Changing the course of Lake Washington

As early as 1854 there had been talk of building a navigable connection between the two bodies of water. 13 years later the U.S. Navy gave its endorsement to this idea, with a view to possibly building the Puget Sound Naval Shipyard on Lake Washington, but nothing was built in time to prevent their placing it at Bremerton, on the other side of the Sound, instead.

In 1891 the U.S. Army Corps of Engineers gave its backing to the project. Some preliminary work began in 1906, and work began in earnest five years later. In 1916 the water level of Lake Washington dropped by nearly nine feet when the Montlake Cut was completed, replacing the Black River as the lake's outlet in favor of Portage Bay and Lake Union. With the opening of the Locks on May 8, 1917, there was finally a navigable passage from the lake to the sound. from: Knowledgerrush.com

Map from World Maps Online

The first Seattle map seen by the outside world was produced in 1854 by a U.S. naval crew that dropped anchor in "Duwamish Bay" to chart its shoreline, part of the government's effort to survey thousands of miles of mostly-uncharted Pacific Northwest coastline. That chart shows a kidney-shaped inlet, half of it mudflats shielded by the roughly rectangular Alki peninsula. Midway down the eastern shore of the bay, at the edge of the mudflats, is a minor point of land with a spattering of about 10 dots representing buildings. The dots are labeled "Seattle," the name pioneers gave to the place where they built rustic homes on the site of an old Indian village.

The Seattle Glover drew in 1878 was a village of about 3,000 people, still focused on the lumber mill and dock at the foot of Yesler Street. Just south of Jackson, the town turned to mudflats. The tiny business district consisted of about six blocks; houses clustered between Seventh Avenue and the waterfront and north to Pine Street.

THE TOWN BEGAN to boom in the early 1880s, spurred by the arrival of the Northern Pacific Railroad in Tacoma, providing transportation for Puget Sound resources. Streetcars opened new residential areas. Real-estate speculators filed plats, which required new maps. The city needed topographical maps to design water and sewer lines.

Along came birds-eye artist, Augustus Koch, who drew a very different city. By 1891, Seattle's population had exploded to 50,000. Pioneer Square was a bustling commercial crossroads of ships and trains that crossed the mudflats on a network of trestles. Streetcar neighborhoods were booming along Madison Street, the Rainier Valley, up the slopes of Queen Anne Hill and out to Fremont and Ballard - about a dozen streetcar lines in all.

By 1911, Seattle was bursting its seams, in more ways than one. The population had multiplied to 240,000. Business, including real estate, was thriving. But the city's famous hills and lakes and waterways became obstacles. Seattle was fast becoming mired in its own geography.

Instead of building transit, the city had moved earth, leveling hills and using the dirt to fill the mudflats, digging a ship canal that linked Puget Sound to the lakes, straightening the Duwamish River and building a huge artificial island at its mouth to accommodate shipping. By 1915, Seattle had literally reconstructed its own landscape.

Instead of streetcar lines, roads would direct the city's dynamics. Up to 1940, the Eastside had been virtually irrelevant. Kirkland, linked to Seattle by ferry, shows up on maps from the 1930s, but Bellevue was still populated by berry farmers.

Then, in 1940, came the Lake Washington Floating Bridge. The rest is history.  from: The Seattle Times.

With the new Lake Washington Ship Canal in place, sloughs along the Sammamish River on the eastern shore dried up and marshes emerged from open water in Union Bay, near the Montlake cut. As the waters receded, houseboats and businesses on Lake Washington and LakeUnion found their sewer outfalls dumping onto exposed mudflats. At the southern end of Lake Washington, engineers had turned the Cedar River, which had flowed into the Blake river, into Lake Washington to provide sufficient water for the canal. When the locks were open, the black river began to disappear. More than one hundred acres of new land emerged. Read more at: University Libraries