Hazard Assessment for Memphis, Tennessee Environmental Geology April 24, 2012

Hazard Assessment for Memphis, Tennessee A natural disaster is defined as any event or force of nature that has catastrophic consequences (“natural disaster”). The only reason that these events are considered to have catastrophic consequences is because people are negatively affected by these natural events. If people were not present during these events, they would not be considered catastrophic. The more people affected means the event would be considered more catastrophic. Tennessee is the 17th most populated state, with approximately 6.4 million residents (Infoplease.com). Within the state, Shelby county covers the most area, (755 square miles), and is also the most populated county, with approximately 927,644 people residing there (Infoplease.com). Shelby county includes the city of Memphis. Memphis is the most populated city within Tennessee with at least 645,000 residents (Infoplease.com). I have attached several maps in order to see different parts of the land. Map I shows where the county lines are located within Tennessee. You can also see where Memphis is located within the county. Map II shows the elevation levels of the state. As you can see in that map, Memphis is located within the lowest elevation levels of the state. Map III shows the rivers that run throughout the state. The main river that runs between the Tennessee, Arkansas, and Missouri borders is the Mississippi River. There are several natural disasters that I would consider to be threats to the Memphis area. One natural disaster that I would consider to be a concern to Memphis would be an earthquake. According to the United States Geological Survey, (USGS), there is an approximately six percent chance that there will be a major earthquake within 50 kilometers of

Memphis in the next 50 years (Homefacts.com). The last earthquakes that had magnitudes of five were in 1976 and 1991 (Homefacts.com). The earthquake recorded in 1976 was approximately 40 miles away from Memphis. Looking at the sources found, I see that Tennessee has had its fair share of earthquakes, so I would say that another earthquake occurring in the area should be a concern of the citizens and government officials. “There is a broad agreement in the scientific community that a continuing concern exists for a major destructive earthquake in the New Madrid seismic zone. Many structures in Memphis, Tenn.…and other communities in the central Mississippi River Valley region are vulnerable and at risk for severe ground shaking.” (USGS.gov). The New Madrid Earthquake of 1812 was one of the most significant events in U.S. history. Topographic changes were noted over an area of 75,000 to 130,000 square kilometers, with the total area shaken being at least five million square kilometers (USGS.gov). Back then, the damage was minimal because of sparse population. Nowadays, an earthquake that severe could result in “great loss of life and property damage in the billions of dollars” (Cusec.org). The fact that Memphis is the most populated city in the state, a small earthquake could cause a significant amount of damage. “By learning about the potential earthquake hazards in your area and by taking certain preparedness measures now, you can increase your chances of surviving an earthquake and minimize its dangerous and damaging impacts” (Cusec.org). There are many organizations that Memphis has in order to help citizens learn how to prepare for these catastrophic events, and what to do in order to survive. One organization is the Radio Amateur Civil Emergency Service (R.A.C.E.S.), which is a volunteer communications group that assists the Shelby county area.

R.A.C.E.S. provides emergency personnel that can help with communications during local, regional, or national emergency/disaster events (Cityofmemphis.org). Another organization that provides help during emergency situations is the Memphis/Shelby County Emergency Management Agency (EMA). The EMA helps local, state, and federal agencies with response to disasters that requires a multi-agency/multi-jurisdictional response. The EMA has satellite links with the National Weather Service that activates sirens in order to warn the residents of multiple cities, including Memphis (Cityofmemphis.org). There are also things that the citizens and homeowners could do in order to minimize the damage during earthquake. Earthquake drills are a great way to help enforce the importance of preparedness, and to prevent panic and injury during an earthquake. Families should have emergency plans that lay out where everyone is going to be and where to reunite with one another. Keep a flashlight and a batterypowered radio in the home. Place large or heavy objects on lower shelves, and fasten the shelves to walls. And lastly, have a seven to ten day supply of food and water (Cusec.org). You can never be too prepared for any natural disaster, so being safe is better than being sorry. Not all natural disasters are threats to Memphis. Volcanoes are an example of a natural disaster that is not a threat to the Memphis area. There are no known volcanoes in the area that would cause any kind of harm to the residents of Memphis. Historically, there have not been any known volcanoes in the area either. Memphis is not located on any fault boundaries, so I would think that there would no volcanoes forming in the area any time in the near future. Hurricanes are a little more of a concern for Memphis. The western area of the state has the possibility of being affected by the end of certain storms. Hurricane Katrina is an example of

this situation in which Memphis can be affected by storms not necessarily in the direct area. When Hurricane Katrina hit the U.S. in 2005, multiple counties in Tennessee were evacuated; Shelby County was one of those counties (Fema.gov). I would consider Memphis to be slightly concern about hurricanes occurring in the area, especially since the city is located at a low elevation. The lower elevation would be more susceptible to flooding. The government should have adequate warning of the hurricane, since it would most likely be coming from the Gulf of Mexico. I would also expect that the citizens would be prepared for hurricanes, since they are used to flooding situations. Tornadoes, I feel, are more of a concern than hurricanes. There are many more tornadoes in the middle of the state then there are on the outskirts. Tornadoes are more likely to strike open plains rather than in an urban area, like Memphis. “The reality is, very few tornadoes ever touch down in the city of Memphis….. Nevertheless, tornadoes can and have struck within the city” (About.com). There have been numerous tornadoes that have affected Shelby county, but not nearly as many as the middle of the state. The last one that affected Shelby County, and had a high death count was in 1987, with at least 120 deaths (NWS Memphis
Forecast Area Tornado Database). There have since been tornadoes that have caused deaths,

which is not surprising considering the amount of people that live in the city. With all the tornadoes that have gone through the county, there has always been a significant amount of damage. That also is understandable since there are a lot of buildings in the city. There have also been plenty of tornado warnings for the state, but not all of them affecting Shelby County. The last tornado warning that included Shelby County was on May 9, 2011.

In order to be prepared for a tornado, there are several things we could do. First of all, avoid windows and seek shelter in the center-most room on the lowest floor possible. Use your hands and arms to protect yourself from falling debris. Also, keep some sort of identification on you at all times in case you are hurt or disoriented (About.com). Keeping identification on you is a good idea for every natural disaster. It will help emergency personnel identify who you are and hopefully get you back with your family. Tsunamis are another type of natural disaster that is not a concern for Memphis. There have been no known tsunamis recorded for Memphis. I do not think that there will be any future tsunamis in Memphis because there is no ocean or large body of water located near Memphis. The Mississippi River is near Memphis, but the river does not create waves that would be large enough to create a seismic wave. Even though tsunamis are not a threat to the city, flooding is a huge concern for the city. The Mississippi River is right near the city, so that would be a reason as to why the area floods frequently. The city is also at a low elevation, which is another reason as to why the area floods frequently. There is currently an active flood warning in effective right now (Fema.gov). Last year, there was flood that occurred in the beginning of May. The Mississippi River was supposed to rise to a record level of 48 feet, with 48.7 being the record crest in 1937. More than 1,300 homes were ordered to evacuate and nearly 400 people were living in shelters. According to an article on abcnews.com, the most extensive damage occurred in Memphis, where “entire neighborhoods have been swallowed by the water and vehicles completely submerged” (Tanglao, “Memphis Flooding”). Since this obviously happens frequently, the

citizens and government have ideas of what the levees can hold, and what the river’s maximum water level is. To prepare for flooding situations, there are certain things the government should tell their residents in order to make sure they are safe. They must send out warnings letting people know when and if the water level is high enough to go over the lands limits. In Memphis, the government should be able to accurately know when and if the Mississippi River has reached its maximum, and if people should evacuate their homes. As a resident, you should also be aware of what is going on in your community and know about the town’s emergency plans. You should also have sump pumps with back-up power in order to prevent contamination of the flooded water. Turn off all utilities at the main power switch in order to prevent electrocution. Fill bathtubs, sinks, and soda bottles with clean water, so you have water to drink that is not contaminated. You should also have water bottles and a food supply that will last a couple of days (Bt.cdc.gov). On the opposite end of the spectrum, wildfires are another example of a non-threat to Memphis. There are no forests in Memphis because it is a highly urban area with lots of people and buildings. The last wildfire reported in Memphis was in 1952, when there was a serious drought (Tnema.org). Even though there was that wildfire many years ago, I do not think that there is a serious threat to Memphis for another wildfire. Lastly, I also think that there is not a threat for extreme winter conditions to occur in Memphis. The last warning for some sort of winter conditions for Shelby County was in February 1992 (Fema.gov). Even though that was not too long ago, I still feel like there is not a

huge concern for extreme winter conditions to occur any time soon again. Since Memphis is further south, they do not really get harsh winters like we do here in Pennsylvania. Memphis Tennessee has its fair share of natural disasters. They have to be concerned about earthquakes, floods, and tornadoes the most, while extreme winter conditions, volcanoes, and tsunamis the least concerned about. Every place on the Earth has to be concerned with natural disasters. Humans make the disasters a lot worse than they actually are, but there is nobody else to blame but ourselves. We get in the way of nature, and have to pay the consequences some way or another.

Map I

Map II

Map III

Works Cited Centers for Disease Control and Prevention. Natural Disasters & Severe Weather. Web. 12 April 2012. Central United States Earthquake Consortium. Earthquake Safety. Web. 12 April 2012. City of Memphis. Emergency Management Agency. 2003-2011. Web. 12 April 2012. Federal Emergency Management Agency. Tennessee Disaster History. 26 March 2012. Web. 12 April 2012. “Memphis Earthquake Information.” Homefacts.com. 2012. Web. 12 April 2012. “Natural Disaster.” Dictionary.com. Web. NWS Memphis Forecast Area Tornado Database. Web. 12 April 2012. Tanglao, Leezel. “Memphis Flooding: Mississippi River Nears Record Highs.” AbcNews.com. 9 May 2011. Web. 12 April 2012. “Tennessee.” Information Please Database. Pearson Education, 2011. Web. 12 April 2012. Tennessee Emergency Management Agency. Wildfire. Web. 12 April 2012. “Tornadoes in Memphis: What to expect and how to stay safe.” About.com. The New York Times Company, 4 April 2011. Web. 12 April 2012. United States Geological Survey. Earthquake Hazard in the New Madrid Seismic Zone Remains a Concern. 3 August 2009. Web. 12 April 2012.

United States Geological Survey. Tennessee: Earthquake History. 21 October 2009. Web. 12 April 2012.