Tim Johnson recalled the 30-year anniversary of a multiple landslide event in Whatcom County, Washington cascadiaweekly.com/recalling_the_30th_anniversary_of_the_smith_creek_landslide. The article includes some quotes from a certain geologist. The context of the anniversary has much to do with a policy issue that is and has been much discussed and considered that I have posted a few times and summarize in a longish manner HERE (lake-whatcom-reconveyance).
Tim points out how the storm and related landslides associated with forest practices brought about a policy shift regarding Lake Whatcom management, forest ownership in the watershed, forest practices in the watershed and in more recent years the move towards local control over 8,000 acres in the watershed.
But the 1983 event brought about other significant changes as well. The general view of forest industry practices took a stronger shift towards better regulation. The urgency of those changes increased somewhat due in a large part to practices that damage endangered salmon species habitat. The 1983 events were a clear demonstration of how forest roads posed a threat to neighboring properties sometimes miles from where the road was built such as at Smith Creek. Poorly constructed forest roads have also impacted shared natural resources and stream habitats. The 1983 storm event event at the Lake Whatcom watershed and elsewhere in northwest Washington not only caused damage during the event, but harmed streams and the lake itself for perhaps a decade or more as the excess sediment and debris introduced to the streams was processed and transported in subsequent years. Some of the policy issues regarding forest practices and forest road issues are still playing out as we learn more about the best approaches and how to consider risk in a reasonable way.
Thinking about how a single storm in 1983 can have lasting policy implications caused me to consider other storm events that have shifted policy.
November 1990
In early November, a large flood event on the Nooksack River caused a rethinking of flooding in Whatcom County. In addition to the 1990 flood, a large damaging flood had taken place just the year before after early fall snow followed by rain.
Tim points out how the storm and related landslides associated with forest practices brought about a policy shift regarding Lake Whatcom management, forest ownership in the watershed, forest practices in the watershed and in more recent years the move towards local control over 8,000 acres in the watershed.
But the 1983 event brought about other significant changes as well. The general view of forest industry practices took a stronger shift towards better regulation. The urgency of those changes increased somewhat due in a large part to practices that damage endangered salmon species habitat. The 1983 events were a clear demonstration of how forest roads posed a threat to neighboring properties sometimes miles from where the road was built such as at Smith Creek. Poorly constructed forest roads have also impacted shared natural resources and stream habitats. The 1983 storm event event at the Lake Whatcom watershed and elsewhere in northwest Washington not only caused damage during the event, but harmed streams and the lake itself for perhaps a decade or more as the excess sediment and debris introduced to the streams was processed and transported in subsequent years. Some of the policy issues regarding forest practices and forest road issues are still playing out as we learn more about the best approaches and how to consider risk in a reasonable way.
Thinking about how a single storm in 1983 can have lasting policy implications caused me to consider other storm events that have shifted policy.
November 1990
In early November, a large flood event on the Nooksack River caused a rethinking of flooding in Whatcom County. In addition to the 1990 flood, a large damaging flood had taken place just the year before after early fall snow followed by rain.
These two floods led to the county creating a County-wide flood tax district for generating funds for reducing flood risks. The City of Everson which had been hit hard by both floods pushed forward with an ambitious levy project that thus far has not allowed a flood into the main part of the city since. That approach along with the widening of the state highway bridge at Everson has reduced the flood risk frequency in Everson, but increased the downstream frequency. Several other major levy projects with lasting consequences moved forward at other locations on the river as well as on some tributary streams - not all were very well thought through and were at least in part the result of having lots of money without a comprehensive flood plan, a problem that has at least been partially resolved (warrants a few posts).
Winters of 1996-1997 and 1997-1998
The winter of 1996-1997 was very wet. But added to the generally very wet conditions was a huge snow storm over western Washington on New Years Eve. In some areas of western Washington there was already a lot of snow on the ground. It was the one year I thought it a good idea to go up and shovel snow off the roof (a drift from blowing snow off our neighbors roof had reached nearly 4 feet deep on our back roof). The cars on our street in Bellingham had become mounds without a single bit of steel visible on the entire street. And that was snow condition before the New Years Eve Blizzard arrived. Another foot of snow fell that night and early morning and the snow extended deep down to the south throughout the Salish Sea lowlands. The temperature crept up afterwards to a bit above freezing and then it began to rain. A lot of rain and a rapid increase in temperature.
Roofs collapsed - particularly car ports at apartment buildings and covered marinas. But for geologists the big story was steep shoreline bluffs failed at a remarkable rate. Not just steep slopes but steep slopes with homes. Or worse, steep slopes with homes below. Homes that had been permitted by various local governments. Slope stability became real. It was not some abstract thing that might happen. A writer for the Atlantic Magazine pointed out the disparity of funding for landslide research and development regulations compared to earthquakes even though landslides were equally bad at killing people. This was in part due to her living on Bainbridge Island where a family was buried and killed in their home.
The winter of 1997-1998 did not have the single dramatic landslide inducing storm of the previous winter, but it was very very wet and was likely additive to the wetness of the previous year. During that winter, there were not nearly as many landslides, but numerous, very large, deep-seated landslides reactivated including ones at sites with homes. A slide in Kelso and another near Olympia impacted dozens of homes.
The cumulative results of hundreds of landslides, property damage and deaths reached the policy action level. Subsequently fairly robust geologic hazard codes regarding landslides were implemented by local governments via local Critical Areas Ordinances as required by the State Growth Management Act. Most communities treated these hazards in an appropriately cautious manner. I will add, that Whatcom County also did a good job on recognizing alluvial fan hazards due to the 1983 event, whereas other communities have not recognized this risk nearly as well.
The other big change was that the State Legislature passed a law requiring geology licensing for the practice of geology. Geologic determinations can only be made by a geologist. There is still some lingering code issues on this matter in a very few communities that likely will take time to resolve, but most counties and cities have done a good job with landslide hazards.
Weather Events From Far Away
Climate events elsewhere may also have a big impact on policy in Washington State. To a degree Hurricane Katrina and I suspect Sandy as well as others that are easy to forget living so far away will, if they have not already, play a role in flood policy. New rules for levy construction and maintenance are being implemented with no small amount of controversy in Washington State. Federal Flood Insurance is hitting financial walls due to communities elsewhere (including some in Washington State) being very permissive about flood plain development. The ripple of far away events shape how the US Army Corp and FEMA approach flood issues.
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