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Chapter 7. METHODOLOGIES FOR CHARACTERIZINGNG HURRICANE PREPAREDNESS AND RECOVERY ALTERNATIVES

Introduction

For the Hampton Roads District of the Virginia Department of Transportation, the enhancement of road systems can increase its robustness, redundancy and or resilience in a hurricane. Chapter 7, Methodologies for characterizing hurricane preparedness and recovery alternatives, describes the cost, risk and benefit tradeoff analysis of enhancement alternatives. The goal of the chapter is to develop case studies for road systems, in addition to signs, lights and signals, as well as build a framework that aids VDOT in evaluating enhancement alternatives based on the enhancement costs and the potential losses from hurricanes. The organization of chapter 7 is as follows ??The purpose and scope of chapter 7. ??A description of all the different attributes in the case studies including explanations on

how one can improve the redundancy, resilience, and robustness of different road systems.

??A template worksheet explaining how to develop more alternatives and how to import them into its own case study based on other road systems.

??A case study that expands on roads, signals, and lights looking at improving the robustness, resilience, and redundancy of each system.

??A case study that looks at mitigating flood damage taking a look at damage done by heavy rainfall and from storm surge. Some of the road systems in the case study include protecting roadways and tunnels from flooding.

??A case study that looks at enhancing the road, bridge, and tunnel network throughout the Hampton Roads District.

??A case study that looks at enhancing the smart highway systems throughout the area and includes taking a look at different alternatives in protecting the cameras, radar systems, motion detectors, and variable message signs that make up the smart highway system.

??The final section contains suggestions and recommendations for further work.

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Purpose and Scope

After a hurricane hits the Hampton Roads district, the road systems in the area are in complete disorder leaving some communities stranded sometimes. The purpose of the current effort is to aid the Virginia Department of Transportation (VDOT) with its preparations before a hurricane and its recovery efforts after a hurricane. To help VDOT prepare better in assessing the risks, costs and benefits, case studies will be examined to see how road systems can be enhanced through the attributes of redundancy, robustness, and resilience. In the end, a tool has been developed to aid VDOT in evaluating the alternatives in all of the case studies. The tool is accessible on the Internet at the site: http://www.virginia.edu/~risk, so that VDOT has constant access to them into the future.

Methods and Materials Introduction to the Case Studies The following section describes the traffic systems considered in throughout the chapter and characterizes the methods for enhancing them. Further details of the case studies are contained in the appendices. In the case studies, thirty-four different classes of alternatives were identified and analyzed. Each alternative looks at trying to improve the resilience, robustness, and redundancy of different road systems. Improving the resilience in the system trying to help return the system back to normal with minimal replacement of materials or upgrading of systems. It attempts to have the system to “bounce back” faster immediately after the hurricane. Improving the robustness of a system tries to upgrade the system so that it makes it stronger and last up against stronger hurricanes. It might seek to improve the maximum wind velocity or the higher storm surge it can handle. Third, there is improving the redundancy of the system which adds the number of equipment in a certain area so that if one piece of the system fails, there are plenty more that are around that can still do the job. Furthermore, each alternative is looked at to show whether it is most associated with pre-events (before the hurricane) or post-events (after the hurricane). The pre-event and post-event phases are broken further into short, medium, and long term. Short-term events are the hours to days before the hurricane hit. Medium-term is weeks to months or basically, during the hurricane season. Long-term is the preparation years in advance or basically general advancements in the building of the systems to be better prepared. The same time periods apply for post-events except they address the aftermath of the hurricane. In addition to the periods, the case studies characterize the impacts of each alternative and whether it aids in evacuation and repopulation of the area. The impacts of each alternative are based on the Virginia Department of Transportation’s goals of protecting life, property, and the environment. The impacts that the case studies consider include cost, recovery time saved, human lives and the safety of the public, economic impact to the community, property saved, and protection of the environment. The case study looks at how each alternative protect against

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stronger winds, prevent against higher storm surges, or handle greater traffic. The last part of the case study characterizes whether or not each alternative helps in the aid to evacuate or repopulate the area. Template of a Case Study Table 7.1 shows the template of a case study worksheet. The analyst enters filled circles where each area has an impact on the alternative. If the alternative enhances the system through robustness, then robustness would receive a filled circle. Likewise, if alternative 1 saves VDOT time and cost, then filled circles would be placed in the respective columns as well. If there is only a minor impact, for example, in the area of economic impact, then a half- filled circle is used. Finally, depending on whether the alternative would be receptive to wind damage, storm surge damage, or say another destructive force, then that would be replaced in that column. The framework is applicable to a wide range of alternatives and disaster scenarios.

Road System: List road system here

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1. List alternative 1 here

Results Signs, Signals, and Lights One of the major concerns whenever a hurricane approaches is the wind damage and the systems affected from strong winds. One of the larger systems affected by wind damage are all of the signs, signals, and lights throughout the area. When the wind knocks these out along with all of the trees or landmarks in particular areas, people will not recognize their old neighborhoods. They need signs, signals, and lights to guide them through their neighborhood and the faster recovery of these systems, the quicker the area will return to normal. The following classes of alternatives look at how lights, signals, and signs can be enhanced throughout the Hampton Roads District of Virginia. The following case study is an extension from the previous one done a few years ago from the previous Capstone groups.

Table 7.1 Template of the framework for characterizing enhancement alternatives

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Signs Enhancing signs usually requires new designs for posts and structures. There are two major factors related to the wind load a sign is capable of withstanding. One is the size of the sign panel; the other is the design of the structural support for the sign. In order to increase the maximum wind speeds that shoulder-mounted signs can withstand by 20 miles per hour, VDOT needs to increase the size of the footing, the number of bolts, and the size of steel for a 30 to 40% greater structural resistance capacity (Lambert et al. 1999). Enhancing the signs increases the robustness of the system but not the resilience and redundancy of the system. Another way to enhance the system is to store more signs in the warehouse so that VDOT can improve the redundancy of the system because VDOT will not have as many signs to put back up after the storm is over. A third way to enhance signs is to make them detachable, thus increasing the resilience in the system but not the redundancy and the robustness of the system because it will improve the time greatly it takes to recover and bounce back from a hurricane. All of these methods improve the time saved in recovery, however, not all have a cost savings mainly because man hours of preparation time may offset the time it would take to clean up the signs destroyed in the hurricane. Table 7.2 shows the case study performed for the various ways to help enhance signs.

Table 7.2 A case study characterizing the enhancement of roadway signs. A filled circle represents a major impact while a half- filled circle represents a minor impact.

Signals A common type of signal is located at a cross intersection where a two-lane road intersects another two-lane road. The signal has two poles on either side of the street and two arms. There are three signal heads, or fixtures, on each arm. The fixtures are supported by back-straps, but only the middle fixture is strapped. A less costly way to upgrade a signal system as opposed to completely redesigning and replacing it is to upgrade the strength of the bolts, work on the bottom support structure, and increase the strapping of fixtures to arms (Lambert et al. 1999). The enhancement of signals increases the robustness of the system but not the resilience and redundancy of the system. A way to enhance the redundancy of the system is to store more

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signals in the warehouse because VDOT will have signals already made to put back up after the storm is over. A third way to enhance signals is to make them detachable, increasing the resilience in the system but not the redundancy and the robustness of the system because it will improve the time greatly it takes to recover and bounce back from a hurricane. All of these methods improve the time saved in recovery, however, not all have a cost savings mainly because man hours of preparation time may offset the time it would take to clean up the signals destroyed in the hurricane. Table 7.3 shows the case study performed for the various ways to enhance signs. Table 7.3 A case study characterizing the enhancement of signals. A filled circle represents a major impact while a half- filled circle represents a minor impact.

Lights Two major types of lights are 1) a roadway light, which has a pole and an arm extending above the road, and 2) a high mast light, which has a 100-foot pole and multiple lights on the top of the pole and illuminates highway interchanges. Enhancing lights requires making stronger poles either by using stronger materials or making them bigger. Enhancing may also entail stronger and deeper foundations, especially for high mast lights to increase the robustness of the system but not the resilience and redundancy of the system. A way to enhance the redundancy of the system is to store more lights and poles in the warehouse because VDOT engineers will have lights and poles ready to be put back up after the storm is over. The final way to enhance lights is to make them detachable to increase the resilience in the system but not the redundancy and the robustness of the system because it will improve the time greatly it takes to recover and bounce back from a hurricane. The alternatives mentioned all improve the time saved in recovery, however, not all have a cost savings mainly because man hours of preparation time may offset the time it would take to clean up the lights destroyed in the hurricane. Table 7.4 summarizes the case study performed for the various ways to help enhance signs.

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Table 7.4 A case study characterizing the enhancement of signals. A filled circle represents a major impact while a half- filled circle represents a minor impact.

Flood Mitigation One of the major concerns whenever a hurricane approaches an area is flooding. There are two main ways that flooding can be caused by a hurricane. They are storm surge and heavy rainfall. Both affect large areas at a time and can lead to almost immediate damage and problems as flooding can cut off evacuation routes as well as flood key buildings throughout the area. By trying to prevent flooding in some of these key areas, one can try and minimize the amount of problems that can arise by flooding. Storm Surge Storm surge is created by a combination of low pressure and high wind speeds. Hence, the stronger the hurricane, the higher the storm surge, due to higher winds and lower pressure. Table 7.5 shows the amount of storm surge created by each category of hurricane. Trying to minimize the amount of damage caused by storm surge can be done several ways. These ways enhance the resilience and the robustness of the system. One method is to add flood gates to all of the tunnel entrances. More ways to mitigate flooding are to raise the level of the ground where bridges start, add more pumps, or increase the pump capacity so more water can be pumped out per minute. More ways one could mitigate flooding is to have sandbags ready at the entrances to the tunnels to prevent water from entering or at least to minimize it. Finally, building another tunnel can add redundancy too. The alternatives listed can either enhance the resilience, robustness, and redundancy to help mitigate flooding caused b storm surge.

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Heavy Rainfall Heavy rainfall is always associated by hurricanes. Since hurricanes are tropical by nature and have high amounts of moisture associated with them. The moisture in the hurricane falls to the ground as rain and cover large amounts of areas throughout the hurricane and can drop large amounts of rain. Rain then accumulates over and over in the same places and can lead to large flooding in flood-prone areas. Some of the most flood-prone areas is the land or roadways leading up to bridges and tunnels. To help prevent flooding in these areas, one could raise the elevation of the road, however, it is very costly. One could also put sandbags around the road, proving to be very time consuming when people do not really have time to do such a feat right before the hurricane. Finally, another way would be to try and just recover faster by having extra road clean-up crews and trucks ready to immediately clean up the debris. Table 7.6 lists a number of ways to enhance different systems to mitigate flood damage and storm surge.

Table 7.6 A case study characterizing the enhancement of systems to mitigate flooding. A filledcircle represents a major impact while a half- filled circle represents a slight impact.

Category Winds (mph) Storm Surge (feet) Damage1 74-95 4-5 Minimal2 96-110 6-8 Moderate3 111-130 9-12 Extensive4 131-155 13-18 Extreme5 >155 >18 Catastrophic

Table 7.5 Categories of Hurricanes showing the respective amount of damage depending on the strength of the hurricane.

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Roads, Bridges, and Tunnels There are various ways to enhance the roads, bridges, and tunnels throughout the Tidewater area in preparation for hurricanes. Some may be more cost effective than others, while some may be a lot more time consuming than others. To find the best alternatives to prepare for hurricanes with the funds and time available is the key to success for better evacuations. Evacuation routes may be a difference in lives saved or at the least, injuries avoided which is the number one priority at the Virginia Department of Transportation and the Department of Emergency Management. There are four main areas in how to prepare better and enhance the different road networks, tunnels, and bridges. These four areas concentrate on improving the tunnels, improving the bridges, improving the roads, and also faster recovery with preparation supplies. Tunnels Enhancing tunnels can be accomplished in at least two ways. These two ways look at increasing the robustness and redundancy of the tunnel, but not the resilience. One way to increase robustness is by strengthening the tunnel to handle more forces, a very time consuming process. By strengthening the tunnel to handle more force, one will not have to repair it if a strong hurricane with a very high storm surge came through the area. Moreover, higher storm surges can cause heavy damage to tunnels that are not located under the ground but rather just underwater because of the enormous force of the waves under the water and with the water level rising, more of the tunnel is exposed to the force and with more water in the area, the greater the force as well pushing down on the tunnel. A second way to enhance the tunnel system is by increasing the redundancy of the system, accomplished by building more tunnels. By increasing the redundancy of the system, if one tunnel is damaged, there are still plenty of other tunnels for the community to use while the other tunnel is repaired. However, doing so will yield a very high cost to build more tunnels. Tunnels have a great importance in evacuation because it helps all of the people in the Hampton Roads district evacuate and reach higher ground. Bridges Enhancing bridges can be accomplished in at least two different ways. These two ways look at increasing the robustness and redundancy of the bridge. One way to increase robustness is by strengthening the bridge to handle more forces, a very time consuming process. By strengthening the bridge to handle more force, one will not have to repair it if a strong hurricane with a very high storm surge came through the area. Moreover, higher storm surges can cause heavy damage to bridges because of the enormous force of the waves under the water and with the water level rising, more of the bridge is exposed to the force. A second way to enhance the bridge system is by increasing the redundancy of the system, accomplished by building more bridges. By increasing the redundancy of the system, if one bridge is damaged, there are still plenty of other bridges for the community to use why the other bridge is repaired. Again, choosing to build more bridges is a very costly alternative. Bridges have great importance in evacuation as well because they help get everyone away from the Hampton Roads District and onto higher ground away from shore.

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Roadways Enhancing the roads can be accomplished in two ways. These two ways look at increasing the robustness and redundancy of the roads. One way to increase robustness is by strengthening the roads to handle more traffic and can be done in at least two ways. One is by layering the roads more, or by adding a greater surface to last longer or to start coming up with better and stronger materials to build roads with. By strengthening the roads to handle more force, one will not have to maintain the roads as much if a strong hurricane caused a major evacuation of the area causing increased traffic and pressure on the roads. The second way to enhance the roads is by increasing the redundancy of the system, accomplished by either adding more lanes to the highways or just building more routes out of the Tidewater area. By increasing the redundancy of the system, if one lane is damaged, there are still plenty of other lanes for drivers to use while that other lane is repaired. Roads have great importance in evacuation as well because they help get everyone away from the Hampton Roads District and onto higher ground away from shore. Table 7.7 lists a number of ways to enhance the different systems to enhance the roads, bridges, and tunnels found in the Hampton Roads district.

Table 7.7 A case study characterizing the enhancement of roads, tunnels, and bridges. A filled circle represents a major impact while a half- filled circle represents a minor impact.

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Resilience Enhancing A third way to improve the road network is by enhancing the resilience of the system by having better preparation and recovery efforts. Some of the ways found to improve resilience are adding more VDOT trucks to the road. More trucks can get out there to clear off debris off of the highways and get traffic moving again and will also help track other problems that need attention in the area because there will be less area that each truck will have to monitor. Another way to enhance resilience is by keeping extra gravel on hand for all the potholes that get created as a result of evacuation and the returning of traffic. Because hurricanes hit large scale areas, gravel will be at a premium at the time right after a hurricane. Final, keep extra road repair kits and vehicles will be important too to help adjust lane closings and inform traffic of different traffic patterns. All of the alternatives with the exception of the repair kits themselves are important to evacuation too and all improve the resilience of the roadway systems but not the robustness or too and all improve the resilience of the roadway systems but not the robustness or redundancy of the system. Table 7.7 also lists the ways to enhance the resilience to the road systems found in the Hampton Roads district.

Smart Highway Systems

There are many different structures in smart highway systems, including: 1) Cameras, to look for traffic problems, 2) Traffic alert signs, which notify travelers of upcoming road problems, and 3) Motion detectors / Radar, which also is used to monitor traffic flows and patterns. These smart highway systems are located on tops of overpasses and help VDOT monitor traffic problems on the highways. These systems can be enhanced by preparing spares, strengthening each one to last through stronger winds, and also by adding more of them in particular areas. Motion Detectors / Radar Motion detectors and radar systems are set up throughout the Tidewater region. They are used to monitor traffic flow on the highways and interstates. Motion detectors and radar are placed in many different ways. Most of them are placed on overpasses, but some are also placed near traffic alert signs and other places where traffic flow needs to be monitored along the highway. Motion detectors and radar systems can be enhanced through the attributes of robustness, redundancy, and resilience. Strengthening motion detectors and radar systems to handle higher wind velocities enhances robustness and carrying extra inventory so they can be easily replaced when destroyed in a storm enhances redundancy. Finally, if engineers make the motion detectors and radar systems detachable, one can improve the resilience in the system so it can bounce back to normal a lot quicker too. The only grade that will be used to test cameras is wind speed as the only main way cameras are destroyed is through wind damage. Table 7.8 shows the case study performed for the various ways to help enhance motion detectors and radar systems.

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Table 7.8 A case study characterizing the enhancement of radar and motion detectors. A filled circle represents a major impact while a half- filled circle represents a minor impact.

Cameras Cameras are mainly placed periodically on tops of overpasses and highway signs that overlook the interstates throughout the Tidewater region. Cameras show pictures of the traffic on the interstates to help give officials warning signs of possible accidents or other highway problems. Cameras can be enhanced through the attributes of robustness, redundancy, and resilience. Strengthening the cameras to handle higher wind velocities enhances robustness and carrying extra inventory so they can be easily replaced when destroyed in a storm enhances redundancy. Finally, by making the cameras detachable, one can improve the resilience in the system so it can bounce back to normal a lot quicker too. The only grade that will be used to test cameras is wind speed as the only main way cameras are destroyed is through wind damage. Table 7.9 shows the case study performed for the various ways to help enhance cameras.

Table 7.9 A case study characterizing the enhancement of cameras. A filled circle represents a major impact while a half- filled circle represents a minor impact.

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Variable Message Signs Variable message signs (VMS) are the huge signs that hang on the poles over top of the highway that alert drivers of upcoming problems on the roadway. These signs display messages of either upcoming construction, changing weather conditions, upcoming accidents, and traffic jams. Variable message signs can be enhanced through the attribute of robustness and is accomplished by strengthening the VMS to handle higher wind velocities. VDOT can also increase the redundancy by keeping extras in storage for the VMS signs destroyed in hurricanes or just put more up along the highway so if 1 or 2 do get ripped down, there are still more of them up there. However, increasing the resilience of a VMS is hard to do due to the great size of the VMS over the roadway. Because the variable message signs hang over the roadway in the air, wind speed is the only test that will be used in the analysis. Table 7.10 shows the case study performed for the various ways to help enhance variable message signs.

Table 7.10 A case study characterizing the enhancement of variable message signs. A filled circle represents a major impact while a half- filled circle represents a minor impact.

Conclusions and Recommendations The conclusions and recommendations of this effort are the following:

?? Consider a systematic approach to cost-benefit analysis for recovery and preparedness ?? Identify the variety of alternatives for redundancy, robustness, and resilience ?? Redundancy alternatives consist of keeping spares on hand, laying additional roads,

bridges, tunnels, etc. ?? Resilience alternatives consist of helping the system bounce back faster than it would

have if nothing were to be done, such as adding stronger flood gates to tunnels, sandbagging entrances at the last moment, or using detachable equipment so it is easier to take costly equipment down and put it back up.

?? Robustness alternatives consist of upgrading the equipment to last in stronger winds, last in stronger or higher storm surges, or handle heavier volumes of evacuation traffic.

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?? Look at the variety of possible alternatives ?? Determine what kind of impacts each alternative makes, including cost, time savings,

human life, economic, environment, and property ?? Decide in what time frame the alternative takes place (short, medium, long-term; pre-

event, post-event). ?? Decide what are the failure modes associated with the alternative: wind velocity, storm

surge, traffic flow, and whether the alternative aids in evacuation and/or repopulation. ?? Use the developed framework and template to coordinate preparedness/recovery case

studies for diverse transportation systems ?? Consider the adoption for other disasters than hurricanes. ?? Consider the use of seasonal and monthly forecasts to aid in preparedness ?? Continue to update the hierarchical holographic model of hurricane preparedness and

recovery. Overall, the above framework and case studies provide support for analysis of what can be done and what should be done and what is feasible with the man-hours and the funds available to implement the preparedness/recovery alternatives.