HomeMy WebLinkAboutA45 V6 Approved 2016 - Sect II - Natural Haz Q-ZJefferson County – City of Port Townsend All Hazard Mitigation Plan (Rev. 2016)
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TORNADO1
SUMMARY The Hazard: Tornadoes are the most violent weather phenomena known. They are characterized by funnel clouds of varying sizes that generate winds as fast as 500 miles per hour. They can affect an area of ¼ to ¾ of a mile and seldom more than 16 miles long. 2
Impacts and Effects:
• Death
• Severe Injury
• Destruction
Previous Occurrences: Table TN-1, below,
shows that there have only been 7 tornadoes
recorded in Jefferson County since 1950.
During all that time, there has been only one
injury.
Source: https://en.wikipedia.org/wiki/Tornado
Table TN-1. Recorded Tornado Events in Jefferson County Washington since 1950
Date Location Force Death(s) Injuries Distance
12/12/1969 Brinnon F3 0 1 27
11/24/1970 Port Townsend F2 0 0 27
04/09/1991 Brinnon F0 0 0 13
06/11/2001 Brinnon F0 0 0 19
06/05/2004 Port Townsend F0 0 0 26
05/18/2005 Port Townsend F1 0 0 25
01/18/2015 Brinnon EF1 0 0 28
Probability of Future Events: Extremely Low – Severe windstorms are far more likely than
tornados.3 Natural Hazard Risk Rating: The average natural hazard risk rating for tornadoes for all districts in
Jefferson County was estimated at 3.1, which is the lowest risk rating for all natural hazards that Jefferson County has seen.
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Definition
Tornadoes are the most violent weather phenomena known. They are characterized by funnel clouds of varying sizes that generate winds as fast as 500 miles per hour. They can affect an area of ¼ to ¾ of a mile and seldom more than 16 miles long. Tornadoes normally descend from the large cumulonimbus clouds that characterize severe thunderstorms. They form when a strong crosswind (sheer) intersects with strong warm updrafts in these clouds causing a slowly spinning vortex to form within a cloud. Eventually, this vortex may develop intensity and then descend to form a funnel cloud.
When this funnel cloud touches the ground or gets close enough to the ground to affect the surface it becomes a tornado. Tornadoes can come from lines of cumulonimbus clouds or from a single storm cloud.
Up until 2007, tornadoes were measured using the Fujita-Pearson Scale ranging from F0 to F5 (Figure TN-1).4 Table TN-2 shows the Fujita-Pearson Scale and it criteria. Since 2007, the “Enhanced” Fujita
Scale (EF) has been used to estimate the scale of a tornado based on 28 criteria. Table TN-2 shows the equivalence of the Fajita and the Enhanced Fajita scale. Table TN-3 presents the 28 criteria with which to evaluate a tornado’s destructive force.
Figure TN-1 - THE FUJITA-PEARSON SCALE4
The National Weather Service scales tornadoes by intensity on a scale of zero to five on the Fujita-Pearson scale which include: F-0. Light damage. Wind up to 72 mph. Some damage to chimneys; breaks branches off trees; pushes over shallow-rooted trees; damages sign boards. F-1. Moderate damage. Wind 73 to 112 mph. The lower limit is the beginning of hurricane wind speed; peels surface off roofs; mobile homes pushed off foundations or overturned; moving autos pushed off the roads; attached garages may be destroyed. F-2. Considerable damage. Wind 113 to 157 mph. Roof torn off frame houses; mobile homes demolished; boxcars overturned; large trees snapped or uprooted; light-object missiles generated; cars lifted off ground. F-3. Severe damage. Wind 158 to 206 mph. Roof and some walls torn off well-constructed houses; trains overturned; most trees in forest uprooted. F-4. Devastating damage. Wind 207 to 260 mph. Well-constructed houses leveled; structures with weak foundations blown off some distance; cars thrown and large missiles generated. F-5. Incredible damage. Wind above 261 mph. Strong frame houses lifted off foundations and carried considerable distances to disintegrate; automobile sized missiles fly through the air in excess of 100 meters; trees debarked; steel-reinforced concrete structures badly damaged. F-6 to F12. Toast City. Exponentially increasing force that was originally proposed as from 319 mph to Mach 1, the speed of sound. The maximum wind speeds of tornadoes are not expected to reach F6, therefore the public is generally unaware of this part of the scale. We would expect “Sharknado” before having an F6 or greater storm. The “Enhanced” Fujita Scale simply makes the top end of the F-5 scale open-ended.
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History of Tornadoes in Jefferson County
Jefferson County does not have a record of significant tornado activity. Generally, the Northwest lacks the big thunderstorms that spawn tornadoes. From the period 1880 through 2012, there have been no “officially” recorded tornadoes in Jefferson County.5 Yet, we have documentation of tornadoes occurring from 1969 thru 2015, albeit infrequently. We have no explanation for the divergence in agreement of sources.
Washington state usually experiences one to two tornadoes each year. In 2004, however, there were nine, while in 2007 none were reported. Wind patterns in Jefferson County are broken up by the Olympics, thus mitigating tornado spawning conditions.6
Table TN-2. The Fujita Scale vs the Enhanced Fujita Scale.
FUJITA SCALE DERIVED EF
SCALE
OPERATIONAL EF SCALE
F
Number
Fastest
1/4-
mile (mph)
3
Second
Gust (mph)
EF
Number
3
Second
Gust (mph)
EF Number
3
Second Gust (mph)
0 40-72 45-78 0 65-85 0 65-85
1 73-112 79-117 1 86-109 1 86-110
2 113-157 118-161 2 110-137 2 111-135
3 158-207 162-209 3 138-167 3 136-165
4 208-260 210-261 4 168-199 4 166-200
5 261-318 262-317 5 200-234 5 Over 200
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Table TN-3 - Enhanced Fujita Scale Damage Indicator
NUMBER DAMAGE INDICATOR ABBREVIATION
1 Small barns, farm outbuildings SBO
2 One- or two-family residences FR12
3 Single-wide mobile home (MHSW) MHSW
4 Double-wide mobile home MHDW
5 Apt, condo, townhouse (3 stories or less) ACT
6 Motel M
7 Masonry apt. or motel MAM
8 Small retail bldg. (fast food) SRB
9 Small professional (doctor office, branch bank) SPB
10 Strip mall SM
11 Large shopping mall LSM
12 Large, isolated ("big box") retail bldg. LIRB
13 Automobile showroom ASR
14 Automotive service building ASB
15 School - 1-story elementary (interior or exterior halls) ES
16 School - jr. or sr. high school JHSH
17 Low-rise (1-4 story) bldg. LRB
18 Mid-rise (5-20 story) bldg. MRB
19 High-rise (over 20 stories) HRB
20 Institutional bldg. (hospital, govt. or university) IB
21 Metal building system MBS
22 Service station canopy SSC
23 Warehouse (tilt-up walls or heavy timber) WHB
24 Transmission line tower TLT
25 Free-standing tower FST
26 Free standing pole (light, flag, luminary) FSP
27 Tree - hardwood TH
28 Tree - softwood TS
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Hazard Assessment and Vulnerability Assessment
Tornadoes are not normal occurrence in the Northwest the way they are in the Midwest. Tornadoes require a confluence of warm surface temperatures and warm fronts coming from the south with cold fronts coming
from the north. Northwest climates do not normally generate the temperature variations conducive to tornado formation. Washington is ranked 43 in the US for total number of tornadoes. Nonetheless, the tornado threat should be taken very seriously. The conditions conducive to tornado formation can develop in Northwest Washington, although it is not common for funnel clouds to be reported in this region. During
severe thunderstorms, it is possible for tornadoes to occur.7
Tornadoes in Washington tend to be light or moderate, with winds ranging from 40 to 112 mph. There are a notable minority of tornadoes that cause significant to severe damage with winds going as high as 200 mph. The peak season for tornadoes is April through July. However, in Washington tornadoes
may occur in the late summer months and, in a few rare cases, may occur in the winter months. While tornadoes are sometimes formed in association with large Pacific storms, most of them are caused by intense local thunderstorms. Tornadoes almost exclusively occur in the late afternoon and early evening. Normally, Pacific Northwest tornadoes are moderate but it is possible for serious tornadoes to develop, causing death and serious injury. Typically, tornadoes may cause severe damage to everything in their path. Walls collapse, roofs are ripped off, trees and power lines are destroyed. The challenge is that tornadoes, especially in the Northwest, are very difficult to predict and their onset is sudden. Unlike the tornado-prone areas in the
plains states, there is little awareness of the tornado threat and the forecasting and warning systems are less well developed. It is extremely rare for a tornado watch or warning to be issued anywhere in the Northwest. As such, there is little public awareness of the warning systems and self-protection
measures common to the tornado prone states. Climate Change
At this point in time, there is too much variability in wind speeds and storm events and too short of wind time series to be able to make projections of climate changes effect on the intensity or patterns of winds in the region.8
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Figures TN-2 and TN-3 contain provisional data released on November 14, 2016 by the NOAA National Weather Service Storm Prediction Center9,10. They show that the recent trend nationally is for fewer tornados.
Figure TN-2 – United States Annual Trends of LSR Tornados9
Figure TN-3 – U.S. Inflation Adjusted Annual Tornado Trend and Percentile Rank10
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Since we now have a 24-7 news cycle and since threatening weather is good for ratings, news media pump up the coverage of storms and tornados, often giving the impression that events are going to be
worse than they turn out to be. Just prior to October 15, 2016, the media hyped a “mega-storm” that was to have 150 mph winds to hit the Seattle area on October 15, 201611. There is anecdotal evidence that some local stations kept
on promoting how bad the storm was going to be – even after they had word from the NWS that the threat was mitigating.
Mega-storm packing 150 mph winds and
50-foot waves set to pummel West Coast
Source: medium.com
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Conclusion
Emergency response agencies should not be taken by surprise by a tornado in Jefferson County. While violent tornadoes are not a characteristic of the Northwest Washington climate, the weather systems that may generate tornadoes appear regularly. Emergency response agencies and emergency management officials should be prepared for the rapid notification of the public and for the efficient management of a mass casualty incident, and the prioritization of debris clearance. Figure TN-4 - Results of an EF-6 – EF-12 Tornado12,13,14
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References - TORNADO
1. “Tornado”, Jefferson County Comprehensive Emergency Management Plan, HIVA – Part 2
Section 2.4.11, Jefferson County Department of Emergency Management, 2008.
2. Clark County Washington Hazard Identification and Vulnerability Analysis, Clark Regional
Emergency Services Agency, 2003.
3. Severe Storm, Washington State Enhanced Hazard Mitigation Plan, Washington Department of
Emergency Management, Tab 5.7, 2014, p.6. http://mil.wa.gov/uploads/pdf/HAZ-MIT-
PLAN/Severe_Storm_Hazard%20profile.pdf
4. Fujita Tornado Damage Scale, Fujita, T. Theodore, University of Chicago, 1971. Source: Storm
Prediction Center, NOAA. Available at: http://www.spc.noaa.gov/faq/tornado/f-scale.html
5. “Washington Tornadoes 1880 – 2000”, The Tornado Project, St. Johnsbury, Vermont.
http:/www.tornadoproject.com/alltorns/watorn.htm (This table has been modified by the originator
so that it now goes from 1950 thru 2012.)
6. “Seven Washington Tornadoes: What’s Up with That?”, Wyatt, Susan, King5.com, June 7, 2004
7. Severe Storm, Washington State Enhanced Hazard Mitigation Plan, Washington Department of
Emergency Management, Tab 5.7, 2014. http://mil.wa.gov/uploads/pdf/HAZ-MIT-
PLAN/Severe_Storm_Hazard%20profile.pdf
8. Petersen, S., Bell, J., Miller, I., Jayne, C., Dean, K., Fougerat, M., 2015. Climate Change Preparedness Plan for the North Olympic Peninsula. A Project of the North Olympic Peninsula Resource Conservation & Development Council and the Washington Department
of Commerce, funded by the Environmental Protection Agency. p. 38. Available: www.noprcd.org 9. United States Annual Trends of LSR Tornados, NOAA-NWS, November 14, 2016. Available at:
http://www.spc.noaa.gov/wcm/torngraph-big.png
10. U.S. Inflation Adjusted Annual Tornado Trend and Percentile Rank, NOAA-NWS, November 14,
2016. Available at: http://www.spc.noaa.gov/wcm/adj.html
11. Mega-storm packing 150 mph winds and 50-foot waves set to pummel West Coast,
https://medium.com/@hul10/mega-storm-packing-150-mph-winds-and-50-foot-waves-set-to-
pummel-west-coast-78ee7a56ca6c#.9vdoeerzv
12. Sharknado Movie Poster, Accessed August 10, 2016. Available at:
https://en.wikipedia.org/wiki/Sharknado
13. Sharknado2 Movie Poster, Accessed August 10, 2016. Available at:
https://en.wikipedia.org/wiki/Sharknado_2:_The_Second_One
14. Sharknado3 Movie Poster, Accessed August 10, 2016. Available at:
https://en.wikipedia.org/wiki/Sharknado_3:_Oh_Hell_No!
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Tables - TORNADO
TN-1 Recorded Tornado Events in Jefferson County Since 1950, Compiled by Jefferson County Department of Emergency Management, August 2016. TN-2 Fujita vs Enhanced Fujita Scale, Storm Prediction Center, NOAA, Accessed August 2016. Available at: http://www.spc.noaa.gov/faq/tornado/ef-scale.html
TN-3 Enhanced Fujita Scale Damage Indicator, Storm Prediction Center, NOAA, Accessed August 2016. Available at: http://www.spc.noaa.gov/faq/tornado/ef-scale.html
Figures - TORNADO
TN-1 Fujita Tornado Damage Scale, Fujita, T. Theodore, University of Chicago, 1971. Source:
Storm Prediction Center, NOAA. Available at: http://www.spc.noaa.gov/faq/tornado/f-
scale.html
TN-2 United States Annual Trends of LSR Tornados
TN-3 U.S. Inflation Adjusted Annual Tornado Trend and Percentile Rank
TN-4 “Results of an EF-6 to EF-12 Tornado”, Sharknado Movie Posters to break up the monotony
of reviewing 600+ pages.
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TSUNAMI / SEICHE1
SUMMARY
The Hazard: Tsunamis are wave trains, or series of waves, generated in a body of water by an impulsive disturbance including earthquakes, subaqueous or terrestrial landslides impacting water bodies, or volcanoes. Impacts and Effects:
• Loss of life
• Loss of property
• Damage to critical transportation infrastructure
• Damage or loss of recreation facilities
• Disruption of utilities
• Loss of jobs due to damaged equipment and facilities Previous Occurrences: Geologic evidence shows that the Jefferson County area around Discovery Bay and the City of Port Townsend have experienced at least 7 major inundations in the last 3500 years2.
Probability of Future Events: High – Minor tsunamis have been documented every few years. There are several know faults and subduction zones capable of generating major tsunamis as part of
an underwater subsidence.
Natural Hazard Risk Rating: The average natural hazard risk rating for tsunamis for all districts in Jefferson County was estimated at 10.45, which would be considered low. Districts with water boundaries, however, consistently rate the risk at 40, which, while moderate, is among the highest ratings given for anything in Jefferson County.
Figure TS-1 Olympic Peninsula Tsunami Inundation Zones at 100’ and 600’3
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Definition:
Tsunamis are wave trains, or series of waves, generated in a body of water by an impulsive disturbance including earthquakes, subaqueous or terrestrial landslides impacting water bodies, or volcanoes. Tsunami waves, often incorrectly described as tidal waves, are extremely destructive to life and property. Imperceptible on the open ocean, they can travel at velocities of up to 1000 km/h. Tsunami waves are usually 100 or more miles from crest to crest and can reach heights of up to 30 meters. They can traverse the entire 12,000 to 14,000 miles of the Pacific Ocean in 20 to 25 hours, striking with
virtual undiminished force on coastal areas4. A seiche is the formation of standing waves in water body, due to wave formation and subsequent reflections from the ends. A seiche may be incited by earthquake motions, impulsive winds over the surface, or wave motions entering the basin5. A tsunami generated along the South Whidbey Island earthquake fault could send a wave directly into Port Townsend Bay, where it would wrap around the bay and create a seiche.
History of Tsunamis in Jefferson County
The Washington coast, including the coastal areas of Jefferson County, experienced a large tsunami following the 1964 Alaskan earthquake; however, no deaths were reported in this state. As recently as March 2011, a tsunami warning was issued for the Washington coast due to the Tohoku earthquake in
Japan, which created a tsunami that did reach our coast. Research indicates that an earthquake on the west coast of America at 21:00 on January 26, 1700 caused
a tsunami in Japan that killed thousands of people. Local evidence now indicates that the same tsunami damaged the west coast of Jefferson County and the lowlands of Grays Harbor and Pacific counties. This was caused by an estimated 9.0+ undersea earthquake along the Cascadia Subduction Zone, which
can happen again. The event, called a megathrust earthquake, created a large tsunami that crossed the Pacific Ocean and inundated Japanese villages without the shaking warning they were used to having. The Japanese documented the event, thus allowing us to get the exact time of arrival of the wave in Japan and to back calculate when the earthquake occurred on Washington coast6. At the time of the “1700 Tsunami”, there were only native and early explorer civilizations in the areas inundated in Washington. Today, there are billions of dollars of property and millions of people that could be directly affected. Seafloor core evidence indicates that there have been forty-one subduction zone earthquakes on the Cascadia subduction zone in the past 10,000 years, suggesting a general average earthquake recurrence
interval of only 243 years.7 Of these 41, nineteen have produced a "full margin rupture," wherein the entire fault opens up.8 There is also evidence of accompanying tsunamis with every earthquake. One strong line of evidence for these earthquakes is convergent timings for fossil damage from tsunamis in
the Pacific Northwest and historical Japanese records of tsunamis.9 Table TS-1 provides the approximate dates of the tsunami events occurring from Cascadia ruptures in the last 3500 years10. The interval ranges were from about 200 to 900 years with an average of about 500 years.
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The Washington State Emergency Operations Center was activated on June 9, 1996 after the Alaska Tsunami Warning Center issued a Tsunami Watch for the Washington coast and Puget Sound. An earthquake of 7.5 near Adak, Alaska generated a seismic wave of 2.5 feet. The state EOC returned to
normal operations on the same date after the Tsunami Warning Center determined there was no threat to Washington State. Although not a common occurrence, the history indicates that the potential for tsunamis exists for coastal areas and areas along the Strait of Juan de Fuca.
The Jefferson County Emergency Operations Center (EOC) has been activated multiple times to monitor for distant tsunamis from under sea earthquakes near Japan and along the South American coast. The Japanese earthquake at Honshu on March 11, 2011, created a massive tsunami in Japan, but also generated a distant tsunami that hit the Washington coast, including Port Townsend and Fort Worden State Park beaches. As the EOC tracked the tsunami across the Pacific, the City Manager gave orders to evacuate the vulnerable population of the Admiralty Apartments, a low-income residence on the Port Townsend waterfront. The tsunami wave did hit the Washington coast and Port Townsend, but, fortunately, was less than a meter high at its highest spot.
Hazard Identification and Vulnerability Assessment
The Pacific coastal areas and inland waters on the Strait of Juan de Fuca are the most vulnerable to tsunamis generated at a distance or by a local subduction zone earthquake. Distant tsunamis are those that originate so far away that residents of Jefferson County cannot feel the shaking of the earthquake that creates the wave. In most cases, nearby tsunamis will give warning by the shaking of the earthquake creating the wave; in some cases, though, the wave can be generated by a landslide and may not be heard or felt. Damaging tsunamis striking the Pacific Northwest coast over the past century were generated by distant earthquakes located far across the Pacific basin. These tsunamis are distinguished from earthquakes
near the coast, termed local tsunamis. Figure TS-2 shows how long it takes a tsunami to reach the Washington coast from across the ocean13.
Typically, the Port Townsend coastline and Port Townsend Bay have about 90 minutes before a wave hits once it enters the Strait of Juan de Fuca. A tsunami wave generated by the rupture of the Cascadia fault, off the coast of Washington, will take approximately two hours to reach the Port Townsend area
– depending on how and where the rupture occurred. A distant tsunami, such as was generated by the Honshu earthquake, can take seven or eight hours or more to reach Washington’s coast.
Table TS-1 Recurrence of the “Great Earthquakes” in Washington State
Estimated Year of Occurrence Return Interval
2005 Source11 2003 Source12 Years
1440 – 1340 BCE 1150 -1220 BCE Unknown 980 - 890 BCE 910 – 780 BCE 250 660 – 440 BCE 610 – 450 BCE 400 350 – 420 CE 250 – 320 CE 910 690 – 730 CE 550 – 750 CE 330
780 – 1190 CE 880 – 960 CE 210
9:00 pm, January 26 1700 (NS) 780
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Figure TS-2 Tsunami ETA Calculator
Source: Jefferson County Department of Emergency Management The Jefferson County Risk Report estimates that an earthquake in the Puget Sound along the Seattle fault could generate a tsunami that would reach Port Townsend in twenty (20) minutes.14
On the other hand, a rupture of the South Whidbey Island Fault or a landslide into the sea from Whidbey Island could cause a significant tsunami that would reach Port Townsend or the Fort Worden beaches in minutes. People on the beaches would still be picking themselves up off the ground when the wave hit. The South Whidbey Island fault is mid-way between Port Townsend and Whidbey Island, a distance of about one and a half miles. Figure TS-3 shows the location of the South Whidbey Island Fault15.
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Figure TS-3 South Whidbey Island Fault15
Source: Insurance Owl.com
It should be noted that all of Port Townsend, half of Marrowstone Island, and the Naval Magazine at Indian Island are all with Zone VIII, that of the most severe intensity. The land surrounding Discovery Bay and both ends of the Hood Canal Bridge are in Zone VII, “Very Strong” shaking. These have the
potential to send debris laden tsunamis down Discovery Bay to take out U.S. Hwy 101 and a power substation, and down the Hood Canal to take out the Hood Canal Bridge.
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The Washington Department of Natural Resources (DNR) has documented notable tsunamis that have occurred in Washington (Figure TS-4), and is working to model the coastlines for tsunami
hazard16.
Figure TS-4 - Notable Tsunamis in Washington16
Source: WA DNR Website
The Cascadia Subduction Zone Tsunami Generator17
The Cascadia subduction zone is an oceanic tectonic plate (the Juan de Fuca plate—the edge is indicated here by the Juan de Fuca Ridge) that is being pulled and driven (i.e. subducted) beneath a continental plate (the North American plate). Earthquakes along the fault that is the contact between the two plates, termed the interplate thrust or megathrust, may generate local tsunamis in the
Pacific Northwest. Except for the 1992 Cape Mendocino earthquake at the southernmost part of the subduction zone, there have been no major earthquakes on the megathrust in historic time. Some geologists offer that the Cascadia subduction zone is poised between major earthquakes. Therefore, the possibility exists that
local tsunamis may someday accompany a major earthquake along the Cascadia megathrust. Pacific coastal areas and inland waters on the Strait of Juan de Fuca are the most vulnerable to tsunamis
generated at a distance or by a local subduction zone earthquake. As a tsunami leaves the deep water of the open ocean and travels into the shallower water near the coast, it transforms. A tsunami travels at a speed that is related to the water depth - hence, as the water depth decreases, the tsunami slows. The tsunami's energy flux, which is dependent on both its wave speed and wave height, remains nearly constant. Consequently, as the tsunami's speed diminishes as it travels into shallower water, its height grows. Because of this shoaling effect, a tsunami, imperceptible at sea, may grow
Source: washington.edu
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to be several meters or more in height near the coast. When it finally reaches the coast, a tsunami may appear as a rapidly rising or falling tide or a series of breaking waves. A tsunami generated by a Cascadian Subduction Zone earthquake directly off the coast of Washington State, could arrive in less than a half hour. Tsunami waves from a Cascadia Subduction Zone earthquake located off the shore of Northern California or Northern British Columbia may reach the coast of Washington State in an hour or less.
Puget Sound is vulnerable to tsunamis generated by local crustal earthquakes or by submarine landslides triggered by earthquakes. Wave oscillations in enclosed or semi-enclosed bodies of water are called seiches. Seiches are caused by earthquake induced land surface waves that generate oscillations in bodies of water,
resulting in fluctuations of the water levels causing sloshing from one end to the other. In 1891, an earthquake centered near Port Angeles caused eight-foot waves in Lake Washington.
The death and damage that can be inflicted by a tsunami is notable. The wave action is destructive in itself, however floating debris left after the wave can continue batter coastline structures and development. Boats moored in harbors and marinas often are swamped and sunk, or are destroyed and stranded on the shore. Breakwaters and piers collapse. Storage tanks situated near the waterfront are vulnerable. Port facilities, fishing fleets, and public utilities are frequently the backbone of the economy of the affected areas, and these are the very resources that generally receive the most severe damage. Until debris can be cleared, wharves and piers rebuilt, utilities restored, and the fishing fleets reconstituted, communities may find themselves without fuel, food and employment. Wherever water transport is a vital means of supply and economic sustainment, disruption of coastal and inland seaports can have far reaching economic effects. Tsunami effects on fishing, mollusks, shore plants and marine and land organisms can be devastating. In addition to the enormous direct destruction caused by the waves themselves, salt water
can invade coastal lakes and destroy, at least temporarily the fresh water habitat. Jefferson County’s ocean coastal areas have many miles of cliffs and high banks that slow or retard wave
inundation. Lower elevation lands of river and stream outlets, however, do have small communities near their banks.
Port Townsend: The National Tsunami Hazard Mitigation Program’s Center for Tsunami Inundation Mapping Efforts has developed tsunami models to help jurisdictions along the Southern Washington Coast, and Port Angeles and Port Townsend prepare evacuation plans for a future tsunami. The models use a
moment magnitude 9.1 earthquake on the Cascadia Subduction Zone off the Washington coast as the generator of the tsunami. Figure TS-5, below, shows the inundation zone and evacuation routes for the Port Townsend area. City Hall and half of the grocery and hardware stores, and two power substations are within
the Port Townsend zone18. The police station used to be, but was moved out of the tsunami zone in 2009 with the aid of a FEMA Hazard Mitigation grant.
Projects covering these areas have identified at-risk communities (all census designated and incorporated places within one kilometer of the coast) and developed arrival times and wave elevations for them. For communities on the outer coast, the first wave crest is predicted to arrive between 30 and 60 minutes after the earthquake; in Willapa Bay and Grays Harbor, the first crest is not expected to arrive for more than an hour. Significant flooding can occur before the first wave crest because a Cascadia Subduction Zone earthquake is expected to lower the ground surface along the coast. Flooding of areas less than six feet above tide stage
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is expected immediately. Maximum flooding depth and extent will depend on tide height at the time of tsunami arrival.
Figure TS-5 Port Townsend Inundation Zones and Evacuation Routes18
Source: Washington State DNR
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For the Port Angeles and Port Townsend areas, the crest of the first wave is expected within 90 minutes of the earthquake, with significant flooding before the crest. West Jefferson County: Jefferson County’s west end consists of about 27 miles of open ocean frontage, small unincorporated towns, and two Indian tribes: the Quileute and the Hoh. Modeling of the Cascadia fault suggests that tsunami waves in excess of thirty feet high could inundate the shoreline. The Hoh Tribe
of Indians have the most vulnerable community with approximately 110 individuals, many of which are still in the inundation zone at the mouth of the Hoh River. They have been working diligently to acquire elevated land around the perimeter of the reservation in order to move their community center and emergency facilities to high ground to give tribe members a place to go during a tsunami emergency.
Figures TS-6 and TS-7 show the recognized tsunami inundation zone for the Hoh Tribe and the
Queets area on the Pacific coast19,20.
Figure TS-6 Hoh Inundation Zone and Evacuation Routes19
Source: Washington State DNR
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Figure TS-7 Queets Inundation Zone and Evacuation Routes20
Source: Washington State DNR THE COST OF A CASCADIA-GENERATED TSUNAMI The Risk Report for Jefferson County contains the assessment of the value of buildings that will be damaged or destroyed in a tsunami generated by a Cascadia M9 earthquake. Table TS-2 provides the estimate of buildings and their value in the tsunami zone.21 While a good way to compare against other areas, such as Port Angeles to understand relative vulnerability, it grossly understates the cost of the tsunami. The simulation scenario values buildings because it can, but it does not factor in that a
significant portion of the county’s economic engine is within the tsunami zone, along with 1/3 of Port Townsend’s grocery stores, three-quarters of its financial institutions, a power sub-station, and city hall. The time to recover and the cost of recovery will dwarf the value of the buildings damaged.
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Table TS-2 - Building Exposure to a Cascadia M9 Earthquake-generated Tsunami Along the Jefferson County Coast21
Source: Risk Report for Jefferson County
Figures TS-9 and TS-10 overlay buildings in the predicted tsunami inundation zone for Port Townsend
and vicinity and for the Hoh Tribal area with a “red tide” showing the projected limits of the tsunami.22,23 As of 2015, modeling suggested a maximum of about 7 meters or nearly 23 feet. The two bulges at top and bottom in the middle of the city map are China Lake and Kai Tai Lagoon, respectively. They are at sea level, but San Juan Avenue, which connects them in a straight line has a peak height of twenty-two feet, based on USGS topographic maps. If the tsunami wave height prediction is light, the wave could cut the city in two, taking out the Blue Heron Elementary School along the way. Why could it be light? The simulations are based on an M9 earthquake on the Cascadia fault; nothing says such a subduction zone earthquake couldn’t be of a stronger magnitude.
FIGURE TS-9 – PORT TOWNSEND BUILDING INUNDATION
IN A SIMULATED CASCADIA M9 EARTHQUAKE-GENERATED TSUNAMI22
Source: Risk Report for Jefferson County
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FIGURE TS-10 – HOH TRIBE BUILDING INUNDATION
IN A SIMULATED CASCADIA M9 EARTHQUAKE-GENERATED TSUNAMI23
Source: Risk Report for Jefferson County A LESSON LEARNED FROM THE TOHOKU TSUNAMI (2011) Jefferson County evacuation zones have been predicated on high ground being at 50 feet or higher. The latest inundation map (Figure TS-10, 2015) from WA DNR ends with wave heights at seven meters, about 23 feet.24 Figure TS-11 and the accompanying text from the Pacific Northwest Seismic Network show wave heights of the Tohoku Japan generated by an earthquake of magnitude similar to what we expect from a Cascadia Subduction Zone rupture. In some locations, wave heights reached 40.5 meters
or 133 feet, overtopping three story buildings designated as safe for vertical evacuation.25
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FIGURE TS-10 - PORT TOWNSEND INUNDATION ZONE – 201524
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“The Tohoku Japan M 9.1 earthquake on Friday, March 11th, 2011 provided horrifying images to the
world of great waves smashing through the best coastal defenses in the world and into the heart of coastal cities. The tsunami in Miyako swirled over the top of three story buildings designated as safe for vertical evacuation. Although the map shows “more than 8.5m”, the maximum wave height in Miyako
was reported as reaching 40.5 meters or 133 feet. The flooded Fukashima nuclear power plant lost its primary and secondary power systems that lead to the possibly the worst nuclear catastrophe since World War II. Japanese scientists made a serious mistake in thinking that a few hundred years of history defined the limit of how large earthquakes in the Japan Trench subduction zone could get. The consensus reached was less than M8.5; the "Great East Japan Earthquake" is estimated to have been a M 9.1. Evidence of a large tsunami in the year 869 C.E. had not yet been incorporated into the hazard assesments.25”
FIGURE TS-11 - TOHOKU TSUNAMI WAVE HEIGHTS25
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SPECIAL DISTRICT CONSIDERATIONS As with many major natural hazards, the occurrence of one often cascades into a series of calamities that exacerbates the circumstances and the ability of the area to recover. The Port of Port Townsend
has unique exposure above and beyond the issues that the rest of the County’s coastline has. Most of the Port’s assets are coastal in nature, ranging from marinas to one of two working Victorian seaports in the county, the other being on the East Coast. One assumes that the boats that are moored in the marinas and harbor are at risk for tsunamis. A significant wave can lift vessels and drop them in the roadways. In Port Townsend, this could result in the closing of SR20 until the debris was pushed to the side or removed. Debris in a tsunami wave can also severely damage the Ferry docks and the Hood Canal Bridge, thus nearly turning the Olympic Peninsula into an island.
For the Port, however, there are seasonal considerations, too. In August, there is a Wooden Boat
Festival that draws 20,000 visitors to the Port Townsend area (pop. 9,600), many in their own wooden boats. The Port Townsend Harbor is thick with boats and vulnerable to a significant tsunami. In the
Whidbey Island Fault scenario, there would only be minutes before a tsunami generated by a Magnitude 7 earthquake would hit the harbor and cause a seiche that would scour the coastline.
The stealth issue for the Port, however, is fire. During the Autumn and Winter, live-aboards often leave kerosene heaters on in the boat while they are on-shore. Even a small tsunami can lift the boats to such a degree that the mooring lines cause the boats to tilt and tip over the burning kerosene heaters, thus causing the boats to catch fire. It is the nightmare scenario that multiple boats are tipped and the marina at Boat Haven becomes a conflagration – particularly in the dark of winter when it is difficult to see into the dark waters around the boats.
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CONCLUSION Jefferson County is considered one of the most at-risk counties for tsunamis in Washington (Figure TS-12)26.
Figure TS-12 Counties Most At-Risk and Vulnerable to Tsunamis26
Source: Washington State Hazard Mitigation Plan
Tsunami damage can be minimized through land use planning, preparation, and evacuation. Tsunamis tend to impact the same localities over and over again. Therefore, if tsunamis have damaged an area before, they are likely to do so again. One choice is to avoid living in or using areas with significant tsunami hazard. Alternatively, communities can review land use in these areas so that no critical facilities, such as hospitals and police stations, or high occupancy buildings, such as auditoriums or schools, or petroleum-storage tanks are located where there is tsunami hazard.
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If warning is received early enough (two to five hours) which is possible
for tsunamis generated at a distance, preventative action can be taken. People can be evacuated; ships can clear harbors or seek a safe anchorage; equipment and vehicles can be moved; and buildings can be
boarded up and sandbagged. The time from initiation of an earthquake to a tsunami for local earthquakes, however may be only a few minutes to at most a little more than an hour. Residents in areas susceptible to tsunamis should be made aware of the need to seek high ground if they feel strong shaking. Coastal communities should identify evacuation routes even if they do not have good information about potential inundation areas. Standard signs have been adopted for use throughout tsunami prone areas on the west coast. These signs have been posted along highways, beach areas, and campgrounds. Brochures with information on tsunamis have also been provided to these areas.
The U.S. West Coast/Alaska Tsunami Warning Center (WC/ATWC) was established in Palmer, Alaska in 1967 as a direct result of the great Alaskan earthquake that occurred in Prince William Sound on March 27, 1964.
Since 1986, it has taken the Center an average of 10 minutes to get a warning out to potentially affected areas. Messages are composed
automatically based on earthquake location and are sent to National Weather Service (NWS) offices. The NWS offices forward the message to NOAA Weather Radio, the Emergency Alert System, the
Emergency Managers Weather Information Network, and other communication systems available to the public and media.
Coastal areas ranging from Cape Flattery to Long Beach can now receive weather and emergency alert warning information for a radio transmitter site on Mt. Octopus in West Jefferson County. This weather radio site is predicted to help save lives and alert property owners of wind, wave and storm conditions. The Mt. Octopus radio transmitter will also provide residents and
visitors critical warnings in case of tsunamis generated by distant earthquakes in the Pacific area.
Photo by Bob Hamlin
A transmitter, called AHAB (All Hazard Alert Broadcast), installed at the Port Townsend Boat
Haven will also provide information on tsunamis, local weather warnings, and other appropriate emergency warning information for the Port
Townsend area.
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References – TSUNAMI / SEICHE
1. “Tsunami / Seiche”, The Hazard Identification and Risk Assessment (THIRA), Jefferson County Department of Emergency Management, 2011, pp. 38-41. 2. Field trip with Dr. Brian Atwater to South Discovery Bay for the edification of Emergency
Management personnel. Core samples were taken and seven distinctive inundations noted. Circa 2007.
3. Olympic Peninsula Tsunami Inundation Zones at 100’ and 600’, Zetatalk.com, Accessed August 2016. Available at: http://zetatalk.com/ning/06no009.jpg
4. Ibid. 1,38.
5. Ibid. 6. “1700 Cascadia Earthquake”, Wikipedia, Accessed August 2016. Available at: http://en.wikipedia.org/wiki/1700_Cascdia_earthquake
7. “Cascadia Subduction Zone”, Wikipedia, Accessed August 2016.. The following article cited:
Schulz, Kathryn (July 20, 2015). "The Really Big One: An earthquake will destroy a sizable
portion of the coastal Northwest. The question is when.". The New Yorker. Retrieved July 14,
2015.
8. Ibid. The following article cited: Jerry Thompson (13 March 2012). "The Giant, Underestimated
Earthquake Threat to North America". Discover Magazine. Retrieved 15 July 2015.
9. Ibid. The following paper was cited: "The Orphan Tsunami of 1700—Japanese Clues to a Parent
Earthquake in North America" (PDF). Retrieved 2008-05-06. USGS Professional Paper 1707
10. Ibid. “Earthquake Timing”.
11. Ibid. The following paper was cited: Brian F Atwater; Musumi-Rokkaku Satoko; Satake Kenji;
Tsuji Yoshinobu; Ueda Kazue; David K Yamaguchi (2005). The Orphan Tsunami of 1700 —
Japanese Clues to a Parent Earthquake in North America (PDF) (U.S. Geological Survey Professional Paper 1707 ed.).
12. Ibid. The following paper was cited: Brian F Atwater; Martitia P Tuttle; Eugene S Schweig;
Charles M Rubin; David K Yamaguchi; Eileen Hemphill-Haley (2003). "Earthquake Recurrence
Inferred from Paleoseismology" (PDF). Developments in Quaternary Science. Elsevier BV. 1.
Figures 10 and 11 (pp 341, 342); article pp 331-350. doi:10.1016/S1571-0866(03)01015-7. ISSN 1571-0866. Retrieved 2011-03-15.
13. “Tsunami ETA Calculator”, Jefferson County Department of Emergency Management, Accessed
August 2016. Available at: http://www.jeffcoeoc.org/documents/Pacific%20Tsunami%20ETA%20calculations.GIF
14. Risk Report for Jefferson County, including the City of Port Townsend and the Hoh Tribe, FEMA,
WADNR, WAECY, RiskMAP, and Resilienceaction Partners, January 2016, p. 21.
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15. Derived from the South Whidbey Island Fault, Insurance Owl website, accessed August 2016. http://www.insuranceowl.org/wp-content/uploads/2013/11/South-Whidbey-Island-Fault.png
16. “Tsunamis in Washington”, Geological Hazards, Washington Department of Natural Resources website, Accessed August 2016. Available at: http://wa-dnr.s3.amazonaws.com/pictures/ger/ger_tsunamis_overview.png
17. Ibid. 1,39.
18. “Evacuation Routes for Port Townsend and Vicinity”, Washington Department of Natural Resources, Brochure, Accessed August 2016. Available at: http://file.dnr.wa.gov/publications/ger_tsunami_evac_port_townsend.pdf
19. “Hoh Inundation Zones and Evacuation Routes”, Washington Department of Natural Resources, Brochure, Accessed August 2016. Available at: http://file.dnr.wa.gov/publications/ger_tsunami_evac_hoh.pdf
20. “The Village of Queets Inundation Zones and Evacuation Routes”, Washington Department of
Natural Resources, Brochure, Accessed August 2016. Available at: http://file.dnr.wa.gov/publications/ger_tsunamu_evac_queets_general.pdf
21. Risk Report for Jefferson County, including the City of Port Townsend and the Hoh Tribe, FEMA,
WSDNR, WSECY, RiskMAP, and Resilienceaction Partners, January 2016, p.22.
22. Ibid., 23.
23. Ibid.
24. “Port Townsend Inundation Zone – 2015”,by Tim Walsh, Washington Department of Natural Resources, Available at:
http://www.jeffcoeoc.org/documents/Port%20Townsend%20S1%20maximum.JPG 25. “Tohoku Observed Tsunami Heights”, PNSN Outreach, Accessed August 2016. Available at: http://pnsn.org/outreach/hazard-maps-and-scenarios/eq-hazard-maps/tsunami
26. “Counties Most At-Risk and Vulnerable to Tsunamis”, Tsunami Profile, Washington State Hazard
Mitigation Plan, Tab 5.9, September 2012, p. 18. Available at: http://mil.wa.gov/uploads/pdf/HAZ-MIT-PLAN/Tsunami_Hazard_Profile.pdf
Tables - TSUNAMI / SEICHE
TS-1 Recurrence of the “Great Earthquakes” in Washington State TS-2 Building Exposure to a Cascadia M9 Earthquake-generated Tsunami along the Jefferson County Coast
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Figures - TSUNAMI / SEICHE
TS-1 Olympic Peninsula Tsunami Inundation Zones at 100’ and 600’ TS-2 Tsunami ETA Calculator TS-3 South Whidbey Island Fault TS-4 Notable Tsunamis in Washington TS-5 Port Townsend Tsunami Inundation Zone / Evacuation Routes TS-6 Hoh Tsunami Inundation Zone / Evacuation Routes TS-7 Queets Tsunami Inundation Zone / Evacuation Routes TS-8 Inundated Port Townsend Structures for a Cascadia-generated Tsunami (Simulation) TS-9 Inundated Hoh Tribe Structures for a Cascadia-generated Tsunami (Simulation) TS-10 Port Townsend Inundation Zone - 2015 TS-11 Tohoku Japan M9.1 Tsunami Wave Heights TS-12 Counties Most At-Risk and Vulnerable to Tsunamis
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VOLCANIC EVENT / ASH FALL1
SUMMARY
The Hazard: A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.2 The hazard can come in the direct form of molten lava, poisonous and corrosive gases, or rock fragments,
ash fall, and lightning storms that affects people and equipment. Such an opening forms when melted rock from deep within the Earth (magma) blasts through the surface. Washington State has five active volcanoes – Mount Baker, Glacier Peak, Mount Rainier, Mount St. Helens, and Mount Adams.3
Impacts and Effects:
• Loss of life
• Loss of property
• Resultant earthquakes
• Potential clouds of carbon dioxide, toxic gases, and regional acid rains
• Flooding, landslides, avalanches, ash falls
• Damage to mechanical and electronic equipment from fine ash falls
• Damage to critical transportation infrastructure
• Destruction of dams
• Disruption of hydroelectric power sources
• Heavy demands on power supplies as heavy ash falls block out light
• Destruction of stream beds and salmon habitat
• Damage or loss of recreation facilities
• Loss of jobs due to damaged equipment Previous Occurrences: Mount St. Helens has been the only one active in the past 30 years with a massive eruption in 1980, followed by dome building eruptions in the 1980-1986 and 2004-2008.4 It is the last significant volcanic eruption to affect Jefferson County.
Probability of Future Events: Low – Washington’s volcanoes will erupt again, as shown by recent activity at Mount St. Helens. There is a 1 in 500 probability that portions of 2 counties will receive 10 centimeters (4 inches) or more of volcanic ash from any Cascades volcano in any given year, and a 1 in 1,000 probability that parts or all of 3 more counties will receive that quantity of ash5. Due to prevailing westerly winds, the probability of an annual ash-fall from any major Cascade volcano of one centimeter
ranges from 1 in 1000 to 1 in 5000.6 Jefferson County also has risk from ash fall from Alaskan volcanoes because the prevailing westerly winds will carry significant ash towards the county. This is affected greatly by the season and how the Jet Stream is shifted at the time.
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Definition
A volcano is an opening in Earth's surface through which lava (molten rock), hot gases, and rock fragments erupt from the earth’s interior. Such an opening forms when melted rock from deep within Earth (magma) blasts through the surface.
Volcanoes take many forms according to the chemical composition of their magmas and the conditions under which the magmas are erupted. Most volcanoes are mountains, particularly cone-shaped ones,
which were built up around the opening by lava and other materials thrown out during eruptions.
In some eruptions, huge fiery clouds rise over the mountain, and glowing rivers of lava flow down its sides. In other eruptions, red-hot ash and cinders shoot out the mountaintop, and large chunks of hot rock
are blasted high into the air. A few eruptions are so violent they blow the mountain apart.
History of Volcanoes as they Affect Jefferson County7
There are no volcanoes in Jefferson County; however, the proximity to potentially active volcanoes in the Cascade Mountains to the east could impact the county. When Mt. St. Helens erupted on May 18,
1980, heavy ash from a west wind blanketed much of Eastern Washington. Subsequent eruptions on May 25 and June 12 similarly affected Western Washington, although to a lesser degree.
Eruptions of any of the active volcanoes in Western Washington and Oregon could significantly affect travel, tourism and air quality conditions in Jefferson County. During the 1980 eruption, for example, aircraft were diverted from commercial routes downstream because the pumice in the air could damage
engines and possible cause them to quit.8 Figure VO-1 shows eruptions occurring in the Cascade Range during the past 4,000 years9. Figure VO-2 shows volcanos in Alaska and British Columbia. White triangles with an “U” inside designate unmonitored volcanoes, while green triangles designate monitored ones10. Table VO-1 lists the volcanoes on the map in Figure VO-2 and identifies if they are active or not11.
Figure VO-1 Eruptions in the Cascade Range During the Past 4,000 Years9
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Figure VO-2 Alaskan Volcano Map10
Hazard Identification and Vulnerability Assessment
Volcanologists and geologists define Mounts Baker, Rainier, Hood, and St. Helens as active volcanoes. Even Glacier Peak, long thought to have been without an eruption for over 10,000 years is now known to have erupted as recently as a thousand years and possibly as late as the 17th century. Mount Adams is
also capable of renewed activity. Seven separate hazards can be associated with volcanoes. They include earthquakes, lava flows, mud flows, ash flows, rock flows, ejecta, and ash falls. Volcanic hazards can occur with or without an actual eruption. Earthquakes associated with volcanic activity can cause landslides and avalanches in the areas surrounding the actual volcanic sight. With proper wind conditions, ash deposits could be deposited from all of Washington’s volcanoes and from several of those in Oregon. Depending on the size of the eruption and the time of year, the ash could: clog drainage channels; cause electrical short circuits; drift onto roadways; collapse roofs of houses and other buildings, cause skin and eye irritation to the general population and or respiratory distress to the aged, young and infirm; clog engines and air filters, and create acid rain.
In addition, it can disrupt radio, television and telephone transmissions. Since the ash remains on the surface, it can be resuspended in the atmosphere when disrupted by wind or human activities. Heavy ash- fall blots out light. Sudden heavy demand for electric light and air conditioning may cause a drain on power supplies, leading to a partial or full power failure. Under normal wind conditions, the ash would move into eastern Washington. In a south or southeasterly wind, Jefferson County could be affected.
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Table VO-1 Alphabetic List of Alaskan Volcanoes
Below is an alphabetical list of volcanoes. These links will take you to information specific to that volcano. Each volcano has descriptions, images, maps, bibliography, and eruption history.
indicates a volcano is historically active.
indicates a volcano was active in the Holocene.
indicates a volcano has been active within the last 2 million years, but not within the last 10,000 years.
A - G H - Q R - Z
Adagdak
Akutan
Alagogshak
Amak
Amchixtam Chaxsxii
Amukta
Andrew Bay volcano
Aniakchak
Atka
Augustine
Basalt of Gertrude Creek
Behm Canal-Rudyerd Bay
Black Peak
Blue Mtn
Bobrof
Bogoslof
Buldir
Buzzard Creek
Camille Cone
Capital
Carlisle
Chagulak
Chiginagak
Churchill, Mt
Cleveland
Cone 3110
Cone 3601
Dana
Davidof
Denison
Devils Desk
Double Glacier
Douglas
Drum
Duncan Canal
Dutton
Hayes
Herbert
Iliamna
Imuruk Lake Volc Field
Ingakslugwat Hills
Ingenstrem Depression
Volcanic Field
Ingrisarak Mtn
Iron Trig cone
Isanotski
Iskut-Unuk River cones
Jarvis
Jumbo Dome
Kagamil
Kaguyak
Kanaga
Kasatochi
Katmai
Kejulik
Kialagvik
Kiska
Klawasi Group
Knob 1000
Kochilagok Hill
Koniuji
Kookooligit Mountains
Korovin
Koyuk-Buckland volcanics
Kukak
Kupreanof
Little Sitkin
Lone basalt
Lost Jim Cone
Mageik
Makushin
Martin
Rainbow River cone
Recheshnoi
Redoubt
Roundtop
Sanford
Seguam
Segula
Semisopochnoi
Sergief
Shishaldin
Skookum Creek
Snowy
Spurr
St. George volcanic field St. Michael
St. Paul Island
Steller
Stepovak Bay 1
Stepovak Bay 2
Stepovak Bay 3
Stepovak Bay 4
Suemez Island
Table Top Mtn
Takawangha
Tana
Tanada Peak
Tanaga
Tlevak Strait
Togiak volcanics
Trader Mtn
Trident
Ugashik-Peulik
Ukinrek Maars
Uliaga
Ungulungwak Hill-Ingrichuak Hill
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Edgecumbe
Emmons Lake Volcanic Center
Espenberg
Fisher
Folsoms Bluff
Fourpeaked
Frosty
Gareloi
Gas Rocks, the
Gilbert
Gordon
Gosling Cone
Great Sitkin
Griggs
Moffett
Monogenetic QT vents of WWVF
Morzhovoi
Nelson Island
Novarupta
Nunivak Island
Nushkolik Mountain volcanic field
Okmok
Pavlof
Pavlof Sister
Prindle Volcano
Unimak 5270
Unnamed (near Ukinrek Maars)
Veniaminof
Vsevidof
Westdahl
Western Cones
Wide Bay cone
Wrangell
Yantarni
Yunaska
The following chart (Figure VO-3) shows the potential tephra hazard from any major Cascade volcano.12 Under those circumstances, most of Jefferson County would be subject to a Tephra hazard. Tephra is the heated rocks that are shot out of the volcano. Large heavy ones fall close to the volcano; small light ones become the volcanic ash that can float in the air for hundreds, even thousands of miles.
Figure VO-3 Annual Probability of 1 cm or more of Tephra Accumulation from any major Cascade Volcano
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In studying Mount Rainier’s active eruptive history, volcanologists and geologists know that it will erupt
again. Since the exact type and scale of the eruption(s) cannot be predicted, an awareness of the hazards of ash deposits must be communicated to Jefferson County residents. The hazard is considered “low”; however, the potential for eruptions and the potential results remain.
United States Geologic Survey (USGS) volcanologists and Department of Natural Resources (DNR) geologists identify Mount Rainier as being an active eruptive volcano. From the magnitude of past events it is surmised that the consequences of a lahar (mudflow) or debris flow down the populated river valleys near Mount Rainier will be catastrophic and will potentially result in a tremendous loss of life and property. New studies show that the process of geothermal hydroalteration is unevenly weakening the inside of Mount Rainier. This is a process whereby the slopes of the mountain are being internally eaten away by hot, acidic water, which makes the slopes more susceptible for failure, increasing both the
possibility and risk of lahars. Washington State areas including King, Pierce, and Thurston County have much higher risk of loss of life and property than Jefferson County. Jefferson County’s location with respect to the active volcanoes would limit the number of hazards, however impacts would be felt. The economic, cultural and transportation impacts that would be experienced in Jefferson County, however, would be severe if such
an eruption were to occur on Mount Rainier. Most certainly, Interstate 5 and Interstate 90 would be closed, thus disrupting key routes for trade and travel. Ash and some debris could fall on Jefferson County depending on prevailing winds at the time. Jefferson County could serve as a haven for displaced
residents for not only days, but perhaps for decades to come, thus impacting the infrastructure and resources of the County. Puget Sound fishing resources and economic foundations of the timber and recreation industries could be impacted for decades. The tourism industry and economic benefits derived could also be affected for Jefferson County.
Climate Change
It is easy to conclude that volcanoes can disrupt the earth’s climate for reasonably long periods – in human terms. The “Little Ice Age” is said to have been a function of increased volcanism during the periods from 1257-1300 AD and 1400-1455 AD that was sustained for many centuries by sea ice/ocean feedback.13 Now there are theories that volcanism can be stimulated by global warming. The theories, finding new support from research in Iceland, state that superheated rock kept under pressure by the weight of glaciers can become magma when glaciers melt due to global warming and relieve some of the pressure on the rocks. The evidence cited is that glacier melting in Iceland will cause the island nation to rise 1.57 inches per year in the next decade.14 “As the glaciers melt, the pressure on the underlying rocks decreases,” Compton said in an e-mail
to TIME. “Rocks at very high temperatures may stay in their solid phase if the pressure is high enough. As you reduce the pressure, you effectively lower the melting temperature.” The result is a softer, more molten subsurface, which increases the amount of eruptive material lying around and
makes it easier for more deeply buried magma chambers to escape their confinement and blow the whole mess through the surface.15
Iceland is estimated to be losing 11 billion tons of ice weight per year. At the current pace, the researchers predict, the uplift rate in parts of Iceland will rise to 1.57 in. (40 mm) per year by the middle of the next decade, liberating more calderas and leading to one Eyjafjallajökull-scale blow
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every seven years In 2010 the volcanic caldera under the Eyjafjallajökull ice cap in southern Iceland erupted for three weeks from late March to mid-April and spreading ash across vast swaths of
Europe. The continent was socked in for a week, shutting down most commercial flights.16 The idea that reduced ice cover in a volcanic area can actually lead to an increase in volcanism is in
some dispute. The Plan cites a recent article that attributes the cause to reduced ice cover lowering the overburden pressure on magma chambers, softening the magma, leading to more eruptive behavior. However, it is not clear that softer magma under reduced pressure would result in more eruptions. Other scientists have added the idea that reduced pressure would also lead to increased gas production from the liquid magma, thus causing an increase in local chamber pressures.17 However, a mechanism that is well established is that the ejecta from an eruption lead to a temporary globally averaged cooling lasting typically 3 years, depending on the nature of the particles and the altitude to which the eruption projects them. Larger particles precipitate out quickly (days to weeks),
but smaller particles diminish incoming solar radiation and ejected sulfur forms sulfur dioxide which, if it reaches the stratosphere creates sulfuric acid aerosols that also diminish solar radiation. These cooling effects overwhelm the climate-warming effects associated with the volcanic ejection of carbon dioxide, methane and other greenhouse-enhancing gases.18 Research indicates that the Indonesian volcano, Somalas, erupted with a magnitude 7 (out of 8) on the
Volcanic Explosivity Index (VEI) in 1258 C.E., thus causing the medieval “year without summer”.19 This was on the order of magnitude of the Tambora eruption in 1815, and larger than the Krakatoa eruption.
Figure VO-4 illustrates the correlation between the VEI and the volume of ejecta.20 Table VO-2 displays the classification schema for the VEI.21
The net impact of climate change on volcanoes remains in considerable doubt. Increased rates of ice loss driven by climate change are probably not sufficient to cause a marked change in what is already a very sporadic and unpredictable rate of local and regional volcanic activity. However, increases in
more active volcanic areas, particularly Iceland, may increase the likelihood for Jefferson County to be affected by a more globally-felt cooling event. This could have local consequences, both positive and negative, even though the cooling would only last a few years. It is important to note that this
temporary cooling would be followed by a more rapid rate of globally averaged warming as the climate returns to the warming trends established prior to any single volcanic eruption.22
Conclusion Emergency Plans must advise people of potential hazards. Being aware of the potential hazards and responding appropriately will help mitigate the loss of life and could potentially help reduce losses of
property in the eventuality of a volcanic eruption. Emergency plans must be tested and practiced ahead of time and used without hesitation when a volcano threatens to erupt.
Scientists and public officials must announce warnings early and clearly. The Cascades Volcano Observatory in Vancouver, Washington, monitors and assesses hazards from the volcanoes of the Cascade Range of Washington, Oregon, and California. Seismic monitoring is shared with the USGS
center in Menlo Park, California, (for northern California) and the Geophysics Program of the University of Washington in Seattle (for Washington and Oregon). CVO also is home to the Volcano Disaster Assistance Program.
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The Volcano Disaster Assistance Program, home-based in Vancouver, Washington, was formed in the mid-1980s to respond to volcanoes in all parts of the world. An experienced team of USGS and other
scientists can rapidly respond to developing volcanic crises with a state-of-the-art portable cache of monitoring equipment. VDAP has proven to be effective in saving lives and property by assistance provided to local scientists for determining the nature and possible consequences of volcanic unrest and
communicating eruption forecasts and hazard-mitigation information to local authorities.
Figure VO-4 - Volcanic Explosivity Index18
The Volcanic Explosivity Index (VEI) is a relative measure of the explosiveness of volcanic eruptions. It was devised by Chris Newhall of the United States Geological Survey and Stephen Self at the University of Hawaii in 1982.
Volume of products, eruption cloud height, and qualitative observations (using terms ranging from "gentle" to "mega-colossal") are used to determine the explosivity value. The scale is open-ended with the largest volcanoes in history given magnitude 8. A value of 0 is given for non-explosive eruptions, defined as less than 10,000 m3 (350,000 cu ft) of tephra ejected; and 8 representing a mega-colossal explosive eruption that can eject 1.0×1012 m3 (240 cubic miles) of tephra and have a cloud column height of over 20 km (12 mi). The scale is logarithmic, with each interval on the scale representing a tenfold increase in observed ejecta criteria, with the exception of between VEI 0, VEI 1 and VEI 2.
VEI and ejecta volume correlation
Source: Wikipedia
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Table VO-2 – Volcanic Explosivity Classification19
Source: Wikipedia
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References - VOLCANO
1. “Volcano”, The Hazard Identification and Risk Assessment (THIRA), Jefferson County Department of Emergency Management, 2011, pp. 42-44. 2. “Volcano”, Wikipedia, Accessed August 2016. Available at: https://en.wikipedia.org/wiki/Volcano
3. “Volcano Hazard Profile”, Washington State Enhanced Mitigation Plan, Washington Military Department, Emergency Management Division, September 2012, Tab 5.10, p.2. Available at: http://mil.wa.gov/uploads/pdf/HAZ-MIT-PLAN/Volcano_Hazard_Profile.pdf 4. Ibid. 5. Ibid.
6. “Volcano”, Washington State Hazard Identification and Vulnerability Assessment, Washington Military Department, Emergency Management Division, April 2001.
7. “Volcano”, The Hazard Identification and Risk Assessment (THIRA), Jefferson County Department of Emergency Management, 2011, p. 42.
8. Explanation by the pilot of a commercial aircraft to passengers as to why the plane was diverting from a Chicago to Denver trip during the Mount St. Helens eruption.
9. “Volcano Hazard Profile”, Washington State Enhanced Mitigation Plan, Washington Military
Department, Emergency Management Division, September 2012, Tab 5.10, p.3. Available at: http://mil.wa.gov/uploads/pdf/HAZ-MIT-PLAN/Volcano_Hazard_Profile.pdf
10. “Alaskan Volcano Map”, Alaska Volcano Observatory, Accessed August 2016. Available at: https://www.avo.alaska.edu/volcanoes/#-143.297:55.857:4
11. “Alphabetical List of Alaskan Volcanoes”, Alaska Volcano Observatory, Accessed August 2016. Available at: https://www.avo.alaska.edu/volcanoes/#-143.297:55.857:4
12. “Potential Volcanic Hazards from Future Activity of Mount Baker, Washington”, by Cynthia A. Gardner, Kevin M. Scott, C. Dan Miller, Bobbie Meyers, Wes Hildreth, and Patrick T. Pringle, U. S. Geological Survey, 1995, p. 13. Available at: http://pubs.usgs.gov/of/1995/0498/pdf/of95-498_text.pdf 13. Abrupt onset of the Little Ice Age triggered by volcanism and sustained by sea-ice/ocean feedbacks, Gifford h. Miller, Aslaug Geirsdottir, Yafang Zhong, Darren J. Larsen, Bette L. Otto-Bliesner, Marika M. Holland, David A. Bailey, Kurt A. Refsnider, Scott J. Lehman, John R. Southon, Chance Anderson, Helgi Bjornsson, Thorvaldur Thordarson, Geophysical Research Letters, Vol. 39, Issue 2, January 31, 2012. 14. How Climate Change Leads to Volcanoes (Really), Jeffrey Kluger, Time.com, January 29, 2015. Accessed September 2016. Available at: http://time.com/3687893/volcanoes-climate-change/ 15. Ibid. 16. Ibid.
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17. Comments on the Jefferson County Hazard Mitigation Plan, by Robert Bindschadler (NASA Emeritus Scientist) and Cindy Jayne, Email to Hazard Mitigation Plan Project Coordinator, January 6, 2017, p.4. 18. Ibid.
19. Indonesia’s Somalas Volcano Kick-Started Little Ice Age, Research Suggests, by Carolyn Gramling, The Huffington Post, 10/02/2013. Accessed September 2016. Available at: http://www.huffingtonpost.com/2013/10/02/somalas-volcano-little-ice-age_n_4029092.html 20. Volcanic Explosivity Index, Wikipedia, Accessed September 2016. Available at: https://en.wikipedia.org/wiki/Volcanic_Explosivity_Index#Classification
21. Ibid. 22. Ibid. 17,5.
Tables - VOLCANO
VO-1 Alphabetical List of Alaskan Volcanoes VO-2 Volcanic Explosivity Classification
Figures - VOLCANO
VO-1 Eruptions in the Cascade Range During the Past 4,000 Years VO-2 Alaska Volcano Map VO-3 Total Cascade Tephra Hazards
VO-4 Volcanic Explosivity Index
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WILDFIRE / FOREST / URBAN INTERFACE1
SUMMARY The Hazard: Forest and wildland fires are the uncontrolled destruction of forested and wild lands by fire caused by natural or human-made events. Forest and wildland fires occur primarily in undeveloped areas, although there are significant pockets of residences within Jefferson County woodlands2. Impacts and Effects:
• Loss of civilian lives and firefighters
• Loss of homes and businesses
• Loss of crops and livestock
• Destruction of wildlife habitat and watersheds
• Damage to salmon habitat
• Damage or total loss of scenic vistas and recreation facilities
• Destruction of timber resources
• Loss of jobs due to destroyed and damaged equipment and facilities
• Decreased tourism
• High costs to fight fires
• Fire and emergency response teams unable to meet “routine” obligations and fight wildland fires
simultaneously
• Vulnerability to flooding increases Previous Occurrences: According to the National Fire Information Reporting System (NFIRS), Jefferson County averages 5 – 10 acres of wildland fires every year. The last major wildfire, the Chimney Peak fire, occurred in 1981
Probability of Future Events: High – An annually recurring dry season combined with encroaching residential development is resulting in a regular brush fire season. So far, the rapid response of rural fire departments has kept the impact of these fires to a minimum.
Definition
Forest and wildland fires are the uncontrolled destruction of forested and wild lands by fire caused by
natural or human-made events. Forest and wildland fires occur primarily in undeveloped areas. Interface fires are a recent phenomenon that occurs in developed forest and wildlands, only partially
cleared, and occupied by structural development. In interface fires people, homes and small businesses intermingle with the wildland and forest areas.
When weather conditions are dry and fuels are abundant, rapidly spreading fires can cause significant loss of life and property.
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History of Fires as it Affects Jefferson County
Jefferson County has had an active history of wildland fires during the past millennium. The fact that the oldest of old-growth timber stands are rare attests to the fact that most of the area has burned and re-
burned many times during the past 1000 years. Stands of trees older than 500 years do not occur except in small patches or scattered trees found in moist draws and stream bottoms at the headwaters of a few creeks and rivers. It is difficult to trace the fire history of this area back more than 350 years. However, old-growth trees and fire scars suggest fires about 450, 480, 540 and 670 years ago. Historically, wildland fires were not
considered a hazard. Fire is a normal part of most forest and range ecosystems. Fires historically burned on a fairly regular cycle.
The burning cycle in western Washington appears to be about every 100 – 150 years. A preponderance of evidence, however, has been obliterated by logging, major windstorms that toppled older trees, and more recent fires in the areas. Recorded history of fires in the area, however, indicates Jefferson County
has had an active history of fires. As communities expand farther and farther into forested lands, and the desire to maintain the wilderness ambiance, interface fires are becoming a significant hazard, having the potential for loss of life and destruction of property.
“The occurrence of wildfires on the Olympic peninsula is closely tied to climate. It appears that the pattern of fires has been as variable as the pattern of past climates. Some periods have had stand destroying fires, others have had almost none. Still other periods may have had a pattern of high fire frequency but low fire intensity. Because of this variability and the many factors involved, one aspect of the fire history of the Olympics seems certain: one cannot characterize the fire patterns of one period by knowing what it is in another.3” Table WF-1, below, details some of the history and more interesting wildland fires that have affected Jefferson County.
Table WF-1 Representative Wildland Fires That Affected Jefferson County
Date Identifier Particulars
7200 – 8700 years
ago Lower Hoh River Drainage Layer of charcoal underneath
dated 6800 year old ash4.
~1308 Olympic Peninsula
At the end of the Medieval
Optimum and start of the Little Ice
Age; burned half of the Olympic
Peninsula5.
~1448 - 1538 Mid-elevations of the Olympic
Peninsula6
~1668 & 1701 Last of the Big Fires Burned over one million acres7.
~1720 - 1850 Virtually no fires. End of Little Ice Age; Climate cool
and wet8.
Sept 1864 Ludlow – Quilcene Fire
Several thousand acres on Mt.
Walker, Mt. Turner, and Quilcene
Ridge fanned by a high east wind9.
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Date Identifier Particulars
1868 Multiple smaller fires.
Drought was severe. Driest June,
July, August and September for the
58-year record up to that time.
Worst fire season since early
1700’s10.
1885 Neilton Burn 2000 acres near Lake Quinault11.
1890 Quilcene Fire
Land clearing burns near Sequim
got out of control. Fire survived the
winter smoldering in stumps.
Restarted in in the spring and
burned south, covering 30,000
acres12.
1902 The Forest Fires of 1902
Many fires in Washington and
Oregon. One fire or series of fires
followed the Washington coast,
jumping the Quinault, Raft, Queets,
Clearwater, Hoh, Quillayute rivers,
and swung around Lake Ozette and
died out before it reached the
Sooes13. The worst fire season in
275 years; worse than the 1868
season14.
1918 Dosewallips & Duckabush Fires15 Dosewallips Fire – 2665 acres
Duckabush Fire – 4810 acres
1924-1925 Green Mountain, Mt. Zion, Snow
Creek Fires16
Discovery Bay (1924) 5000 acres
Snow Creek Fire (1924) 3100 acres
Green Mt. Fire (1925) 9615 acres
Snow Creek Fire (1925) 3825 acres
1929 Interorrem Fire 85 Lightning strikes; 8,602 acres in
the lower Duckabush drainage.17
1939 Deep Creek Fire 13,000 acres of which 3460 were in
the Olympic National Forest18
1978 Hoh Fire
Caused by Lightening. Discovered
13 days after ignition in Olympic
National Forest; 1,050 Acres19
1981 Chimney Fire 500+ Acres20
August 2015 Sunnyside Road, Mason County
59 acres along a power corridor.
Threatened BPA transmission line;
cuts power to more than 2000
Jefferson County PUD customers21.
August 2016 Olympic Forest Fires Four separate fires totaling 956
acres as of August 22nd, 201622.
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Hazard Identification and Vulnerability Assessment
The Washington Department of Natural Resources and its federal and local partners determined that 181 communities are at high risk for wilderness fires after evaluating them for fire behavior potential, fire
protection capability, and risk to social, cultural and community resources. Risk factors included area fire history, type and density of vegetative fuels, extreme weather conditions, topography, number and density of structures and their distance from fuels, location of municipal watershed, and likely loss of housing or business. The evaluation used the criteria in the wildfire hazard severity analysis of the National Fire Protection Association’s NFPA 299 Standard for Protection of Life and Property from Wildfire, 1997 Edition. Figure WF-1 shows the areas at high risk for fires within each county.23
Figure WF-1 Areas of High Fire Risk (2002)23
As seen from the map preceding, Jefferson County is among the counties in which the wildfire threat is
high. Jefferson County communities that are on the list of areas at high risk for urban interface wildfires are: Brinnon, Port Hadlock, Port Townsend, and Quilcene. In 2016, however, the focus of the WA DNR is on the Wildland Urban Interface Communities at risk based on a statistical mean return rate for fires, which excludes Jefferson County communities that are in
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rural areas. Figure WF-2 shows the LandFire Mean Fire Return Interval throughout the state. East Jefferson county is yellow, which is “71-80 years.24” This is underscored by the apocryphal joking of
local firefighters that the Olympic Peninsula is known as the “Silicon Forest” – not because of technology companies, but rather because it will not burn.
Figure WF-2 LANDFIRE Mean Fire Return Interval24
The uncomfortable fact is that Jefferson County and its populated communities are integrated with the surrounding forest. Wildland – Urban Interfaces (WUI) exist in a multiplicity of areas because
Homeowners Associations, developers, etc. carve out communities while leaving extensive trees among and around the dwellings. The Mean Fire Return Interval is meaningless because increasingly forest fires are caused by human carelessness and can override natural checks and balances. Meanwhile, because of
historical reasons, the ownership of DNR protected land is a checkerboard with privately own land, thus making it vulnerable to fires started on private lands. Figure WF-3, below, is a google earth view of the City of Port Townsend to show how the wildland-urban interface is intermixed throughout the City.25
Table WF-2, below, is a gallery of recent WUI fires that impacted Jefferson County.
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Figure WF-3 - Wildland – Urban Interface throughout Port Townsend25
The city is on a peninsula with the city limits being at Jacob Miller Road, which is labeled on the left side of the
map.
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Table WF-2 Gallery of Selected Recent Jefferson County WUI Fires
08/20/2016 Recreational Fire Leads to Wildfire.
“East Jefferson Fire Rescue
crews at 7:50 a.m. Saturday,
Aug. 20 responded to a brush
fire, 15 by 20 feet in size, in
the 400 block of Four Corners Road. Neighbors
stated that a man had been
burning Friday night in a
homemade, half-barrel
fireplace, which was found
within the burn area,
according to EJFR.
Investigators believe a spark
from that barrel ignited the
brush fire.“ Courtesy photo
by Bill Beezley, East Jefferson
Fire Rescue26.
09/02/2015 Fire in Mason County Cuts Electric Service to Over 2000 Jefferson County Customers.
“More than 2,000 electricity
customers in Jefferson
County were without power
on Thursday, Aug. 28 as a
result of two separate
incidents, including a wildfire
under a Bonneville Power
Administration (BPA)
transmission line in Mason
County.
The Sunnyside Road Fire,
which is on state Department
of Natural Resources (DNR)
land, had consumed about
59 acres in the Skokomish
Valley as of Monday, Aug. 31,
according to Joe Miles, a
spokesperson for DNR.
Multiple agencies responded to fight the blaze; 68
personnel battled the fire,
which as of Monday was
contained. Cause of the fire
is still unknown.” By Leader
Staff27.
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Beckett Point Fire – 09/05/2011
“Firefighters on Sept. 5 kept
this fireworks-induced
wildfire from reaching homes
on Beckett Point (the sea-
level cabin community’s
southern edge, which is to
the right) and the homes
tucked into the tree line
along Beckett Point Road.
The fire started at about 3
p.m. on Monday, a result of
kids playing with fireworks.
Fickle winds fanned it to
about 21 acres. It was 70
percent contained by 7 p.m. (This was the fire’s calm
section.) Soon after, a
helicopter began dropping
water along ridge-top brush
and trees.” Photo by James
Robinson28
Jefferson County and Port Townsend are served by 5 active fire districts, all with mutual aid agreements. During any fire incident, the incident commander can ask for units from any of the districts. At such times, units not involved redeploy to cover the areas left exposed by units fighting the wildfire. This
“floating battalion” allows all of the districts to put more equipment on a fire and still have coverage in their home district. In the Beckett Point fire, for example, engines from three districts responded directly to the fire, Jefferson County Emergency Management set up an Incident Command Post for communications at the fire, and mutual aid partners extended coverage to those districts whose equipment responded to the fire. Jefferson County’s fire season usually runs from mid-May through October. Any prolonged period without significant precipitation presents a potentially dangerous situation, particularly if strong dry, east winds prevail. The probability of a forest fire or an interface fire in any one location depends on fuel conditions, topography, the time of year, the past weather conditions, and if there is human activity such as debris burning, camping, etc., which are taking place.
The combination of a dryer climate along with a plethora of illegal meth labs hidden in the wildlands has resulted in an increase the number and severity of urban interface fires. In addition, as the buildable space
in the towns and city are used up, numerous housing developments are being created in the unincorporated portion of the county.
Washington State fires responded to by city and county fire departments were largely started by human causes. Included in the list of human causes are cigarettes, fireworks, and outdoor burning. Wildland fires started by heat spark ember of flames caused the largest dollar loss, followed by debris burning and cigarettes. Loss per incident for debris fires is three times higher than any other fire cause.
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Short-term loss caused by fires is the complete destruction of valuable resources such as timber, wildlife, habitat, scenic vistas, and watersheds. Vulnerability to flooding increases due to the destruction of
watersheds. Long-term effects are reduced amounts of timber for building and recreation areas. Home building near forests and wildlands increases the loss from fires. There is a trend for families to
move into more rural and forested areas. Many homes are built with an effort to maintain the scenic aspects of the surrounding area. These areas are farther from firefighting assets. Frequently, there is little clearance of vegetation resulting in a lack of defensible space.
09/05/2011 On Sept. 5th firefighters came over the ridge to keep flames from reaching the houses on the ridge overlooking Beckett Point. Photo by James Robinson of the Leader
Narrow access roads frequently found in these areas interfere with fire suppression efforts. Frequently roads are so narrow that standard sized fire apparatus cannot adequately turn around or pass on the roads. More diverse fire apparatus such as brush rigs and smaller engines are needed. Smaller fire districts may not be able to financially support these additional requirements.
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Climate Change
“The Olympic Mountains are generally wetter than other parts of the state and have been less
prone to wildfires. However, it is expected that warmer summer temperatures, higher evaporation rates, and declines in soil moisture will increase wildfire risk on the Peninsula29. The fire season will also lengthen due primarily to earlier snowmelt. One set of projections expects a 150% -
1,000% increase in annual area burned in forests west of the Cascades by the end of the century30. When it comes to wildfire, the risk to property and people is determined primarily by the amount of development along the wildland/urban interface. In both Jefferson and Clallam County 24% of
that interface is developed31 and this includes 14,686 homes in Clallam County and 10,475 homes in Jefferson County (in 2013).32”
Conclusion
Jefferson County, the City of Port Townsend, and the unincorporated towns of Brinnon, Port Hadlock, and Quilcene are all considered at high risk for urban interface wildfire – at least by the local fire districts.
The commingling of residential enclaves adjacent to and among forested areas also means that these areas are highly vulnerable. A number of activities can be undertaken which will reduce the actual numbers of fires and resulting loss of fires.
• Forest fire education and enforcement programs must be emphasized to include early
reporting of fires
• Effective early fire detection and emergency communication systems are essential
• Effective early warning systems are essential to notify local inhabitants and persons in the
area of the fire. An evacuation plan detailing primary and alternate escape routes should be
developed if possible.
• Fire-safe development planning should be undertaken by jurisdictions to include:
- Sufficient fuel free areas around structures - Fire resistant roofing materials
- Adequate two-way routes and turnaround areas for emergency vehicles - An adequate water supply - Development of local ordinances to control human caused fires
• Road closures should be increased during peak fire periods to reduce access to fire prone
areas
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References – WILDFIRE (Forest – Urban Interface)
1. “Wildland / Forest / Interface Fires”, The Hazard Identification and Risk Assessment (THIRA), Jefferson County Department of Emergency Management, 2011, pp. 45-47. 2. Ibid., 45. 3. Olympic Peninsula Fire History, Lake Cushman Community Wildfire Protection Plan, Lake Cushman Community Members, Olympic National Park, Wa Department of Natural Resources, Mason County Fire Marshall, Mason County Fire District 18, 2006, p. 3. 4. Ibid. 5. Ibid. 6. Ibid.
7. Ibid., 4. 8. Ibid. 9. Ibid.
10. Ibid. 11. Ibid.
12. Ibid.
13. William G. Morris, "The Great Fires of 1902," extracted from "Forest Fires in Western Oregon and Western Washington," Oregon Historical Quarterly. XXXV (1934) p. 333-337. Available at: http://search.tacomapubliclibrary.org/unsettling/unsettled.asp?load=Forest+Fire+of+1902&f=disaster\firesfor.902 14. Edwin Van Syckle, "When nature turned mean," Seattle: Pacific Search Press, 1980. p. 192-195. 15. Ibid. 3,4. 16. Ibid. 3,5. 17. Ibid. 18. Ibid. 19. “Fire History”, Olympic National Park Website, Accessed August 2016. Available at: https://www.nps.gov/olym/learn/nature/firehistory.htm 20. Ibid. 21. “Sunnyside Fire Update 9/3/2015”, MasonWebTV.com, Accessed August 22, 2016. Available at: http://masonwebtv.com/archives/16905 22. Olympic National Park Fires 2016, InciWeb Incident Information System, Accessed 8/22/2016. Available at: http://inciweb.nwcg.gov/incident/4906/
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23. Progress Report on the National Fire Plan in Washington State, Washington Department of Natural Resources, September 2002. 24. Figure 5.5-11 Washington Department of Natural Resources, (DNR) 2014, “Wildland Fire Hazard Profile”, Washington State Hazard Mitigation Plan, Washington State Military Department, Emergency Management Division, September 2014, Tab 5.5, p. 20. Available at:
http://mil.wa.gov/uploads/pdf/wildland_fire_hazard_profile_2014-update.pdf 25. Wildland – Urban Interface throughout Port Townsend, by Ken Horvath, Jefferson County Department of Emergency Management, Jefferson County, Washington, September 16, 2016 26. “Recreational Fire Leads to Wildfire”, Photo by Bill Beezley, East Jefferson Fire Rescue,
Published by The Port Townsend Leader, 08/20/2016. Available at: http://www.ptleader.com/news/photo-recreational-fire-leads-to-brush-fire/image_ac9b708c-66f8-11e6-af32-0f5915d0a018.html 27. “Fire in Mason County cuts electric service to 1,607 Jefferson County customers”, by Leader Staff, Published by The Port Townsend Leader, 09/02/2015. Submitted photo. Available at:
http://www.ptleader.com/news/fire-in-mason-county-cuts-electric-service-to-jefferson-county/article_e27e63ac-50fc-11e5-8327-7f59cd89d9ba.html 28. “Suppression efforts continue at Beckett Point fire…” by James Robinson of the Leader, Published by The Port Townsend Leader, 09/05/2011. Available at: http://www.ptleader.com/news/fire-update-suppression-efforts-continue-at-the-beckett-point-
fire/article_9f4a3f65-1403-5b41-90d5-b7fd7e509e14.html 29. University of Washington, Climate Impacts Group, 2013. Climate Change Impacts and Adaptation in Washington State: Technical Summaries for Decision Makers. http://cses.washington.edu/cig/reports.shtml
30. Ibid. 31. Headwaters Economics, 2013, As Wildland Urban Interface (WUI) Develops, Firefighting Costs Will Soar. Available: http://headwaterseconomics.org/dataviz/wui-development-and-wildfire-costs
32. Petersen, S., Bell, J., Miller, I., Jayne, C., Dean, K., Fougerat, M., 2015. Climate Change Preparedness Plan for the North Olympic Peninsula. A Project of the North Olympic Peninsula Resource Conservation & Development Council and the Washington Department of Commerce, funded by the Environmental Protection Agency. p. 57. Available:
www.noprcd.org Tables - WILDFIRE (Forest – Urban Interface)
WF-1 Representative Wildland Fires That Affected Jefferson County WF-2 Gallery of Selected Recent Jefferson County WUI Fires
Figures - WILDFIRE (Forest – Urban Interface)
WF-1 Areas of High Fire Risk (2002) WF-2 LandFire Mean Fire Return Interval – 2014
WF-3 Wildland – Urban Interface throughout Port Townsend
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WINTER STORM1
SUMMARY The Hazard: The National Weather Service defines a winter storm as having significant snowfall, ice, and/or freezing rain; the quantity of precipitation varies by elevation2. Heavy snowfall is 4 inches or more in a 12-hour period, or 6 inches or more in a 24-hour period in non-mountainous areas; and 12 inches or
more in a 12-hour period or 18 inches or more in a 24-hour period in mountainous areas3.
Impacts and Effects:
• Loss of life
• Damage to homes and businesses
• Damage to critical transportation infrastructure
• Loss of timber resources
• Emergency responses are delayed
• Damage or loss of recreation facilities
• Disruption of utilities
• Loss of jobs due to damaged equipment and facilities
• School closures
• Business closures resulting in economic impacts Previous Occurrences: Although Jefferson County gets a few days of snow every year, the last snow
storm justifying a disaster declaration was in December, 1955. In 1991, the area received an “Arctic
Express Blizzard”. Disaster declarations were made for severe winter storms in 2006 and 2007, but these were primarily due to wind, flooding and mudslides. In 2009, snow storms set record levels, thus resulting in Public Assistance (PA) being made available due to extraordinary costs of snow removal incurred by municipalities. Probability of Future Events: High – The State of Washington Hazard Mitigation Plan puts the probability of a severe winter storm in Jefferson County at “125%” – intending to mean that the county experiences more than one storm every year4. Most of the time, it manifests as damaging winds and rain, although it can be as ice or snow.
History of Severe Winter Storms Affecting Jefferson County
Most storms move into Washington from the Pacific Ocean with a southwest to northeast airflow. Maritime air reaching the Olympic Mountains rises upwards and cools. As this airflow reaches higher elevations and cools, there is less ability to hold moisture and precipitation occurs.
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Jefferson County is subject to several severe local storms each year. These storms have
included high wind, snow, ice, rain, and hail. Snowstorms or blizzards are the most likely and potentially devastating phenomena, with
the ability to isolate people from emergency services and to interrupt utility services and other lifelines. In 1996-1997, snowstorms were also associated with other natural hazards such as flooding and landslides. Ice storms can occur when rain falls out of the warm moist upper layer atmosphere into a dry layer with freezing or sub-freezing air near the ground. Rain freezes on contact with the cold ground and accumulates on exposed surfaces – as illustrated by Figure WS-1, a frozen Haller
Fountain6. Snow Storms – Winter Storm – The National Weather Service defines a winter storm as having significant snowfall, ice, and/or freezing rain; the quantity of precipitation varies by elevation. Heavy snowfall is 4 inches or more in a 12-hour period, or 6 inches or more in a 24-hour period in non-mountainous
areas; and 12 inches or more in a 12-hour period or 18 inches or more in a 24-hour period in mountainous areas7. Figure WS-2 shows Port Townsend after 12” of snow fell in a single day in 19558. Areas most vulnerable to winter storms are those affected by convergence of dry, cold air from the interior of the North American continent, and warm, moist air off the Pacific Ocean. Typically, significant winter
storms occur during the transition between cold and warm periods. Counties considered most vulnerable to winter storm are 1) those most affected by conditions that lead to such storms, as described above, and 2) those with a recurrence rate of 50 percent, meaning the county experiences at least one damaging winter storm event every two years. If damaging wind storms are separated out, Jefferson County does not meet that criteria.
HAZARD IDENTIFICATION AND VULNERABILITY ASSESSMENT
All areas of the County are vulnerable to various severe local storms. Western Washington has had an average of 11.4 inches of snowfall annually over the past 30 years. Windstorms generally occur between October and April as well. Power outages are common as a result of these storms. Road travel is often treacherous due to snow, ice, and fallen trees. As a result, schools are often closed and local businesses are impacted. Emergency responses can be delayed.
The general effects of most severe local storms are immobility and loss of electrical power and telephone service. Physical damage to homes and businesses can occur from wind damage, accumulation of snow,
History of Storms Affecting Jefferson County’s People and Economic Activity5
1940 - High Winds (Tacoma Narrows Bridge blown down) 1950 – Blizzard 1961 – Snowstorm 1962 – Columbus Day Storm 1964 – Snowstorms 1979 – High Winds & Rain (Hood Canal Bridge destroyed) 1981 – Windstorm 1991 – Arctic Express Blizzard 1993 – Inauguration Day Windstorm 1995 – Wind and rainstorms 1997 – Snow, wind and snowmelt 2003 – Severe Storm & flooding 2006 – Severe winter storm, landslides & mudslides 2007 – Severe storm, flooding, landslides & mudslides 2009 – Severe winter storm, landslides, mudslides and flooding 2009 – Severe winter storm with record and near-record snow
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ice, and hail. Even a small accumulation of snow can wreak havoc on transportation systems due to a lack of snow clearing equipment and experienced drivers.
If damaging wind storms are included in the winter storms, Jefferson County is considered among the
most vulnerable to storms. Counties considered most vulnerable to high winds are 1) those most affected
by conditions that lead to high winds, as described above, and 2) those with a high wind recurrence rate of 100 percent, meaning the county experiences at least one damaging high wind event every year. Counties that meet both criteria are highlighted in Figure WS-3, below9.
Figure WS-3 - Counties Most Vulnerable to High Winds9
Source: WA State Hazard Mitigation Plan
Jefferson County is considered among the most vulnerable to high winds because it is affected by conditions leading to high winds, and has a recurrence rate of “125%”. A recurrence rate greater than
100% means that Jefferson County has more than one damaging wind storm a year. If damaging winds are excluded from the winter storms, Jefferson County is not considered vulnerable
to winter storms. Areas most vulnerable to winter storms are those affected by convergence of dry, cold air from the interior of the North American continent, and warm, moist air off the Pacific Ocean. Typically, significant winter storms occur during the transition between cold and warm periods.
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Counties considered most vulnerable to winter storm are 1) those most affected by conditions that lead to such storms, as described above, and 2) those with a recurrence rate of 50 percent, meaning the county
experiences at least one damaging winter storm event every two years. Figure WS-4 highlights the counties that meet that criteria10.
Figure WS-4 - Counties Most Vulnerable to Winter Storms10
Source: WA Hazard Mitigation Plan Table WS-1, “Severe Winter Storms Affecting Western Washington”, details the significant winter storms that have impacted Jefferson County.11 It includes both those that were declared emergencies and those
that were of significance, but were not declared, either because it was before declarations were available as a tool or because they did not meet the criteria for a national declaration.
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Figure WS-1: Ice dresses up Haller Fountain in Port Townsend on an unusually cold day.6
Source: Port Townsend An Illustrated History…
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Figure WS-2 - Port Townsend’s Water Street in 19558
Source: Port Townsend An Illustrated History…
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Table WS-1 - Severe Winter Storms Affecting Western Washington11
(Disaster Declaration Number in Italics if Jefferson County was Included.)
Date Storm Type Description
January 6, 1880 Major Snow Storm Major Snow Storm; 4 feet of snow; drifts up to 10 feet
high.
January 1893 Major Snow Storm Major Snow Storm
February 3,
1916
Snowstorm
and wind
Thirty point five inches of snow fell in 24 hours and 2 to
4 feet in other parts of Western Washington. In January
and February Seattle received 58 inches of snow
December 25,
1919
Major Snow Storm
November 7,
1940
Wind
Tacoma Narrows Bridge collapsed due to induced
vibrations from 40 miles per hour winds.
January 1950
Snowstorm
and wind
Blizzard dumped 21 inches of snow on Seattle and killed
13 people in the Puget Sound region. The winter of
1949-50 was the coldest recorded in Seattle with
average temperatures of 34.4 degrees.
December 22,
1955
Snowstorm Twelve inches of snow in Port Townsend.
November
1958
Wind
High winds in Western Washington.
October 1962
Columbus Day Wind
Storm
(Maj #137)
Columbus Day Storm struck from northern California to
British Columbia and is the windstorm to which all
others are compared. Recorded winds gusts were 150
miles per hour in Naselle, 100 in Renton, 92 in
Bellingham and Vancouver, and 88 in Tacoma. Federal
disaster number 137 was assigned for the event.
December 28-29
1968
Major Ice Storm
February
1979
Wind
Hood Canal Bridge destroyed by windstorm.
December 1979 Major Winter Storms (Maj. 612) Storms/ high tides / mudslides / flooding
November
1981
Wind
High winds in Western and Eastern Washington.
January 1986 Major Winter Storm (Maj. #757) - Severe storms / flooding
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November
1990
Severe Wind and
flooding
(Maj. #883) The Lake Washington floating bridge sank,
killing two and causing $250 million in damages.
January 20,
1993
Wind
Inauguration Day Storm damaged homes, businesses,
and public utilities leaving thousands without power for
days from Longview to Bellingham. The state EOC
coordinated resources. The National Guard provided
generator power and equipment. The Energy Office
priorities power restoration. The American Red Cross
sheltered 600 people and fed 3,200 meals. Department
of Transportation and State Patrol coordinated
transportation routes and road closures. Federal
Disaster Number 981 was assigned for the event.
November -
December
1995
Rain, flood,
and wind
(Maj. #1079) Storms, starting in California generated
winds of 100 miles per hour, continued north causing
three states, including Washington, to issue disaster
proclamations. Federal Disaster Number 1079 was
issued for the incident.
February 7,
1996
Rain and
flood
The Washington State Emergency Operations Center
(EOC) activated to handle severe floods covering state.
These were considered the most destructive and costly
in state history and 19 counties were covered under a
Presidential disaster declaration. Three people were
killed. Total damages were estimated at $400 million,
an estimated 691 homes destroyed and 4,564 damaged.
The EOC remained activated through February 23.
Federal Disaster Number 1100 was issued for the
incident.
April 24,
1996
Rain, flood,
and wind
The state EOC activated because the state was covered
with flooding rivers and high wind warnings. Six
counties declared states of emergency. The EOC
remained activated until April 25.
November 19,
1996
Ice storm The state EOC activated in response to storm conditions
around the state. The city of Spokane and Spokane
County declared an emergency, and 100,000 customers
were without power for nearly two weeks. In Puget
Sound 50,000 customers were without power as well as
thousand others across the state. There were 4 deaths
and $22 million in damages. The EOC remained
activated until December 1. Federal Disaster Number
1152 was issued for the storm.
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December 4,
1996
Winter storm,
ice, wind, and
gale warning
The state EOC activated in response to storms rushing
across the state, which caused road closures and power
outages. Pend Oreille County declared an emergency
because of snow and power outages. The Governor
proclaimed emergencies for Pend Oreille and Spokane
Counties. The EOC remained activated until December
5. This storm was part of Federal Disaster Number
1152.
December 26,
1996
Winter storm,
wind, gale
warning,
flood,
landslide, and
avalanche
(Maj. #1159) The state EOC activated in response to
storm fronts pushing across the state causing structures
to collapse under the heavy weight of snow, road
closures, power outages, landslides, and 20 weather
related deaths. The Governor declared emergencies for
37 counties - only Douglas and Franklin Counties were
not included. The Washington National Guard had 110
personnel on active duty. The EOC remained activated
until January 15, 1997. Federal Disaster Number 1159
was issued for the storm.
January 31,
1997
Rain and
flood
The state EOC activated in response to lowland floods in
Walla Walla, Asotin, and Columbia Counties. Flood
warnings were in effect for Klickitat and Columbia
Rivers. The EOC remained activated until February 1.
This incident was part of Federal Disaster Number 1159.
March 18,
1997
Rain and
flood
(Maj. #1172) The state EOC activated in response to
widespread flooding throughout Washington State and
remained activated until March 26.
October 29,
1997
Rain and wind Heavy rain and gusty winds passed over the state on
October 29 especially the southern Cascade Range. The
EOC activated on October 30 in response to floods.
Flood warnings were in effect for 11 Western
Washington rivers and watches for all rivers in five
western counties. The EOC remained activated until
October 31.
January 11,
1998
Winter storm
and flood
The state EOC activated on January 14 in response to
storms affecting Lewis, Mason, Thurston, and Pierce
Counties. The EOC remained activated until January 19.
November 19,
1998
Winter storm The state EOC activated for problems associated with
forecast high winds. Winds of 80 miles per hour were
recorded toppling trees and causing power outages to
15,000 customers. The EOC remained activated until
November 23.
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December 29,
1998
Winter storm
The state EOC activated in response to flooding threat
caused by heavy rain and mountain snow melt. Stevens
and Snoqualmie passes were closed due to avalanche
hazard. Stranded holiday travelers unable to go over
Snoqualmie Pass caused Kittitas County to declare an
emergency. Nisqually river flooding caused evacuation
of 45 residents of a McKenna nursing home. In
Cathlamet, 400 residents were without water causing
Wahkiakum County to declare an emergency. Pullman
declared an emergency because of flooding. The EOC
remained activated until December 31.
October 27,
1999
Wind
A strong Pacific frontal system moved across
Washington causing power and phone outages. Marine
storm and coastal flood warnings were issued for the
coast. One citizen died when a tree fell on them. The
EOC remained activated until March 28.
November 9,
1999
Rain and
flood
The state EOC activated on November 12 because of
weather conditions in Western Washington. The Skagit
River rose to six feet above flood stage. Flooding was
most severe in Hamilton. Two shelters were opened for
evacuees. The EOC remained activated until November
13.
December 14,
1999
Rain and
flood
The state EOC activated on December 15 in response to
widespread flooding in Western Washington. A tropical
weather system brought in heavy rain and caused
snowmelt and flooding. Emergency declarations were
issued in Grays Harbor, Jefferson, Skamania, and
Wahkiakum Counties. Sixteen counties were impacted
by the weather system. The EOC remained activated
until December 18.
October 2003 Severe Storms and
Flooding
(DR 1499) - Chelan, Clallam, Grays Harbor, Island,
Jefferson, King, Kitsap, Mason, Okanogan, Pierce, San
Juan, Skagit, Snohomish, Thurston, and Whatcom
Counties
January 27 to
February 4,
2006
Severe Storms,
Flooding, Tidal Surge,
Landslides, and
Mudslides
(DR 1641) - Clallam, Grays Harbor, Island, Jefferson,
Kitsap, Mason, Pacific, Pend Oreille, San Juan,
Snohomish, and Wahkiakum Counties
November 2-11,
2006
Severe Storms,
Flooding, Landslides,
and Mudslides
(DR 1671) - All counties in the State of Washington are
eligible to apply for assistance under the Hazard
Mitigation Grant Program.
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December 14-
15, 2006
Severe Winter Storm,
Landslides, and
Mudslides
(DR 1682) - All counties in the State of Washington are
eligible to apply for assistance under the Hazard
Mitigation Grant Program
December 1 -
17, 2007
Severe Storms and
Flooding
(DR 1743) - Clallam, Grays Harbor, Jefferson, King,
Kitsap, Lewis, Mason, Pacific, Skagit, Snohomish,
Thurston and Wahkiakum Counties
December 2008
/ January 2009
Severe Winter Storm,
Flooding, Landslides,
& Mudslides. Record
Snowfall
(DR1817) Public Assistance made available to Jefferson
County and the City of Port Townsend because of
extraordinary costs of snow removal.
March 2009 Severe Winter Storm (DR1825) Severe Winter Storm and Record and Near Record
Snow
October 2015 Severe Windstorm (DR4242) Severe Windstorm
January 2016 Severe Windstorm (DR4249) Severe Storms, Straight-line Winds, Flooding,
Landslides, and Mudslides
February 2016 Severe Windstorm (DR4253) Severe Winter Storm, Straight-Line Winds,
Flooding, Landslides, Mudslides, and a Tornado
Climate Change
Warming temperatures imply more rain over snow events reducing the snowpack and creating a
change in the character of the Olympics water storage. There will be more heavy rainfall events during the winter with commensurate opportunities for flooding and mudslides.
Table WS-2 – Precipitations: Trends and Extremes12
Source: NOPRCD Report
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Conclusion
Jefferson County is at high risk for wind storms and coastal flooding, but not recognized as being at high
risk for winter storms, as defined by the weather services. Severe local storms are probably the most common widespread hazard. They affect the entire county area when they occur. These types of storms can quickly overwhelm county resources. Citizens should be prepared for these storms; family plans should be developed, disaster kits should be assembled, and every family member should be taught how to shut off utilities to prevent damage from abrupt resumption and to prevent damage from freezing and breaking pipes. Initiating early dismissal from schools and businesses is an effective mitigation measure and should be encouraged. Local jurisdiction plans should provide a priority for road and street clearance, provision of emergency services, mutual aid with other public entities, and procedures for requesting state and federal aid if needed.
The public should be given information on emergency preparedness and self-help to prepare for better response during severe storms.
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References – WINTER STORM
1. “Severe Local Storm”, The Hazard Identification and Risk Assessment (THIRA), Jefferson County
Department of Emergency Management, 2011, pp. 34-37.
2. “Winter Storm”, NOAA NWS Glossary, Accessed August 2016. Available at: http://w1.weather.gov/glossary/index.php?letter=w
3. “Heavy Snow”, NOAA NWS Glossary, Accessed August 2016. Available at:
http://w1.weather.gov/glossary/index.php?letter=h
4. “Severe Storm Hazard Profile”, Washington State Enhanced Hazard Mitigation Plan, Military Department, Emergency Management Division, April 2013, Tab 5.7, p. 18. Available at:
http://mil.wa.gov/uploads/pdf/HAZ-MIT-PLAN/Severe_Storm_Hazard%20profile.pdf
5. “History of Storms Affecting Jefferson County’s People and Economic Acitivity”, The Hazard Identification and Risk Assessment (THIRA), Jefferson County Department of Emergency
Management, 2011, p. 34.
6. Port Townsend An Illustrated History of Shanghaiing, Shipwrecks, Soiled Doves and Sundry Souls, Thomas W. Camfield, Ah Tom Publishing Inc., 2000, p. 435.
7. Ibid. 3.
8. Ibid. 6, 443.
9. Ibid. 4, 16.
10. Ibid.
11. Severe Winter Storms Affecting Western Washington, Ken Horvath, Derived from multiple sources, September, 2016.
12. Petersen, S., Bell, J., Miller, I., Jayne, C., Dean, K., Fougerat, M., 2015. Climate Change
Preparedness Plan for the North Olympic Peninsula. A Project of the North Olympic Peninsula
Resource Conservation & Development Council and the Washington Department of Commerce, funded by the Environmental Protection Agency. p. 18. Available: www.noprcd.org Tables - WINTER STORM
WS-1 Severe Winter Storms Affecting Western Washington WS-2 Precipitations: Trends and Extremes
Figures - WINTER STORM
WS-1 Ice dresses up Haller Fountain in Port Townsend on an unusually cold day. WS-2 Port Townsend’s Water Street in 1955. WS-3 Counties Most Vulnerable to High Winds WS-4 Counties Most Vulnerable to Winter Storms
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