Reactive adaptation to avoid an unacceptable situation of escalating risk.

Sally Brown provides a nice overview of the various complexities of sea-level rise (What drives uncertainties in adapting to sea-level rise?). Its a worthwhile read just to get an introduction to what has to be accounted for in trying to project sea-level rise - much more than simply projecting melting ice and thermal expansion of water.

A fair bit of the article discusses uncertainty and how it may be dealt with in regards to sea-level rise. The whole issue of uncertainty has been manipulated mightily in the course of where climate science meets policy. Brown expresses frustration with how climate science loves to talk about uncertainty.

Late in the article Brown suggests a concept regarding sea-level rise: "reactive adaptation to avoid an unacceptable situation of escalating risk". The concept could just as well be applied to geologic hazards and risk and to some extent is being used already.

The quoted phrase could be modified for some geologic hazards and risks. In some cases, the hazard may not have been previously understood. For example, the potential for a large Cascadia earthquake was not known until the 1980s. Prior to the mid 1980s the potential for a large subduction quake was suspected based on what was know about plate tectonics, but there was a lack of evidence supporting big quakes. Since the 1980s, our understanding of the hazard and the risk posed has greatly improved.

The same could be said for the Seattle Fault. Also for the hazards posed by the various volcanoes.

Since there is now a better understanding of these hazards there is a better understanding of the risks. The risk posed by the Cascadia Fault has not changed, but our understanding of that risk has. The risk escalation is simply that we now understand the risk far better than we once did. Indeed there has been some "reactive adaptation" to avoid or reduce some of the unacceptable situations from what was previously an unidentified risk.

There will always be a some uncertainties regarding geologic risk. There is still much to be worked out regarding the Cascadia Fault and Seattle Fault as well as a number of other fault zones in Washington State. The same is true with our large strato volcanoes. But despite that uncertainty, reactive adaptation has moved forward.

I have touched on this theme previously (geologic-consent-and-civilization). How we react and adapt to geologic hazards as well as alteration of the atmosphere is measure of our civilization's capability of dealing with unacceptable risk.

 

HB 4776

Susan DelBene has introduced House Bill 4776 (house-bill/4776/text). Ms. DelBene's U.S. Congressional district includes the Oso area. The purpose of the introduced bill is begin the process of a national approach to landslides. The funding section is very modest given than national scale of the problem - $8 million for landslide hazard mapping and assessment (but also suggests prioritization which could mean a shift in existing funding) and $10.4 million for grants. The grant part would may assist the Washington State Geology Division's efforts to develop a state-wide landslide program.

All good, but the later question will be What will be done as landslide hazard areas are identified?At a national level, What, if anything, should the federal government do or require of states regarding landslide loss reduction. At the State level, What if anything should the State require of local governments?

Failure to take action with regard to identified landslides has life and fiscal consequences. Those consequences impact all of us. A statement in the bill that I was glad to see was "compile, maintain, and evaluate data on The nationwide impact of landslides on health and safety, the economy, and the environment".   

Notes on Recent Wenatchee Heights Landslide

Dave Petley noted the landslide south of Wenatchee chelan-county-landslide and some good photographs are provided by komonews.com photos.

The landslide is within an area mapped with multiple landslides. A massive slide complex that extends from the Columbia River all the way to the mountain crest thousands of feet above is located just to the east.

Part of the Wenatchee 1:100,000 Quadrangle (Tabor and others)

The recent slide is located a bit west of the W in Wenatchee Hill on the map

Note the slide movement arrows on the map including one just east of Qs on the map where the recent slide has moved.

Waitt describes the landslide complex within in the Wenatchee map pamphlet. The general idea is that massive blocks of earth have moved down the slope in an old landslide complex. More recent secondary slides are superimposed on this slide. The bright green (Tw) on the map is designated the Wenatchee Formation. There is some uncertainty in this area of the map regarding that designation in part due to the lithologies being disrupted and displaced by the large scale slides.

The Wenatchee Formation is an alluvial sedimentary formation that is approximately 35 million years old. Hence it predates the Columbia River Basalt Group. The formation is preserved so to speak within a large graben like drop down structural block. The formation contains clay units and is not particularly hard; hence, slides within the clay units may be the problem.

This landslide area is very different than many other landslide areas in Washington State. For one thing this area was not glaciated nor did the huge ice age floods reach this slide location. That means the Wenatchee Formation underlying the area has had time to become deeply weathered and clay formations may have become weathered and softened at considerable depth.

There is a topographic indication that the recent slide is within a larger old slide. The topography also suggests that the slide is very old as streams have incised into the old slide and the slide slopes do not appear sharp edges - that is they have been weathered. The best DEM I have available shows some lumpy ground indicative of a slide along with a shape of a slide, but also shows incised drainages and lack of sharp slide scarp edges.

Two old slide areas are in central area of image

The creek valley on the west side of the old slide has down cut and created a steep slope fronting the old slide and may have set up the right geometry. Some long term deep weathering may have added to the instability. And then this past winter has been very wet. Another factor may be the development of orchards on the old slide area contributing water. Roads redirecting water may also have been a factor. These factors may have taken awhile to weaken the clay below. The images and descriptions suggest that the slide area is smaller than the whole old slide feature and may be a relatively shallow secondary feature with little relation to the old slide.

Lots of "mays" in the paragraph above. The slide is complex and figuring it out and what to do will take some time. Chelan County has hired a geotech firm and issued warnings and closed the road. The slide was reported to still be moving.

Pangborn Bar Server Farm

A relatively new feature on the landscape of eastern Washington are server farms. Not a new type of agriculture, but very large computer facilities for data storage. (http://sabeydatacenters.com/intergate-columbia/).

 

This facility was built about eight years ago in East Wenatchee in Douglas County. The site is on the Pangborn Bar, a large gravel bar formed during the early ice age floods along the Columbia River. A large complex of ancient landslides with the Columbia River Basalt Group rises up on the slope above the massive gravel bar.

The site is near perfect server farm site with cheap stable hydro electric power from nearby sources (Douglas County Public Utility District) and inexpensive land area. The $100 million facility is a big boost to the local property tax.

Not far from this site a cache of spear points was uncovered (Moises Aguirre and Mark Mickles discover prehistoric Clovis point artifacts in an East Wenatchee apple orchard on May 27, 1987).
The juxtaposition of two leading edge technologies 10,000 plus years apart on the Pangborn Bar.

Luke Kelly

A little tribal pride today so a bit of Luke Kelly for the day. The first is Black Velvet Band with the Dubliners - a nice raucous ballad. The second is The Town I Loved So Well. A song written by Phil Coulter about Derry and The Troubles.

Climate Models and Foreign Policy

The Syrian crisis receives a great deal of international news coverage in the U.S. For good reason. Pundits and presidential candidates (some not very presidential) pitch solutions or criticisms.

While much is made of social forces in the conflict, there have been natural forces at play as well. Climate change has been a significant contributor to the disruption of the already fragile social order (a-note-on-syria-exponential-case-study).


Cook and others (2016) evaluated the current drought and conclude its the worst drought in the region over the past 900 years. Kelley and others (2015) correlate the severity of the drought with anthropogenic forcing.

A good case for taking account of climate models for foreign policy.


 

Too Short of Note on the Big Tidal Surge of March 10

A bit thin on posts of late - work and travel.

The storm event tide surge appears to have been a rather major event. Reports trickling in from folks describing some major shore alterations. An opportunity for some before and after images. I have one report from a beach that I have visited several times that had an area of elevated well established vegetation with drift wood logs. All but one log is gone. A reminder to always consider the worst case scenarios in assessing hazards.

I am looking forward to taking a return visit to a few familiar shore reaches. Should be interesting to see what my coastal expert associates observe as well. 

Storm Surge Driftwood Rim at Penn Cove

I wrapped up my field days with a low bank site on Whidbey Island. The folks there indicated that the storm had generated the highest water they had seen in over 10 years. I noted several places the past two days where water had been high including drift wood up over the bulkhead at the end of Adams Street in Port Townsend and evidence of water and driftwood along a few low bank roads. The high water left a driftwood rim well up and inland from the beach at the head of Penn Cove.

Futurewise Lay of the Land

Futurewise has put out a report on stormwater and low impact development (Lay of the Land LID). Thus far I have just glanced through, but it appears to be raising some interesting questions and my quick glance indites that geology, that is the lay of the land, gets some much needed attention or consideration when it comes to stormwater.

A good weekend read except I am working. This wet winter has caused some troubles.  

Notes on the Dynamic North Shore of Bellingham Bay

A little shore bluff history review of the north shore of Bellingham Bay indicates that this a very dynamic area. Click on the images to make them larger.

GLO 1860 last update 1915

The above early map Government Land Office map does not reveal a lot about the shore, but does note a road inland from the coast and notes the former location of Fort Bellingham.

1887 T Sheet

The T-Sheet map of 1887 denotes that the upland area where the fort had been located is farm fields. The stipple pattern on the shore suggests a broad beach.

1941 (USGS)

The 1941 aerial shows a narrow beach with broad tide flats can be seen. The Nooksack River is flowing onto the tide lands on the northwest part of the image.

1972 (USGS)

This 1972 image shows substantial apparent changes along portions of the shore. Note that the river channels have eroded into the shore along the northwest part of the coast removing the beach. However, the beach just to the right of that eroding area appears wider.

1977 oblique aerial (Ecology)

A close look at the oblique aerial from 1977 shows that the beach is covered with drift wood logs.

1998 (USGS)

More change is evident by 1998. Note trees are growing out of the driftwood deposits, but that with a river channel hard up against the base of the shore bluff the west half of the beach has been eroded away.

2005 (Google earth)

The trend of erosion continued into 2005 making its way across 2/3 of the south facing shore, but note that the river channel is starting to split as the delta sediments pile up.

2006 Oblique (Ecology) showing closer view if eroding shore section.

2014 (Google earth)

By 2014 the main river outlet channel had shifted out of the image area well to the west. Note the bright green area where the shore has built up.

2015 (Google earth) 

The bright green swath was apparently short lived as it is missing in the 2015 image.

Much of the "sediment" along this shore reach consists of wood. Driftwood is a big part of the material, but there is also a fair bit of small bits of wood, The source of the small wood pieces has been a bit of a mystery.

This shore reach has been dynamic and raises a number of questions in terms of what are the influences.

One is Where is all that wood coming from? Will large logs continue to be a major part of the shoreline processes at this location? Does the log deposit represent a temporary perhaps decade or century long factor? Will the site return to the condition observed in the 1941 aerial with a narrow beach?

The historic images show that the Nooksack River delta plays a significant role in shoreline processes along this shore reach. This is a very dynamic shoreline in part because of the presence of the river delta. The delta is a very rapidly growing delta due to the large sediment loads delivered by the river. As could be seen in the historic aerials, the presence of a large delta river channel within the tidal area along the shore likely contributed to erosion of the shore. That erosion has ended in the past 5 years and log accumulation appears to have begun again. This change appears to be the result of the main river channel having shifted to the other side of the delta far from this shore reach.

Overall the Nooksack River delta has been expanding rapidly into the bay. There is some evidence elsewhere on the Nooksack River that the river has not been flowing into Bellingham Bay for very long. Pittman, Maudlin and Collins (2003) propose that the Nooksack River may have shifted to its current flow towards Bellingham Bay within the very late Holocene. The shift was recent enough that there is a significant Lummi Nation oral tradition of the river change and is supported by archaeologic evidence.

The significance of the Nooksack delta and its likely newness may in part explain the accretion on the shoreline taking place during historic times and suggests that shoreline processes evaluation has some complicating factors in that the processes are relatively new compared to other Salish sea shore lines.

The sediment along the beach waterward of the is derived in part from the sediment deposited by the river. However, the site is also down drift from bluffs to the southeast (Coastal Geologic Services, 2009). Erosion of the bluffs to the southeast provide sediment to the beach and that sediment is transported by wave action northwestward towards the shore fronting the bluff at the north end of the bay. Historically the source of sediment to the beach from bluff erosion to the southeast has been reduced due to shore structures in the area where the bay waterfront has been developed. Rock armoring has been placed below areas where the railroad tracks are located and thus the sediment supply has been somewhat reduced.  

Daffodils on the Skagit Flat

Had some weekend excavation work to tend to.  

But after excavation work was done I caught the daffodil blooms on the Skagit Flats west of Mount Vernon.

A few tourists or locals had stopped. Turns out two of my neighbors were visiting this field as well. The hills in the distance are Mt Erie on Fidalgo Island and high points of various San Juan Islands including Mount Constitution.

Another field with the Northwest Cascades in the distance.

The daffodils are a bit early this year as it has been a very mild winter. Apparently saturated fields from heavy rain has not slowed the bloom time down.

The Daffodils do not bring out the tourists as much as the later blooming tulips will. A sunny weekend day on this same road would require some patience during the tulip bloom. 

Proposed Wolf Bauer Point

The Whatcom County Council passed a resolution supporting the naming of a point of land along Birch Bay Wolf Bauer Point: http://www.co.whatcom.wa.us/DocumentCenter/View/15900.

Birch Bay and proposed Wolf Bauer Point

My introduction to Wolf Bauer was his work on assessing the shoreline processes at Birch Bay. He very early on recognized that the alterations along the shoreline that had taken place in the past would have long lasting consequences that would harm other private property, public infrastructure, recreational uses and environmental resources. His visionary approach to Birch Bay will ultimately have to be done and is close to coming to fruition. Hence, it is fitting that his name be applied to a shoreline land-form at Birch Bay.

The particular land-form is rather remarkable.

Sediment from landslides and shore erosion on the bluffs on the outer south edge of the bay is transported towards the head of the bay by wave action. The point is at the end of an amazingly long berm that separates Birch Bay and the lower end of Terrell Creek for a distance on nearly two miles.

Wolf Bauer left a legacy of rethinking the Washington State landscape. He was a pioneer of mountaineering in the Cascade Range inspiring others to climb in the Cascade range as well as elsewhere in the world. He helped popularize kayaking as a means of local recreational transportation and interaction with the Pacific Northwest environment. He was instrumental in the formation of the Washington Environmental Council, an environmental policy advocacy group that has shaped how Washington views and manages the environmental resources we have. He played a key role in the development and passage of the Shoreline Management Act.

Wolf Bauer died late last month at the age of 103 (seattletimes.com/obituaries/wolf-bauer-103). He left Washington State a better place.