Sunday, February 26, 2012

The Denny Regrade

["spite mounds" created by the Denny Regrade project in Seattle, 1904-1931; note the jet hose in the center of the picture blasting away at the mound on the right and all of the ladders and sluice tunnels at the bottom of the photo, with a person holding it for scale; the Denny Regrade is just one of the many "geological slurry" events in the seismically active, glacially scoured landscape of the American Pacific Northwest]

The latest installment of the “Advancing Deltas” research is up over on Free Association Design.  There Brett Milligan gives a fascinatingly detailed chronicle of the large-scale movement of sediment from the former reservoir behind the now-breached Condit Dam on the White Salmon River to the much larger Bonneville Dam on the Colombia River.  The tale is an actor-network-history of the breach, one in which the scientists and engineers have the ability to mobilize huge quantities of sediments yet are thwarted in their attempts to even monitor certain aspects of the “compiled torpor… suddenly jettisoned across landscapes like a geological slurry.”

Towards the end of the account Milligan questions whether previous engineering notions of systems thinking and their concomitant reductionist tendency and focus on control would allow for the conceptualization of interventions such as the Condit Dam project.  He rightly points out that with the current project a measure of control is still present, though in “new and expanded forms.  Here we are subject to the forces of water and the enigmatic behavior of huge repressed swarms of particles.”

Lured by this event and Milligan’s a-n-t account we couldn’t help digging into a few other instances of these historical “geological slurry” events in the Pacific Northwest for a bit of context and comparison.  In 1894 the largest meteorological flood in the history of the Columbia occurred.  At the town of The Dalles peak discharge was measured at 35,100 cubic meters per second, enough to cover a football field in 25 feet of water every second.  By contrast, the highest peak discharge recorded on Europe’s largest river, the Danube, was 15,900 cubic meters per second, the peak discharge on the Mississippi during the Flood of 1926 was over 70,000 cubic meters per second.  The flood wiped out the old fort and an adjacent small town just north of where the Bonneville Dam is now located.  These were both 19th century constructions that had sprung up to control the portage around the cascades on the Colombia River.  Those cascades were the material remnant of another, much larger event.

Perusing the USGS circular on the largest floods in history shows this 1894 flood to be only one tenth the size of the flood of 1450 caused by the breaching of the “Bridge of the God’s” earthen dam.  The dam was created earlier when the southern faces of Greenleaf Peak and Table Mountain were sent hurtling into the Columbia River Gorge by the Bonneville landslide.  The event created a stillwater reservoir behind the dam for some 100 miles that reorganized the settlement patterns of the Klickitat and Chinook living in the area and drowned forests for 35 miles east of the dam.  When the dam broke due to the water pressure and seismic activity, the result must have been something like that flood on Alkali Lake that almost drowned the X-men and turned Gene Grey into the Phoenix.  The remnant was the Cascades.
[a google earth image of the Bonneville landslide area on the Columbia River; the fort and town of Little Cascade that was wiped out in the flood of 1894 was built along the portage road which cut through the area labeled "Bonneville Landslide"; the landslide was caused by sloughing off of the southern half of Greenleaf Peak and Table Mountain and resulted in a huge earthen dam on the Columbia; today the course of the river is more than 1 mile to the south and the cascade near the Bonneville Dam, in addition to the massive escarpments on what remains of the mountains]

The Denny Regrade
Lest we think, however, that the geologic history of the Pacific Northwest is merely some romantic transcendentalist tale of the power of nature and the pitifulness of humans, the boomtown of circa-1900 Seattle offers us the Denny Regrade project.  Undertaken as part of a sweeping public works agenda to boost real estate values and reconfigure the town into a major population center, the Denny Regrade was nothing less than the sluicing of an entire hill into Elliot Bay.

Blasting away at 16 million cubic yards of earth with 20,000,000 gallons of water per day and running it downhill into the bay was of course met with a certain resistance.  For one, the crumbled geology itself proved difficult.  The hills of Seattle were depositional sediments formed when glaciers receded and the variegation and size of some of the sediments required the mobilization of a wealth of instruments- sluices, tunnels, conveyor belts, horse drawn tractors and wagons, power shovels, short-track railroads, and scows with specially designed seacocks were all put to use as the project progressed over the next three decades.  In addition, the property rights of certain residents who refused to budge meant that their houses were left standing like the sweet old man in “Up” while the grading went on around them.  These contested actions left the intrepid residents stranded 100 feet in the air until these “spite mounds”, as they were known, eventually succumbed and Virgil Bogue was brought in to provide his vision for the future city.  It was an insane and wildly ambitious project, and even though the geological material was corralled, the Bogue Plan was soundly defeated and the visions for a new downtown and real estate bonanza never came to fruition.

The picture rendered through actor-network-theory is less one of a great battle with humans on one side and nature on the other, the two clashing heroically together atop their trusty steeds on Battlefield Earth, and more a kindergarten playground with shifting allegiances, unfair bullying, promiscuous flirtation and pants-wetting, all in a short half-hour.  The “Advancing Deltas” research is an exciting new chapter in this story.  When seen in this broader context one of the issues that the research project surfaces is that of the agency of things, be they Pliocene-era geologic formations, Chinook settlement patterns, white salmon, homeowners in Seattle, or the best-laid plans of internationally renowned designers.  More specifically, it calls our attention to issues of agency and intentionality, and the liminal space created by the difference between the two.
[the fate of the Denny Hill; an actor network history might trace those individual sediment particles down to Elliot Bay to check in on how they gave rise to new docklands or strip malls]