Volcanoes in Portland, Oregon

Located in Portland, Oregon, there lie many volcanoes. When thinking of volcanoes, Oregon doesn't come to mind right away; however, Portland, Oregon is located along the Cascade Volcanic Arc, and is home to and around 5 volcanoes: Mount St. Helens, Mount Hood, Powell Butte Nature Park, Mount Tabor, and Rocky Butte Nature Area. Personally, I have not been to Oregon or seen any of these volcanoes first hand, but I must say Oregon is a beautiful state. If I am not able to live in Oregon, I, for sure, will plan a trip to visit the breathtaking state. I am very interested in exploring the state. Portland has a very diverse population and a unique location with the wilderness and the city within a close proximity. The beautiful city is home to many gardens, museums, and parks (See Where Portland, OR, Oregon Ranks Among the Best Places to Live).

Typically, volcanoes are related to plate tectonics and have existed for a very long time. Volcanoes are located at plate boundaries where magma can be produced in the spreading and sinking of plates. There are four major types of volcanoes that vary in size, shape, and composition. The type of volcanoes that form result in the magma is formed and the four type of volcanoes are cinder cone, shield, composite, and lava domes. Volcanic domes can either be explosive or nonexplosive and the lava can get up to about 2,000 degrees Fahrenheit! Volcanoes can be very destructive and have the potential to do a deadly amount of damage (Keller, Edward A., et al.). Volcanoes can become high mountains but the next day they can erupt and destroy half of their structure. While living in Portland, it is common knowledge that Mount Hood is close to the city and could possibly become active again like Mount St. Helens (although located in southern Washington) did about thirty-eight years ago. According to Carolyn L. Driedger, spokesperson for United States Geological Survey-Cascades Volcano Observatory, Additionally, we'd soon be observing black streaks of lahars (volcanic mudflows) as they course down river valleys towards the Columbia River,' told to The Oregonian as Lizzy Acker wrote in her article, Watch: What might it look like if Mount Hood erupted today? Driedger also states that a volcanic eruption wouldn't be random nor out of the question (Acker).

As stated before, Mount St. Helens is located near Portland, in southern Washington. The region around Mount St. Helens is home to one of the best singletrack rides in the Pacific Northwest. The 16-mile out-and-back Ape Canyon Trail weaves through thick forests and eerie pumice plains alike while affording riders unmatched views of the ruinous blast zone and lava flow visitors; however, do not have to worry about an eruption as the volcano is building up pressure and not likely to erupt soon (Wastradowski, Matt, et al.). Mount St. Helen's is considered dormant not extinct which means the magma can no longer reach the volcano (Volcano World). Mount Hood is the tallest peak in Oregon at 11,000 feet above sea level which houses many beautiful tourist attraction parks but is considered a very high threat volcano because of the regularly recorded earthquakes by the U.S. Geological Survey from 2005. The volcano in which Powell Butte Nature Park resides on is, not to worry, extinct and displays many amazing views. Mount Tabor, an extinct volcanic cinder cone, is considered a city's natural crown jewels and houses some of the best hiking paths for hikers and cyclists. Although Rocky Butte Natural Area is the best looking, exploring the area will lead to high quality hiking paths and the best views while maybe enjoying a picnic after the trek to the top. The extinct volcanoes have not been recorded of erupting and will not erupt again (Wastradowski, Matt, et al.).

The probability of one of these five volcanoes erupting anytime soon is very unlikely. Most of them are extinct; however, some are dormant. Mount Hood is the most likely as there have been two past recorded eruptions identified by the USGS. The first one occurred about 100,000 years ago that took out the Hood River valley as a lahar was formed and continued to surge up the White Salmon River valley. The second one was only about 1,500 years ago and not nearly as destructive. In the second eruption, the lahar that formed was carrying eight feet boulders. It is possibility of Mount Hood erupting again and if it did, USGS thinks that it will mimic these past eruptions and although the lahar might not hit Portland, the ash and dust most certainly will (Mclendon). An increasing number of earthquakes can lead to volcanic activity as the earthquakes helps move the magma towards the surface. Scientists from the Geophysics Program at the University of Washington and the USGS have been monitoring the earthquakes occurring at Mount Hood and the scientists are looking for signs of increased earthquake activity or a measurement of the depths of the earthquakes to become shallower which may lead to changes in gases or the shape of the volcano's flanks. Although scientists are able to provide some sort of warning to the public, the cannot exactly identify when the eruption will possible begin. If Mount Hood does erupt, there will be many questions that will need to be addressed (Diggles, Volcano World).

If Mount Hood does erupt, it will not be explosive but instead it will include lava flows that may travel more than 8 miles from the source which can also pile up forming a lava dome. These lava flows can get significantly hot melting a good amount of ice that lead to the creation of lahars, which can also be created by quick erosion of loose rock or gravel during very heavy rains, that have predominated the eruptive activity of Mount Hood. It is predicted that the entire next eruption will be smaller or similar size to the one from 1,500 years ago (Diggles). In the 1980 eruption of Mount St. Helens, The Washington Department of Game estimated that 11,000 hares, 6,000 deer, 5,200 elk, 1,400 coyotes, 300 bobcats, 200 black bears, and 15 mountain lions died from the pyroclastic flows. The eruption can cause an increase in acidity and temperature which can lead to damaging and killing the aquatic animals and will also impact birds and insects (Volcano World). There are many different hazards and hazard zones that are connected to Mount Hood that may be affected in the event of a volcanic eruption. The proximal hazard zone extends 15 miles and can include avalanches and landslides and the lahar hazard zones can travel longer distances which can reach as far as 62 miles. Areas that are within the proximal hazard zone should be warned and already evacuated before the eruption begins. Distal hazard zones include areas that are pathways for lahars and the travel time is not nearly as fast as a lahar in the proximal hazard zone, and gives residents or visitors more time to reach safety. The water may be affected as the pipes cross the distal hazard zone adjacent to the Sandy River. The zones are divided into smaller zones based on the vent location. In a past eruption, the vent was within a close distance of Crater Rock, now a trail within Mount Hood National Park. It is predicted that location of the vent for the future eruption will be within the same area. By using the map and legend from the previous page, you can see that areas within the PA and DA zones will be affected more. Towns and cities located east of the volcano are more likely to get the most damage and will probably experience large amounts of tephra thick enough to cause a roof to collapse. Large, deep-seated landslides, debris flow deposits, and zones of steep slopes are the three types of landslide hazards that may be shown. The effects and hazards of earthquakes are very important in relation to volcanoes because both hazards are linked to one another. The shaking of an earthquake is closely monitored to help in the ability to forecast and warn others of volcanic activity (Diggles, Oregon Department of Geology). The hazard zones on the map from the picture on the previous page were figured out in relation with the distance from the volcano, type of hazardous events, and location of the vent (Diggles).

The figures below show the formation of a lahar and the hazards of a lahar from the eruption of Mount St. Helens from March 19, 1992.

It is important for the Oregonians to count on each other within the community and homes. The Oregon's Office of Emergency Management recommends people to be prepared to be on their own for a minimum of two weeks. Preparing or at least preparing the best you can two weeks prior, will help emergency responders in the long term so make the most of their resources. Building kits is recommended; however, each families' kit will be different (2 Weeks Ready). Structures with the greatest risk of being impacted by a volcanic eruption are ones that are close to the river. The degree of hazard decreases as height above a channel increases, but large lahars can affect areas more than 30 vertical meters (100 vertical feet) above river beds. States, national parks, and forests, are factors of the environment that also will be affected. Depending on the type and magnitude of the ashfall, small mountain communities will receive a thickness of about 1.5 centimeters. Dams, reservoirs, energy generating facilities, and highways located within the mountain communities will be affected also. Although volcanoes are considered the lowest rank hazard in the county, it is still important to plan for the hazard (Hood River County Multi-Jurisdictional Natural Hazards Mitigation Plan). The communities set up emergency plans and it is important to follow those instructions and as the eruption develops, officials will make sure to update the hazard zones (Volcanoes). I think that the Portland community does have a good plan in place with the 2 Weeks Ready page and the accessible 2 Weeks Ready Facebook page. and the amount of notifications you will get if an eruption does occur. The citizens will get notified right away in case of a volcanic eruption. The notifications from officials definitely helps in assisting all of the residents and visitors to safety.

One way to better address the hazard would be to advertise volcano safety pamphlets around the city to inform everyone. I also think, the city should make their emergency plan easier to access on the computer. There should be plans posted on all buildings in case of emergency. The city should focus on becoming more technological. I think this will help because our generation is based on technology. Portland needs to start now, or soon they will be behind.

Although I have never encountered a volcanic eruption, and I hope I do not have to, I have learned how to prepare myself and what to expect if I were in the event of a volcanic eruption in Portland, Oregon. What would happen if I did encounter an eruption? Would I escape quick enough? I believe that if I were to encounter a volcanic eruption, I would be fully prepared and I would be able to help others around me. Portland is not at as high of a risk of an eruption as Hawaii, but it is still important to know how to address the situation and recover from this hazard. With the accessible information on the Oregon websites and the preparation Facebook pages and articles, the citizens will still question what to do in case of an eruption. I am excited to spread my knowledge about volcanoes and hopefully when I visit Portland, Mount Hood does not erupt.

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