Hiram M. Chittenden Locks and Lake Washington Ship Canal

At 3015 NW 54th Street in Ballard, a walkway runs across the Lake Washington Ship Canal on top of the locks. To the east lies Salmon Bay, fresh water held at a steady height. To the west is Shilshole Bay of Puget Sound, rising and falling with the tide. The historical marker on the grounds puts the difference between the two at 6 to 25 feet, depending on the tide. The Corps of Engineers master plan gives the lift as 6 to 20 feet. A boat enters a chamber and the miter gates close behind it. The lockmaster in the control tower then opens valves, and water moves through tunnels in the walls until the boat floats level with the far side. The marker calls the arrangement “a boat elevator.” No pumps are used. Gravity moves the water, about 7.5 million gallons of fresh water for an average filling of the large lock.

The pages call these the busiest locks in the nation, passing up to 50,000 vessels a year. Passage is free. Emergency and commercial vessels go first. The U.S. Army Corps of Engineers built the locks and has run them for more than a century, and the grounds are free to enter. The pages also give the attendance two ways: a 2017 resolution of the Washington House counted more than 1.2 million visitors a year, and the Seattle Times in 2023 counted more than 2 million.

Two chambers and a crew

The locks are two chambers, side by side. The large lock measures 825 feet between its upper and lower miter gates and 80 feet wide, and an intermediate gate can divide it in two. The locks’ boater page says it takes vessels up to 760 feet long. The small lock, just south of it, is 150 feet by 30. Its floating mooring bitts ride up and down the walls, which makes it the easier of the two to tie up in. Jet skis, kayaks and every other unpowered craft must use the small lock. Paddleboards are allowed in neither. The boater page warns that a busy summer weekend “can be quite intimidating.”

On a sunny August day in 2023, a Seattle Times writer watched crowds gather while a 120-foot motor yacht slid out of the large lock with a matching SUV on its deck. A group of grade-school boys pushed their bikes across the walkway to the far bank. The largest crew at the locks guides the boats: they shout directions, handle lines and staff the tower. Mike Hand, lock master and a 14-year veteran, has seen boats sink in the chambers and a tug misjudge its beam and get stuck. People fall overboard. Two kayakers were once swept over the spillway and survived. One tug pushing a gravel barge lost throttle control, and the crew worked the lines until the barge struck the gate. “They slowed it just enough that it only made a small dent,” Hand said.

Much of the machinery is old. Under the administration building a circular stair with a brass railing leads down to the original pump motors of 1917, kept now for their historic value. Five stories down, a tunnel carries utility lines beneath the locks. “We’ve got about 55 feet of water over us here,” said David Chapman, the project engineer. Near the small lock, gears the size of a truck tire are greased several times a week. Chapman said he “kind of hate[s] to see them go,” because “there’s something almost romantic about these old mechanical things.”

As the centennial approached, inspectors cut the locks’ safety rating from 4 to 2 on a scale of 5. A 2017 study commissioned by business and community leaders found up to $60 million in needed repairs. By 2023 the Corps had spent or committed more than $65 million, including $18 million for new center gates in the large lock. Each of those hollow gates weighs nearly half a million pounds.

The Corps’ greatest concern is an earthquake that leaves the gates unable to close. Richard Smith, the Corps’ dam safety manager, says Lake Washington could then drop 20 feet in four days. A new crane at the large lock can lower steel bulkheads to stop the outflow.

The repair work continues. The Corps announced that the large lock would close from November 2 to November 20, 2026, for annual maintenance. The small lock was scheduled to close from December 7, 2026, to January 18, 2027, for installation of an Emergency Closure System.

Salmon at the windows

At the south end of the spillway dam, six steel radial gates span 235 feet. Beside them a fish ladder carries salmon around the locks. Indoor windows look into the ladder underwater. The locks’ site gives the season by species:

• Sockeye: best mid-June to mid-July. The runs have fallen sharply, to a recent average under 20,000 a year.
• Chinook: best in August, about 15,000 a year. Visit Ballard narrows the peak to mid to late August.
• Coho: best in September, about 25,000 a year.
• Steelhead: pass from November to May, most often seen from late February to early April.

The site also warns that a visitor may see no salmon at all, even at the peak, because of low tides or hot weather. Seals feed on the salmon below the locks, and herons wait at the edges. The 1970s ladder has no way to keep out seals and sea lions, and some settle inside it to feed.

A fish ladder was built here in 1917. The American Society of Civil Engineers counts it among the first in the United States. Rebuilding began in 1973, and the reconstruction of 1976 added the viewing room. The Salmon Education Center beside it was renovated with public donations.

Young salmon leaving for the sea face other hazards. Since the mid-1990s it had been known that the corroded valves of the large lock, stuck on high speed, were drawing outbound smolts into barnacle-crusted culverts. “It was essentially like a cheese grater,” said Jason Mulvihill-Kuntz of the Lake Washington/Cedar/Sammamish Salmon Recovery Council. These valves are called Stoney gates, after the Irish engineer who invented them, and were first used in the Panama Canal. The Corps replaced them for $13 million. Mike Mahovlich of the Muckleshoot Tribe said the new adjustable valves should be safer, but that it took until 2021 to fix a threat known for more than a quarter century.

Warm water is a growing danger. Temperatures in the canal sometimes pass 70 degrees, and in recent years more than half of the adult sockeye that climbed the ladder died before spawning. The Muckleshoot have taken to catching sockeye at the ladder and carrying them by boat to a hatchery on the Cedar River. “The only way to really fix it is to take them completely out, and that’s not going to happen,” said Rob Purser, fisheries director for the Suquamish Tribe.

Carl English’s garden and the blacksmith shop

North of the locks, the ground rises to a plateau 45 feet high. On it stands the Lockkeeper’s House of 1913, the first permanent building on the reservation. In 1967 it became the residence of the Seattle District Engineer and was renamed for Colonel James B. Cavanaugh. Below it, a terraced bank of dredge spoils steps down toward the water in 5-foot drops. ASCE notes that dredge material was used as fill for the garden.

That garden covers about seven acres and holds more than 500 species of trees and plants. Carl S. English, Jr., a horticulturist and botanist, was hired by the Corps in 1931. Over more than forty years he made the ground into a garden in the English estate style. He also helped plant the banks of the Fremont and Montlake Cuts. Along the Fremont Cut, rows of Lombardy poplars run almost unbroken from the Northern Pacific Railway Bridge to the Fremont Drawbridge. The National Register nomination repeats a description of them as “colonnades.”

On weekends from Memorial Day to Labor Day, the garden holds free concerts. Listeners bring picnics onto the lawn. Donations are suggested, and all of them go to volunteer performances, garden upkeep and education programs. The garden is also rented for weddings, and dogs are welcome on a leash.

East of the plateau, the architects Bebb and Gould laid out a cluster of classical concrete buildings around a courtyard that opens onto the locks. The administration building of 1914–15 is the center of the group. The visitor center stands near the east gate, in a building that began as the blacksmith shop where repair parts for the locks were made. The nomination dates the concrete carpenter and blacksmith shops to about 1921. Today its main floor holds a gift shop and a theater that shows short films on request. Exhibits on the locks and on the Corps in the Northwest fill the second floor.

The staff numbers 64, including full-time gardeners and biologists. Rangers lead the tours and answer “Where’s the bathroom?” dozens of times a day. Free tours start at 2:00 pm and run about an hour; Recreation.gov lists them May 1 through September 30. The locks’ own site says weekend tours were canceled for lack of staff.

Sixty-three years from a picnic to a parade

The canal began as a suggestion at a Fourth of July picnic. On July 4, 1854, the pioneer Thomas Mercer proposed the name Lake Union for the fresh lake north of town. Native people had called it “small lake” in Lushootseed for centuries. Mercer and others expected it to become part of a water route between Puget Sound and Lake Washington.

Other routes were tried and dropped. Soil was moved at the north end of Beacon Hill to join Lake Washington directly to Elliott Bay, and a cut from Lake Union to Smith Cove was considered. In 1890 Congress made its first appropriation for the project. On December 15, 1891, a government survey favored the present route from Shilshole Bay. In 1906 Congress authorized a privately financed canal proposed by James A. Moore, with a single timber lock at Salmon Bay.

The same year, the Corps sent Hiram Martin Chittenden to head its Seattle District. He was a West Point graduate and the author of histories of Yellowstone and the western fur trade. He arrived already gravely ill from overwork and lingering typhoid. In December 1906 he recommended a double masonry lock. ASCE credits him with choosing concrete over wood and with insisting on two locks of different sizes. His plan also lowered Lake Washington, which ended the regular flooding of nearby rivers. The state appropriated $250,000 in early 1909. In June 1910 Congress put up $2,275,000, on condition that the other cuts along the route be paid for locally. Chittenden retired that year, paralyzed below the waist. In 1911 King County voters elected him a founding commissioner of the Port of Seattle.

Construction began in September 1911 under Colonel Cavanaugh, with Arthur W. Sargent as assistant engineer in charge. Ground was broken on November 10, 1911. The first concrete went into the forms in February 1913. The mix was one part portland cement, three parts sand and six parts gravel, and the locks were built without piles on a bed of hard clay.

The sources disagree on when the gates first closed and Salmon Bay began to turn from salt water to fresh. The 2017 House resolution gives July 1912. The National Register nomination gives July 12, 1916.

The first boat passed through on August 3, 1916. On August 25, workers cut a gap in the cofferdam at the Montlake Cut. Water fell 37 feet, and 45 million gallons ran from Lake Union into the cut in 56 minutes. That autumn the dam at the east end came out, and over the following months Lake Washington dropped nine feet. Before the canal, coal from inland mines had been handled 11 times on its way to Seattle. Afterward the city’s 4½ miles of harbor grew to 100 miles of piers and wharves.

Dedication waited for the Fremont Bridge, finished in mid-June 1917. On July 4, 1917, the steamer Roosevelt led a parade of more than 200 boats through the locks, and an early Boeing aircraft flew overhead. The marker calls her the USS Roosevelt, flagship of Robert Peary’s 1909 expedition to the North Pole. The nomination names her the flagship of “Commodore Robert E. Perry’s Arctic Expedition of 1907.” The marker adds that the locks were then the largest navigation facility in North America. Chittenden died that autumn, at 58.

The project was declared complete in 1934. The hoped-for Navy base went to Bremerton instead, and by the 1960s pleasure boats outnumbered commercial ones. The North Pacific Fishing Fleet still sails from Fishermen’s Terminal on Salmon Bay and passes through the locks on its way to sea and home again.

The Black River and the namesake

Locally the locks were the Government Locks, or the Ballard Locks. Congress named them for Chittenden in 1956. A 1973 biography by Gordon B. Dodds, drawn from Chittenden’s diaries and papers, quotes him calling the removal of Native Americans “the decree of destiny.”

When the locks’ centennial came in 2017, Michael Herschensohn of the Queen Anne Historical Society called the events a commemoration rather than a celebration. “If we hadn’t had the centennial, there’s an awful lot we wouldn’t have thought about,” he said. Jim Ryan, a retired Corps employee who volunteers at the locks, said: “I personally don’t think he was better or worse than anybody else in the timeframe.”

When the locks opened, Salmon Bay rose a few feet and pushed out the homes, businesses and Native camps along its edge. At the south end of Lake Washington, the Black River had drained the lake toward the Duwamish River. When the lake fell, the river dried up. James Rasmussen, a Duwamish Tribal member, tells the story of an ancestor who lived at the Duwamish village on its bank in the autumn of 1916. “’I look down at my canoe landing, and it’s dry,’” Rasmussen said, repeating his ancestor’s words. “’There are pools of water where there was a river, and salmon are trapped. The mostly white people are bringing gunnysacks to pull up the salmon and they’re having a great old time.’”

Early plans had included a second lock between Lake Washington and Lake Union. It would have held the big lake at its natural level, and the Black River would have kept running. The historian Feliks Banel judged it probably impossible to say whether Chittenden dropped that lock because of his views or because it saved money. Duwamish Tribal chair Cecile Hansen says the canal “erased” the village. An excavation there in 1980 found artifacts and the post marks of at least one large longhouse. The Renton Shopping Center now stands on the site, near the corner of Rainier Avenue and Sunset.