Skip to content U.S. Department of Transportation/Federal Highway AdministrationU.S. Department of Transportation/Federal Highway Administration

Office of Planning, Environment, & Realty (HEP)
PlanningEnvironmentReal Estate

HEP Events Guidance Publications Awards Contacts

The Gulf Coast Study, Phase 2

Key Determinants of Criticality

The project team's interest in identifying critical assets represents the first phase of a vulnerability screening process. Moreover, this process is intended to be transparent and replicable so that other jurisdictions interested in considering the impacts of climate change may borrow lessons learned and methods used in Mobile as they attempt to narrow the range of assets they consider.

Before the level of criticality of an asset can be determined, the term "criticality" itself must be clearly defined in the context of such an assessment. Traditionally, assessments of criticality may connote notions of risk but, in this case, critical assets are intended to include the assets of greatest importance. In this sense, criticality may relate to economic importance, access to jobs or healthcare facilities, emergency evacuation routes, social connectivity, cultural significance, or other core values. The extent to which each of these elements of criticality is included in such an assessment must be a reflection of the goals of the decision-makers who will ultimately use the information. In a case like this, where the focus is on a particular county, the assessment had to balance local priorities with information more applicable to other audiences as well.

Prior work on identifying critical infrastructure in other parts of the U.S. has focused primarily on major transportation facilities that serve a national purpose - primarily interstate travel and trade.[1], [2] However, assessing what is critical to a local area - i.e., the Mobile MPO area - requires that other criteria be taken into consideration, such as those related to community and economic viability. Recognizing interstate travel as the sole criterion for asset criticality might not capture the full measure of important transportation assets that support the economy of Mobile County and surrounding counties. Acknowledgement of regional and local transportation connections (including major port facilities and railroad operations), and their importance to the community, is necessary.

To ensure that the assets defined by the project team reflected the local priorities and values of the Mobile community, stakeholders were engaged at several points to help define "critical" for the purpose of this study. A draft methodology was developed by the project team, in collaboration with USDOT, and presented to the CCWG to get their input on process. Feedback provided by the CCWG was incorporated into the final methodology that was applied during the inventory and scoring stages.

Stakeholder input was also vital during the review of preliminary results of the criticality assessment. During presentation of the draft results, stakeholders noted that certain assets that were regionally important (i.e., important beyond the confines of Mobile County) were not designated as highly critical based on the quantitative assessment. Local stakeholders also identified examples of assets with cultural importance, but which had not been deemed critical through the objective scoring process. These comments demonstrate the importance and value of engaging stakeholders in developing criteria for screening assets, as well as any "on top" adjustments to reflect qualitative realities that are not able to be captured in a quantitative "desk-based" assessment. The "Locally Specific Criteria" discussion at the end of this section expands on this issue.

For the purpose of this study, the determination of criticality of transportation assets in Mobile was based on the following categories of criteria:

Specific criteria within each category are discussed in more detail below.

Assessing Socioeconomic Importance

The socioeconomic importance of an asset relates to how it contributes to the social viability of the community, as well as its role in supporting the local economy.

Social Viability

Social viability involves measuring the importance of transportation assets to the community in terms of providing access to facilities that allow the community to function. A community is comprised of more than just its economic base. Many individual components including households, schools, libraries, government centers, retail establishments, places of worship, and other locations define a community as a whole. The role of transportation in providing connectivity between those destinations is well defined and enables community viability and livability. Figure 2 illustrates the location of various community facilities such as schools, colleges and universities, emergency service locations, government institutions, and health care facilities in the Mobile study area.

Connections to these facilities were factored into the criticality analysis in recognition of their importance to community function. For example, the project team reviewed the transportation links connecting the community to schools and government facilities. The project team also engaged the assistance of local stakeholders who identified other key transportation links such as the connection to Bayou La Batre, Dauphin Island Parkway and Route 43 connecting to the industries along the corridor. More details on this process are provided under the highways discussion in the "Detailed Methodology and Results by Mode" section.

The project team recognized the limitations of adhering to quantitative criticality criteria when considering community linkages. Therefore, direct community input on a preliminary round of criticality scores was solicited. Stakeholders were given the opportunity to adjust some criticality scores upward based on their importance to the community. The "Incorporating Local Values" section describes the changes that were made and lessons learned from this exercise.

Economic Viability

Economic viability involves an asset's role in supporting commerce[3] and providing access to major employment destinations. For purposes of this assessment, an asset's role in supporting the local economy in Mobile was the primary focus; however, assets such as ports and rail facilities can support commerce in Mobile, across the Gulf Coast region, and across the country, and so the rating criteria are designed to reflect this broader potential importance. Examples of critical commerce links in the study area include trunk rail lines, multi-modal linkages such as roads serving port facilities, and major truck routes. Major employment destinations in the study area were also identified and access to them made part of the criticality analysis. This assessment considered large individual employers as well as clusters of smaller employers that, together, formed major employment sites. Access to these facilities was considered to be an important criterion across multiple modes as the support of the economic base is a critical measure of the transportation system. More information on the economy of the Mobile area can be found in Appendix A.

Assessing Use/Operational Importance

Operational importance was assessed by considering the use of each link in the transportation network, its capacity, and the importance of the operations that the asset supports to the Mobile County economy[4]. Examples of use measures include average daily traffic (ADT) along roadways, ridership for transit, annual gross tonnage for rail lines, and cargo volumes for ports. More detailed information on operational importance can be found in the "Detailed Methodology and Results by Mode" sections throughout the report.

Assessing Health and Safety Importance

Health and safety considerations include the asset's role in evacuation plans; disaster relief and recovery plans; the asset's role in moving hazardous materials; inclusion in the national defense system; and the extent to which an asset provides access to health care facilities.

Figure 2: Community Resources

Figure 2 is a map of the study area that shows the locations of primary schools, secondary schools, colleges and universities, medical facilities, and government and emergency services. Collectively, these facilities are called “community resources.” The map also shows the major rail and highway routes to illustrate where these routes are in relation to the community resources. The community resources are concentrated in the Downtown Mobile area, and become more scattered the farther away from Downtown they are. Primary schools and government and emergency services have the greatest number of facilities in Mobile. The map shows that many community resources are located near major highway routes, although there are also many resources located along less major routes as well.

Incorporating Local Values

The methodology to determine criticality by mode was developed to capture as much objective data as possible to help inform decisions on which individual links or nodes of the various transportation systems were most important when compared to the networks in their entirety. This methodology included analysis of census data, compilation of an extensive GIS database, and feedback in interviews conducted for the purpose of understanding the utilization of each network link. Furthermore, the approach used in Mobile focused primarily on assets that are highly important to Mobile County or (for some modes) that play key roles in commerce or the movement of people in the state, the Gulf Coast region, or nationally. Therefore, the approach initially had more limited sensitivity to the importance of assets to local communities within Mobile County.

The scores resulting from this analysis were presented in matrices and presented to local stakeholders for feedback. The feedback provided by the local stakeholders was very informative. It was noted that certain important assets/areas had not been captured through the assessment process. In particular, it was noted that a few assets/areas that, in stakeholder opinion, defined Mobile had not been included. Specifically, the sense was that the project team had not adequately reflected the importance of access to: the Bayou La Batre port and related seafood industry activity, Dauphin Island, and large employers along the Highway 43. Stakeholders also noted how vital the local port facilities were to the Bayou La Batre community. None of these areas stood out as overall major contributors of jobs (from the County perspective) based on Census economic data; however, stakeholders were concerned that the study was not adequately capturing the economic benefits and social importance of these areas. Adjustments were therefore made to the criticality list.

In each case, the matrix developed for this analysis provided the flexibility to rank components of transportation infrastructure using a range of methods. When applied in other areas, the matrix could include weightings for each criterion that reflect items of particular importance. Decisions on what is important from a purely economic perspective, from a community cohesion perspective, or from a local accessibility perspective could drive decision-making on defining critical networks when applied in other areas. In the field, a study like this would begin with an agreement on the reasons for screening for criticality, the scope of influence the interested party or parties may have (e.g., all modes, one mode, operations, asset management, maintenance, planning, design) and the impetus for making changes (e.g., health and safety concerns, economic concerns). This task was intentionally made to be broad to encompass all modes and provide even treatment of emergency management, operations, and socioeconomic factors. The value of a systematic approach for assessing infrastructure for criticality is that it creates a baseline for decision-making and presents a tool to help streamline efforts to assess vulnerability and risk.

The project team has concluded that the effort to identify critical infrastructure would have benefited from a slightly revised form of stakeholder input. In the future, the project team would recommend holding a facilitated discussion of the draft (desk review) findings. This conversation would encourage dialogue on specific asset scores on criteria of interest to local stakeholders and would ensure that considerations not expressly included in criteria get factored into the findings early on.

Updated: 03/27/2014
HEP Home Planning Environment Real Estate
Federal Highway Administration | 1200 New Jersey Avenue, SE | Washington, DC 20590 | 202-366-4000