In February 2001, an earthquake (magnitude 6.8) occurred in the Puget Sound region of the state of Washington. In October 2003, a fast-moving, uncontrollable wildfire blackened more than 270,000 acres of the county and city of San Diego.
In May 2004, a warehouse holding a large inventory of a product containing chlorine burned to the ground near the town of Rockdale, Ga. In late January and early March 2005, abnormally high levels of precipitation suddenly created hazardous traveling conditions in several parts of the Moapa Valley in Clark County, Nev., including flooding of a small town in a river valley, avalanche conditions in the mountains and closing of state routes in rural areas as well as along the fringes of Las Vegas. Also in March 2005, a railroad tank car parked in south Salt Lake City, Utah, began leaking as it was eaten away from the inside by an unidentifiable mix of chemicals.
What did these emergency events have in common and what were the implications for the states’ transportation agencies?
For one thing, each of these emergencies represents what is referred to here as a “no-notice” event to distinguish them from events for which there is an appreciable time prior to impact to provide information to the public. Secondly, all of them resulted in total closures of all lanes in both directions of interstate and state highways for long periods of time even though none of the events represented a traffic-related incident that originated on the highway. All but the earthquake prompted evacuations of one or more neighborhoods. No-notice events such as these create immediate information needs for the public so they can react to the conditions quickly without hours or days of advance warning.
Case studies were conducted at the five sites in a project for FHWA titled “Communicating with the Public Using ATIS during Disasters,” which is part of the Intelligent Transportation Systems (ITS) Emergency Transportation Operations (ETO) initiative [www.its.dot.gov/newinit_index.htm] of the U.S. Department of Transportation. The objective of the project is to understand what information needs to be communicated during disasters and how advanced traveler information system (ATIS) assets can figure in delivering information at such times.
The following sections describe the disaster situations and how information dissemination was carried out during the disasters.
Events of emergency
The five disasters are discussed below in terms of uncertainty, duration, scale and availability of information dissemination assets as the context in which information dissemination occurred.
Uncertainty surrounding the event
Each of the five events, defined as a disaster in the study, had a sudden onset providing minimal or no time for authorities to tell the public in the vicinity of the event what to expect before the event began to disrupt activities in the area. The authorities themselves were uncertain initially about what was happening or what the scope of the situation would be in the near and long term. While incident commanders were making initial assessments of the nature of the event and associated risks, general precautionary measures were implemented to keep the public out of range of obvious or potential hazards. These measures included quick temporary evacuations of neighborhoods and closures of highways, roads and streets to general traffic (but not emergency responders) in areas where travelers might be in danger created by the disaster event.
Duration of the event
Along with the sudden onset, the highway closure in conjunction with the potentially dangerous phase of the disaster event was of fairly long duration, ranging from 14 hours to several days, and required ongoing delivery of information about travel conditions to the public. Usually a highway was closed until the responders declared the situation over, or at least no longer a source of danger to the public. During this time, people at home, work or traveling needed information with which to make decisions about adjustments they might make in their activities until the situation was resolved. In some cases, the residents in the vicinity of the event needed information about an evacuation order and the available routes. Travelers, including commuters, tourists and truckers, needed to know how long they would be delayed or which other routes were open and safe.
Scale of the disaster
The extent of disruption created by each of the five disaster cases ranged from a portion of an urban area to several counties and had implications for the scope of information dissemination to the public. From the perspective of the transportation agency, the scale of the event varied in terms of how many miles of roads had to be kept closed, in how many places at once and under whose jurisdiction. In order to keep travelers, including truckers, moving to their destinations, the transportation agency needed to plan and provide signage for one or more detour routes. The chemical fire in Rockdale provided an example of how complicated this can be. The closure of I-20 extended across several exit ramps. Because the smoke plume hovered along the highway, both eastbound and westbound traffic had to be detoured around approximately 20 miles of the closed interstate. In the lightly settled area, it took the Georgia DOT three hours to thread the detours along only state routes, as required, place the signage and test the two routes.
Availability of information assets
In general, the closer the associated highway closures were to a major urban area the more technological assets (such as traffic management centers [TMC], cameras and variable message signs [VMS]) were available to monitor and direct traffic flow and the more transportation and law enforcement staff and equipment were available for closures and detours.
In all five disaster locations, the transportation agencies made road information available via a toll-free telephone number, a website and VMS, even though some assets, such as VMS, may not have been available to people in the immediate vicinity of the disaster. Only one site had a functioning highway advisory radio (HAR) during the disaster event.
Not a normal traffic incident
In each of the disaster cases studied, transportation and public safety agencies were faced with much more complex and extended challenges to their capabilities and resources to manage response, public information and traffic than is typically the case for a traffic incident. With the exception of the earthquake case, the risks to travelers were created by something happening near but not on the road. Under these circumstances, the transportation officials are responding to information from another agency that the area, including the road, is unsafe. It becomes difficult for the transportation agency to make judgments and take action to keep traffic moving, as it can in the case in a normal traffic incident.
For example, during the Cedar Fire in San Diego County, California DOT (Caltrans) opened and closed roads based on information from the incident commander about where the fire was likely to go next. The Caltrans crews moved portable VMS and barriers around to close dangerous stretches of road in response to the requests from the incident commander and then used their own expertise to determine if a road was safe for vehicles once the fire had passed over it before opening it again to traffic. During all these decisions and actions, the DOT information about road closures and conditions needed to be continuously updated.
Passing information
As the disasters played themselves out, the public needed to be informed. This section discusses how information dissemination was carried out.
Role of the media
The predominant form of information dissemination in all five sites was through the mass media channels, particularly television. Reporters used various means to obtain information about the event, and the agencies involved in the disaster response, including the DOTs, attempted to facilitate the mass media’s access to information. Working with the media was important to agencies for enhancing the accuracy and consistency of the information reported on radio and television and for enlisting the mass media as a means of providing instructions to the public about priority safety actions called for in specific areas, including evacuation.
Agencies involved in the disaster response typically had their own public information officer who dealt with the media, but each agency was careful to discuss with the media only the status of activities of their particular agency.
Information was provided either directly to reporters near the scene or as part of media briefings for which status information from across the responding agencies was collected to be presented all at one time or through electronic means.
Use of ATIS
The ITS devices used by transportation agencies on a day-to-day basis for reporting traffic conditions were put to work for the provision of information about locations of delays or road closures related to the ongoing disaster. The ATIS assets used by the agencies for the disaster-related road closures are indicated in Table 1. All five sites used at least three means for providing traveler information in response to the road conditions created by the event. All but one DOT operated its TMC and ATIS on a 24-hour basis, which meant that newly updated messages about the status of a road could be provided within minutes.
The amount of information that was provided to travelers about appropriate action and the method used to impart the information varied considerably depending upon the traveler’s location and the agency assets available. For example, when I-15 was closed north of San Diego because the cedar fire had burned up to it and then jumped to the other side, Caltrans was able to use its overhead VMS in that area to alert travelers that they needed to exit the highway.
The VMS were supplemented by on-the-ground personnel who positioned drums and cones to remove lanes in advance of the exit, and California Highway Patrol officers were posted for enforcement. Further from the city, travelers on the state routes in the rural areas were directly informed about the sudden fire-related closures by the portable VMS placed and moved as needed by Caltrans’s Traffic Management Team. Travelers and evacuees on the county roads were directed by members of the sheriff’s department and by barriers and signs placed by county public works staff.
Existing toll-free telephone systems and websites for reporting road conditions were brought into service to provide the traveling public with information about road closures. Thus, travelers aware of those systems could have obtained information before they set out or, using a cell phone, while they were en route. It is interesting to note that highway advisory radio (HAR) was used in only one of the five locations.
Statistics for use of the Utah DOT’s 5-1-1 telephone system and CommuterLink website on March 6, 2005, the date of the leaking railcar event, showed higher usage compared with most other Sundays, thus indicating that people were accessing these ATIS sources of information about the roads.
March 6 had a higher number of callers seeking traffic information than the typical Sunday (Figure 1), and usage of the UDOT CommuterLink website also was greater on March 6 than on other Sundays that month (Figure 2).
Source of ATIS information
In all but one site (southern Nevada), the TMC of the DOT operated 24 hours during the disaster. Their normal practice of monitoring radio transmissions of the state’s highway patrol was one of the first alerts to an actual or potential disruption of traffic flow. In the urban areas, ITS devices such as highway cameras and traffic detectors also served to alert TMC operators that something was causing a change in traffic flow. TMC operators were responsible for using their information sources for developing messages to place on their ATIS devices and updating them as necessary throughout the disaster event. Messages were directly related to the road condition and traffic routing, but standard operating procedures restricted the operators from providing information about the disaster event causing the road problems.
Interagency response
In some of the sites, where a large number of agencies and jurisdictions were involved in the response and the duration of the response promised to be of longer duration than a few hours, one or more cities or counties activated their emergency operations center (EOC). At these EOCs, agency representatives in touch with the operations of their agency in the field shared information and worked on plans for providing resources as needed by the incident commander for the response. Either a transportation agency representative or a law enforcement official was present to provide specific information about the activities of the transportation agency and road closures.
The activation of an EOC also facilitated the use of a joint information center (JIC) function for compiling information across agencies. The advantage of a JIC is that it can schedule and hold periodic briefings for the media in an effort to promote the dissemination of accurate and consistent information about the combined efforts of the response agencies.
For example, agencies in Utah did not initially establish a JIC, but as the disaster event wore on and threatened to disrupt the Monday morning rush period a JIC was formed. The EOC managers and incident commanders also remarked, however, that the television reporters, in particular, will still prefer to gather their information at the scene. Thus, the incident command team needed to have a person and a process for periodically providing status reports and answering questions on the spot, again for the purpose of achieving greater accuracy and consistency. The public information officers included in the interviews stressed that in recent years the response agencies have strived to create a strong interface with media agencies in order to be able to count on news reports to not only be accurate but to provide instructions about safe behavior to the public.
In with command
State and local transportation agencies play an important role in aiding the public during the disasters. Roadways and transitways are needed for evacuating populations at risk and for helping travelers avoid threatened areas. ATIS assets can help with this task by serving as an information dissemination mechanism while travelers are en route or before they set out.
The transportation agency’s principal responsibility during a disaster is to assess how best to deploy transportation assets to keep travelers safe but also moving. The agency gets information about road conditions primarily by monitoring information from its own ITS technologies, monitoring of law enforcement communications and its own personnel.
More than one transportation agency person interviewed for this study mentioned that there can be benefits from the transportation agency taking a more active role in the decision making with the incident command team than has typically been the case.
Generally, the assessment that a particular area—including roads—is not safe comes from the incident commander. The people carrying out the response operations at the scene (or scenes) of the disaster have the best information about what is going on and what may happen because of this. The transportation agency can better plan its overall strategy for keeping traffic out of the dangerous area for a fairly long term (e.g., through the next day’s morning commute) if it is present as the assessment of current and future conditions is being discussed. The agency’s traffic engineers can work on a broader strategy as well as the specific tactics for carrying it out, and the TMC operators can use this to develop appropriate messages and traffic alerts for dissemination using ATIS devices.
At the same time, TMC staff interviewed for the study emphasized that they had very limited resources for obtaining timely information from areas beyond that covered by their ITS assets, which limits the information that can be disseminated using their ATIS dissemination technologies. In rural areas, the ability to receive and disseminate timely information about suddenly emerging road hazards is greatly limited. Even in many urban areas information on the status of nonstate roads and city streets operated by local county and city agencies is currently very limited.
To assist public agencies in their planning for and management of disaster situations, the project, of which the case studies reported on here are a part, is intended to support their efforts in delivering information to the public to help them travel during the response and recovery phases. Already published is a concept of operations of ATIS in disaster management (http://www.itsdocs.fhwa.dot.gov//jpodocs/repts_te//14262.htm) that incorporates the findings from the case study along with results from a workshop with transportation and emergency management professionals. The final publication will be a guidance document that will summarize the findings of the entire project and provide a toolkit to assist agencies in developing a strategy for best utilization of their ATIS assets during disasters.
