Pilings, nothing more than Pilings

The foundation of the urban infrastructure

Spend any time wandering the shoreline of Puget Sound and you will see pilings. A handful providing a perch for an eagle. A dozen jutting just above the water, perhaps remnants of a stop for a mosquito fleet vessel. A long row originally built for a breakwater now mouldering and sort of scary looking. Hundreds supporting a modern pier, dock, ferry landing, or wharf. No one knows how many wood pilings were pounded into the sediment of Puget Sound but it must number in the hundreds of thousands, if not into the millions.

Pilings were essential for the business development of the Sound’s tidal waters. For example, in May 1876, work began at what is now First Avenue South and South King Street and was then the southern most point in Seattle, on the town’s first attempt to build a structure across the Duwamish River tideflats. To facilitate crossing the tideflats, workers brought in a barge-like boat equipped with a pile driver. This simple machine forced piles into the ground by dropping a heavy iron weight, or ram, onto the end of the wooden log. With mud more than 30 feet deep on the tideflats, the piling had to be up to 65 feet long.

Two whacks of the 3,000-pound-hammer would push the piles down through the soft mud to harder material below, with more blows—sometimes over 150—required to sink the log to a stable depth. Pile drivers used on Puget Sound in the 1890s struck 70 blows per minute. A report in the 1890s described pile drivers putting in from 26 to 200 piles per day. Within months, enough pilings had been pounded in to build the first trestle across the tideflats; it would soon carry Seattle’s first important railroad—the Seattle and Walla Walla, which only made it as far as Renton—and help transform the city. (The Seattle P-I also reported that the track atop the trestle was a popular location for couples to promenade, though they needed to watch out for trains.)

Pilings on the Duwamish River tideflats 1885. Star about equal to King Street and 1st Avenue. Red line is Seattle and Walla Walla trestle.

With the success of the S&WW, a mad battle began to transform the Duwamish River’s tideflats. Railroads and businesses and individuals drove pile after pile after pile, rapidly constructing the scaffolding upon which to build the city’s industrial base, which spread across the tideflats and on the shoreline around downtown. (A few years ago, one building that sits on pilings (619 Western) had to have a complete seismic retrofit because the pilings it sat on had decomposed. As the tide rose and fell, salt water infiltrated the sea wall and changed the ground water level, which resulted in periodic drying and inundation of the piling.)

One reason, of course, pile driving could occur was the region’s incredible forests with their seemingly unlimited supply of straight and strong trees. How many Douglas firs went from land to sea is incalculable but certainly must equal vast ecosystem devastation. As was the pounding in of pilings, which resulted in the decimation of the habitat of the shoreline and tideflats.

A decade after the completion of the S&WW, the tideflats was booming, primarily because of pilings.

At present, we tend to overlook the importance of pilings to the infrastructure of urban Puget Sound. And, yet, I would guess that if we could strip off the skin of the towns and cities built on the shoreline we would find that tens of thousands of those pilings still remain, buried under fill and concrete, a silent forest that testifies to the dreams, drive, and ambition of those who came before.

Seattle post Great Fire of 1889, revealing the acres of pilings that allowed the city to build out over the water. Probably many still exist, the bones under the urban skin.

---

I have a favor to ask. I am trying to spread the word about my newsletter so if you feel comfortable sharing it with others, I’d appreciate it. And, don’t be shy about encouraging them to become a subscriber, too; it’s free.