Boeing Plant 2 became obsolete by 2010 after building B-17s and early 737s; demolition reused nearly 100,000 tons of crushed concrete as backfill on the Seattle site

It is only fitting that a structure which stood for 75 years as a place that produced flying machines now finds itself being reduced to rubble and buried right back where it once stood. Such was the fate of Boeing Plant 2, the Seattle facility where over 7,000 B-17 Flying Fortresses and even the very first Boeing 737s rolled off the assembly line. As per the official Duwamish River environmental backgrounder issued by Boeing itself, an estimated 85 percent of the materials in the plant, ranging from steel, wooden beams, copper wire, and concrete, were recovered and reused.

This is an intriguing account of industrial recycling on a scale most people may never even consider, thinking: demolition only equals a wrecking ball and a dumpster. It's also, on closer inspection, a story of a company cleaning up after itself on a river it helped pollute over the preceding decades.

From Rosie the Riveter to a heap of ruins


Boeing Plant 2 was built in 1936 at the south end of downtown Seattle, next to the Duwamish Waterway. It grew to almost 1.7 million square feet during the war, and was even roofed in with fake suburban houses and trees, built by the U.S. Army Corps of Engineers to fool potential Japanese air raids; the plant itself was never attacked. Women replacing the men who were sent overseas to the factories had to fill the shoes of real-life "Rosie the Riveters" and, according to reports, the factory produced an average of 12 B-17s per day at its peak.

The building also housed the first three Boeing 737s built in the 1960s, though by then Plant 2 had already shifted away from primary aircraft manufacturing: it spent the 1970s and '80s largely as a production and machine shop for other Boeing work, then became a restoration facility for historic aircraft through the 1990s and 2000s, according to a University of Washington Pacific Coast Architecture Database publication that documents the site's production run from the B-17 through the 737. All remaining aircraft were finally moved out of the building in September 2010, and Boeing began demolition shortly after as part of a larger cleanup of the waterway beside the plant.

Well, where does 100,000 tons of concrete go?

A genuine surprise is Boeing's use of nearly 100,000 tons of concrete from the demolished plant as backfill right there on-site, per the same University of Washington archive, which draws on Boeing's own reporting. Separately, more than 10,000 tons of steel and a substantial amount of old-growth timber were pulled out and recycled elsewhere, into furniture and other building materials, rather than going into the on-site concrete backfill. Taken together, the demolition project looks less like destruction and more like a massive recycling operation.

It's a truly ingenious piece of engineering. Reusing the concrete on-site cut down on landfill waste, reduced the need for freshly quarried aggregate, and saved the fuel and emissions that would have gone into trucking tens of thousands of tons of rubble across the city. This is a story about waste and carbon footprint that should be getting a lot more attention for a generation that has come of age with hyper-awareness of construction waste and carbon footprints.

The part Boeing may not have put on a plaque

The U.S. Environmental Protection Agency designated the Duwamish Waterway, adjacent to Plant 2, as a federal Superfund site in 2001 as a result of decades of manufacturing activities that contaminated the sediments with PCBs, solvents, and heavy metals. Since then, Boeing has dredged away hundreds of thousands of cubic yards of contaminated mud and helped restore shoreline habitat for salmon; a quarter-century on from that designation, the EPA says that cleanup of the upland soil and groundwater is continuing at the site.

Yes, recycling 100,000 tons of concrete is a good thing, and more people should be doing it, instead of sending it to the landfill. It's worth noting, though, that the neat, feel-good version of the story, "aerospace giant recycles historic factory," goes a lot farther than the grungier version, "an aerospace giant still cleaning up a river that it helped pollute decades ago.” The two are correct. It may typically just be one of them that makes the news.