare. Seattle did both itself and the canal proud. The noise and clamor and pictorial features that unceasingly marked the hours were but the outward manifestation of the tremendous significance of the occasion, a significance that every thinking person on the whole canal right of way realized in full — that here, completed, ready for use, actually in use, was a thing that will do more toward bringing Seattle its destined million inhabitants and undisputed Pacific Coast supremacy than any other factor the city has ever known or is likely to know in the present generation.