Cascadia Earthquake Part 5: Roads, Energy and Water


Today is the final chapter for my anaylsis. Next week I will bring you an interview, and several podcasts of ideas we can do in the community.

Click here for Part 1: Introduction, maps and fuel

Click here for Part 2: Timelines, Japan, food and Bridges Click here for

Click here for Part 3: Coastal Communities and Critical Buildings

Click here for Part 4: Land, Sea and Air

Click here for the Oregon Resilience Report.The page numbers are the electric (vs. print out) number and not the true page numbers.

Local Roads and Streets

“In addition to local roads and streets, Oregon has thousands of miles of forest roads, and it may be possible to use these for low-volume, temporary local detours in the event of a major disaster. Many of these forest roads are privately owned and will also be subject to significant damage in a Cascadia subduction zone earthquake. Nonetheless, such local-road detours will likely serve emergency responders, repair crews, and vehicles transporting food and other critical supplies, and will therefore play an important role as recovery efforts progress and a minimum level of service is restored.” Pg156

Chart of when they would like to be up and running. Page 157

“Analysis suggests that the longer the state delays increasing its investment in bridge and slope strengthening, the greater the cost and potential adverse effects an earthquake will have on the state’s economy. If risks related to bridges and slopes are left unaddressed, the odds grow every day that we will be unprepared for an increasingly likely major earthquake.” pg162

“Several other proposed local alternative routes are included in the Local Agency Alternatives to State Highway Lifeline Routes, a supplement to this Report. These routes will be studied at a later time as possible alternatives to state highway lifeline routes.”      Pg 172


Oregon’s critical energy infrastructure hub (CEI Hub) covers a six-mile stretch on the lower Willamette River between the southern tip of Sauvie Island and the Fremont Bridge on U.S. Highway 30. This relatively small area in Portland is the site of liquid fuel, natural gas, and electrical infrastructure and facilities; it is also an area with significant seismic hazard. The energy sector facilities in the CEI Hub include:

• All of Oregon’s major liquid fuel port terminals.

• Liquid fuel transmission pipelines and transfer stations.

• Natural gas transmission pipelines.

• A liquefied natural gas storage facility.

• High voltage electric substations and transmission lines.

• Electrical substations for local distribution.

More than 90 percent of Oregon’s refined petroleum products come from the Puget Sound area of Washington State. Oregon imports the liquid fuel by pipeline and marine vessels; it passes through the CEI Hub before it is distributed throughout Oregon to the end users. (One large consumer is the Portland International Airport.) In addition, a portion of the state’s natural gas fuel supply passes through the CEI Hub; and a high voltage electrical transmission corridor both crosses the area and supplies power to it. pg180

The liquid fuel pipeline was largely constructed in the 1960s when the regional seismic hazards were unknown and state-of-practice construction techniques did not include any reference to seismic standards. The regional seismic hazards are now known to be significant, and the soils at the river crossings are known to be susceptible to liquefaction and lateral spreading. The 1960s vintage pipeline design did not consider ground movements from lateral spreading at river crossings or other earthquake-induced stresses on the pipelines that may cause damage and multiple breaks. A break in the pipe would have a significant impact on all of the petrochemical facilities in the CEI Hub and could result in a statewide fuel shortage.pg184

Natural Gas

Oregon’s largest natural gas service provider receives the majority of its natural gas from pipelines that cross under the Columbia River near St. Helens, Sauvie Island, and also between Washougal, Washington, and Troutdale, Oregon. One of the natural gas pipelines crosses under the Multnomah Channel near the gate station at the southern end of Sauvie Island. The soils at these river crossings are subject to liquefaction and lateral spreading, and the pipes are of 1960s vintage. However, natural gas pipelines constructed after the mid-1950s have been found to perform very well during significant seismic events. Oregon’s largest natural gas supplier has the strategic advantage of on-system storage (within the company’s service territory), which would allow the company to provide natural gas service to unaffected customers while any damaged natural gas pipelines supplying the area are being restored. 186

“Recent unpublished BPA Cascadia earthquake scenario studies of the existing transmission line system indicate that BPA’s main grid would require between 7 and 51 days for completion of emergency damage repairs to the transmission line system (Oregon and Washington) after a magnitude 9.0 Cascadia earthquake. This scenario assumes many ideal conditions (for example, that BPA employees and contractor resources are immediately available, all roads and bridges are passable, and sufficient fuel is available), which is optimistic.” Pg188

“Over the past 25 years, NW Natural has implemented an aggressive, enhanced pipeline safety program to replace older infrastructure that may not be as resilient to a Cascadia subduction zone event. The company completed the replacement of all cast iron pipe in 2000 and will complete the replacement of its bare steel piping infrastructure in the near future.” Pg 189

Graph when services could be online. Please take note; this is only if we focus on the problem for 50 years. Page 191

We are almost there, the end is near. Last one hundred pages to go. YEA!

Information and Communications 

“The Oregon coast would most likely experience strong ground shaking for over three minutes. Facilities within the tsunami inundation zones would be extensively damaged; in many cases, they would not be repairable. Facilities outside of the tsunami zone would be heavily damaged, disrupting current levels of service for periods measured in months. Cabling that runs through conduits supported on or in transportation bridges is likely to be damaged or severed completely when the bridges fail.” pg 193 

Water and Wastewater Systems Introduction

Oregon’s water and wastewater systems are especially vulnerable to damage resulting from a Cascadia subduction zone earthquake. Some of the inherent seismic vulnerabilities of water and wastewater systems include:

  •  The systems tend to be large and complex, consisting of a combination of pipeline networks serving large areas and concentrated facilities (such as treatment plants and pump stations), with numerous potential points of failure.
  • The systems are highly dependent on other resources—such as power, transportation, chemicals, and skilled staff—to remain operational and to complete needed repairs.
  • The systems are financially dependent on consistent revenue streams to fund ongoing operations, maintenance, and debt service obligations.
  • Essential facilities, such as intakes, treatment plants, pump stations, and outfalls, are often located near rivers and lakes and are vulnerable to damage from liquefaction of alluvial soils.
  • Many critical facilities, such as reservoirs, pump stations, and treatment plants, were designed and constructed before the adoption of seismic design standards that reflect the current state of knowledge of regional seismicity.
  • Pipeline networks include extensive use of non-ductile (inflexible) materials, such as concrete and cast-iron pipe, which tend to fail during strong ground motion.
  • Pipelines are especially vulnerable to failure from permanent ground deformation (resulting from liquefaction and landslides), because the deformation causes push-on pipe joints to separate.
  • Water and sewer pipelines tend to be prone to failure at connections to aboveground structures, such as reservoirs, treatment plants, pump stations, and service connections to homes.
  • Water from leaks and breaks in water pipelines and private plumbing systems will cause collateral damage, drain available water storage, and contribute to loss of water supply and pressure, which will in turn result in a loss of fire protection capability.
  • The performance of gravity sanitation and storm sewers depends on accurate grades and slopes, which are disrupted by ground displacement resulting from liquefaction.
  • Failures of storm sewers can contribute to localized flooding during even minor rain events, resulting in collateral damage. Page 217

There is a great statement on pg 218 and the following pages have pictures of broken pipes.

Water for Fire Suppression

In the current state of readiness, existing water systems would experience extensive leaks and breaks in water supply pipelines. These leaks, coupled with loss of water supply facilities, such as treatment plants and pump stations, would drain the water systems. This loss of volume and pressure would critically limit the availability of water supply for conventional urban firefighting: fire hydrants would be rendered useless, and many fire sprinkler systems would be inoperable (even those sprinkler systems that remain intact).  Pg221

 J:  This is a VERY powerful statement!  If the fuel is gone and the water is gone, how do we fight the fires?!?

Potable Water Supplies

  • In the current state of readiness, water utilities would be unable to provide water from the existing distribution system. Communities would rely on emergency supplies for the first one to two weeks, depending on location and on the condition of transportation infrastructure. Some areas would have no water supplies during that time. Water for healthcare facilities such as hospitals would be severely restricted. Emergency water supplies would meet only subsistence needs (for example, direct consumption and very limited bathing). For the first one to two months, water would be delivered via tankers to smaller tanks and bladders distributed throughout the community. People would wait in line to fill their containers and then carry the water home. Some water would come from portable water treatment units provided by the military, equipment suppliers, and foreign countries; however, the quantity of water supplied from those resources would be small compared to demands. Photos of water distribution following other earthquakes are presented in Figures 8.11–8.13.  pg223

 In areas where the potable water system is still functioning, wastewater would be generated and discharged into rivers, streams, and lakes. Rivers would quickly become polluted with wastewater solids, as they were prior to the advent of treatment plants in the first half of the twentieth century. Water treatment plants that draw raw water from contaminated rivers would likely become compromised or would require extraordinary measures, such as operating at very low treatment rates and high dosing rates for treatment chemicals.  Pg 227

J:  Please visit for how to take care of your waste.  DON’T USE water to flush a toilet; you will need that water to live.   

Anticipated Seismic Hazards

A number of seismic hazards other than shaking and ground motion are associated with a Cascadia subduction zone earthquake.

  • Liquefaction: Liquefaction occurs when shaking during the seismic event causes a temporary increase in ground water pressure—the result is a loss of soil bearing capacity. Liquefaction can cause structures to settle and pipe connections to shear. The probability of liquefaction occurring is medium to high in the valley as well as in portions of the coast. In the valley, areas such as those near Forest Grove, McMinnville, Albany, Woodburn, and along the Columbia River, have the highest risk of liquefaction. Along the coast, areas such as Astoria, Tillamook, Waldport, Florence, and Coos Bay have the highest risk of liquefaction.
  • Landslides: The likelihood of permanent ground deformation due to landslides is high to very high for the coast and generally low for the valley and central/eastern zones.  Pg 241

“Begin aggressive public information efforts to re-set public expectations for a realistic response time. Local governments should consider using local and state planning processes and tools to integrate seismic resilience into their community development and hazard preparation policies.”

  • The old guideline of having a 72-hour emergency survival kit falls far short of the anticipated needs given the extensive impacts of a Cascadia subduction zone earthquake. Even if basic supplies could be readily and broadly dispersed, it would likely take more than three days to achieve that dispersal, and emergency supplies would still fall short of what many people need to avoid deteriorating health (for example, medications, medical equipment, and ongoing healthcare support). There is clear value in members of the public having robust emergency supplies. In many areas, subsistence levels of food and water may be available within a week, but the public should be advised that response will take much more than 72 hours, and recovery times will likely be measured in months. This is especially important in coastal communities where response times could be measured in weeks, and recovery times could be measured in years. pg 248

This ends my anaysis of the report.  There are about 30 pages of powerslides, letter and such.  I recommend that everyone should read the full report and not rely on what I have outlined here.

I want to THANK every single person involved with this report.  All of the volunteers and the experts.  All of those in government that pushed to make this report happen.  Thank you to all of those that will take this report to champion your cause to futher strengthen Oregon’s Resiliance.  We are all in this together.

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