cyber security risk assessment

Vulnerability and Risk Assessment

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5 Vulnerability and Risk Assessment

5.1 Introduction

Understanding the level of vulnerability of an asset to climate impacts is a valuable part of decision making and policy development for future adaptation, as it provides a basis for establishing priorities. For this project, the vulnerability assessment identifies the degree to which the assets would be affected by sea level rise (SLR). Section 5.2 describes the vulnerability assessment that was carried out for the selected assets.

Risk is the potential for an unwanted outcome resulting from an event, in this case from inundation from SLR. It is determined by the product of (a) the likelihood of the impact and (b) the consequence of the impact. The likelihood of an impact is, in part, a function of the likelihood of the impact (SLR) occurring. “Consequence” refers to the significance or impact to the wider region of the inundation of an asset due to SLR.

Section 5.3 describes the risk assessment that was carried out for the selected assets. During the risk assessment, (1) the vulnerability of the selected assets to SLR was reviewed in order to screen out assets that were less vulnerable to projected climate effects; (2) the likelihood of inundation occurring from SLR was assessed; (3) the consequence of the impact was reviewed, not just in terms of what the impact would do to a particular asset, but in terms of how it would affect the surrounding community and beyond; and (4) the risk rating of the consequence and likelihood occurring was determined. Section 5.4 contains the risk profiles summarizing all of the information collected on the assets that were developed as a result of the risk assessment. The process is outlined in Figure 5.1.

5.2 Vulnerability Assessment

5.2.1 INTRODUCTION

The vulnerability of an asset is related to its potential for, or its susceptibility to, damage. Vulnerability to climate change is often assessed in terms of exposure, sensitivity, and adaptive capacity. This analysis used definitions from the Intergovernmental Panel on Climate Change (IPCC 2007) for the following terms:

► Vulnerability “is the degree to which a system is susceptible to, or unable to cope with, adverse effects of climate change, including climate variability and extremes.”

► Exposure “is the nature and degree to which a system is exposed to significant climatic variations.” (For this project, this is SLR and is measured by depth of inundation at midcentury and at the end of the century.)

► Sensitivity “is the degree to which a system is affected, either adversely or beneficially, by climate- related stimuli.” (For this project, this is the physical condition of the asset. The worse the condition of the asset, the larger the magnitude of an adverse reaction to SLR is assumed.)

► Adaptive capacity “is the ability of a system to adjust to climate change to moderate potential damages, to take advantage of opportunities or cope with the consequences” (IPCC 2001, also referenced in the 2009 California Climate Adaptation Strategy [California Natural Resources Agency 2009). (For this project, one critical aspect of adaptive capacity is the ability to divert traffic onto alternative routes.)

( 5- 10 ) ( Technical Report )

( Adapting to Rising Tides: Transportation Vulnerability and Risk Assessment Pilot Project ) ( 5- 11 )

Figure 5.1 Vulnerability and Risk Assessment Process

Exposure to SLR is the primary indicator of vulnerability for this study as only assets exposed to SLR were included in the assessment, and good information was available to illustrate the potential depth of inundation that the asset would be exposed to. Due to lack of readily available information on the assets, the sensitivity or condition data was not as complete. For other climate change vulnerability assessments, the sensitivity component may be a more important indicator. Adaptive capacity must be considered carefully as part of any vulnerability assessment, as even with adaptive capacity, exposed assets can remain vulnerable. Adaptive capacity (specifically, the ability to divert traffic onto alternative routes for this project) is included as part of the vulnerability assessment. Generally, an asset that is more exposed and sensitive to a climate stimulus, condition, or hazard will be more vulnerable, whereas a system that has more adaptive capacity will tend to be less vulnerable.

In addition to setting priorities, a vulnerability analysis also provides valuable information that will aid in determining which adaptation strategies may work best, as well as determining the potential points of intervention for implementing those strategies (such as during replacement, or seismic retrofit). It also helps to identify which agencies will need to be involved in the development and implementation of those strategies as well as a variety of other issues.

( Vulnerability = Exposure + Sensitivity + Adaptive Capacity )

5.2.2 EXPOSURE TO SLR

Three maps each were produced for the 16-inch (midcentury) and 55-inch (end-of-century) SLR scenarios, as described in Chapter 4, describing six possible exposure scenarios for each asset. These maps were used to assess whether or not the asset was inundated by SLR under the different scenarios. If the maps showed a selected asset inundated at midcentury, it automatically received a high exposure rating. This midcentury exposure rating guided the overall exposure rating. If an asset would be inundated at midcentury under the 100-year stillwater elevation (SWEL) scenario, then a medium exposure rating was assigned, as it is a less likely scenario that would affect an asset on a more temporary basis. If an asset would be inundated at the end of the century under either the mean higher high water (MHHW) or 100-year SWEL scenario, it received a medium exposure rating. Note that the elevation of an asset above inundation level was not considered important for this rating, as any inundation could potentially weaken the foundations or supports of an elevated structure, therefore still placing it at risk. An asset that is inundated only under either of the wind wave scenarios received a low exposure rating. Table 5.1 and Table 5.2 outline the exposure rating assigned to each scenario for midcentury and the end of the century, respectively. Refer to Appendix B for a discussion of how the inundation depths were extracted from maps.

Table 5.1 Midcentury Exposure Rating

Midcentury Scenario	Exposed to:	Metrics	Exposure Rating
			High	Medium	Low
16” SLR + Mean Higher High Water (MHHW)	High tide levels	Depth & Extent	X
16” SLR + stillwater elevations (100-yr SWEL)	Extreme high water levels with a 1- percent return interval	Depth & Extent		X
16” SLR + stillwater elevations (100-yr SWEL) + wind wave	Extreme coastal storm event with wind waves	Extent only*			X

* The 100-year SWEL plus wind wave provides only the extent of inundation. The extent of inundation inland into Alameda County is large, and the physics of wave propagation and dissipation over land were not fully included in the analysis used to develop these maps. The limitations of the wind wave assessments and the inherent uncertainties are described in Chapter 4. Wind and wave assessments are being developed for San Francisco Bay Coastal Hazard Analyses currently underway, being performed for FEMA Region IX of the San Francisco Bay shoreline, and thus more information on this topic may be available for future subregion assessments.

Table 5.2 End-of-Century Exposure Rating

End of Century			Exposure Rating
Scenario	Exposed to:	Metrics	High	Medium	Low
55” SLR + Mean Higher High Water (MHHW)	High tide levels	Depth & Extent		X
55” SLR + stillwater elevations (100-yr SWEL)	Extreme high water levels with a 1- percent return interval	Depth & Extent		X
55” SLR + stillwater elevations (100-yr SWEL) + wind wave	Extreme coastal storm event with wind waves	Extent only*			X

* The 100-year SWEL plus wind wave provides only the extent of inundation. The extent of inundation inland into Alameda County is large, and the physics of wave propagation and dissipation over land were not fully included in the analysis used to develop these maps. The limitations of the wind wave assessments and the inherent uncertainties are described in Chapter 4. Wind and wave assessments are being developed for San Francisco Bay Coastal Hazard Analyses currently underway, being performed for FEMA Region IX of the San Francisco Bay shoreline, and thus more information on this topic may be available for future subregion assessments.

5.2.3 SENSITIVITY

Sensitivity of an asset to inundation by SLR relates to both the condition and the function of an asset. This study used physical condition to evaluate sensitivity, while data related to function (goods movement, socioeconomic impact, etc.) were used to evaluate consequence. The following physical characteristics were determined to best describe the sensitivity of an asset to SLR:

► Level of use (e.g., average daily traffic [ADT] volume [cars/trucks])

► Age of facility

► Seismic retrofit status

► Maintenance (ongoing operations and maintenance [O&M]) cost

► Liquefaction susceptibility

Information was also collected on the following other physical characteristics but ultimately not used to evaluate the sensitivity of assets:

► Condition/remaining service life - It was determined that data on remaining service life does not provide a conclusive indication of sensitivity. For instance, an asset with a short remaining service life could be characterized as sensitive, because it soon must be replaced – however, once this replacement occurs, it would then count among the assets with the greatest remaining service life, and therefore least sensitive. Since the timing of the impacts of sea level rise and of future replacement or improvements is not known, it was decided not to include “remaining service life” or age as inputs to the sensitivity rating; however, where provided this information is presented in the risk profiles.

► Foundation condition - Data was requested for foundation condition, but very little information was actually collected.

The sensitivity criteria were not appropriate for all asset types and therefore, the information for those asset types was neither available nor relevant.

This condition data also provided key input for consideration of adaptation measures, particularly for the midcentury scenario. However, based on the final quality and quantity of data received on the assets, not all of the sensitivity data were used in the development of sensitivity ratings. Therefore, sensitivity ratings

were developed based on the data collected and were compared within asset types. For example, the sensitivity of a roadway asset was compared with other roadway assets, not with other asset types, such as rail facilities. Overall sensitivities were therefore compared only within particular asset types and not between asset types. The approach for each asset type is described below.

ROADWAYS

For roadways (interstates/freeways and state routes and arterial, collector, and local streets), comparable data were generally available for the above-mentioned sensitivity metrics, except for foundation condition. Seismic retrofitting does not apply to all roadway segments and was not considered for rating purposes. In addition, the related metrics of age and remaining service life were not considered in the final ratings; older assets—though more sensitive at present—may be improved or rebuilt before SLR affects them, whereas newer assets—less sensitive today—may exhibit the greater sensitivity of older assets at the time when they are affected by SLR. Absent further information and analysis about the likely future lives of the assets, these data alone were not considered sufficient to provide a conclusive indication of sensitivity. The data points for the remaining metrics (level of use [expressed as ADT], O&M costs, and liquefaction susceptibility) were compared and separated into low, medium, and high values with respect to sensitivity. “Higher” values corresponded to higher levels of traffic, O&M costs, and liquefaction susceptibility.

If an asset had a value for one of the metrics at the low end, it received one point. If the value was midrange, the asset received two points. If the value was at the high end, it received three points. The total number of points for each asset was compared with the totals for the other assets within the asset type. Assets with a total at the low end of the totals received low ratings, assets with medium range total receive medium ratings, and assets at the high end of the totals received high ratings. Table 5.3 shows a couple of examples for interstates/freeways and state routes, and Table 5.4 shows a couple of examples for arterials, collectors, and local streets. The full list of sensitivity ratings assigned for the assets reviewed can be found in Table C5.3 and Table C5.4 in Appendix C.

Table 5.3 Sensitivity Rating – Interstates/Freeways and State Routes

Asset (Segment)	Level of Use - Average Daily Traffic Volume	Operations & Maintenance Cost	Liquefaction Susceptibility	Overall Sensitivity (H/M/L)
3 points	> 150,000	> $600,000	Very High	8 or 9 H
2 points	50,000– 150,000	$300,000– 600,000	Very High, Medium	6 or 7 M
1 point	< 50,000	< $300,000	Medium	4 or 5 L
I-80 (Powell St. to Toll Plaza)	251,000 3 pts.	$673,000 3 pts.	Very High 3 pts.	Point total: 9 H
SR 92 (Clawiter Rd. to Toll Plaza)	86,000 2 pts.	$436,000 2 pts.	Medium 1 pt.	Point total:5 L

Table 5.4 Sensitivity Rating – Arterials, Collectors, and Local Streets

Asset (Segment)	Level of Use - Average Daily Traffic Volume	Operations & Maintenance Cost	Liquefaction Susceptibility	Overall Sensitivity (H/M/L)
3 points	> 20,000	> $5.0 M	Very High	8 or 9 H
2 points	5,000– 20,000	$1.0 M– 5.0 M	Very High, Medium	6 or 7 M
1 point	< 5,000	� $1.0 M	Medium	4 or 5 L
West Grand Avenue (I-80 to Adeline St.)	22,912 3 pts.	$2.0 M (30 yrs.) 2 pts.	Very High 3 pts.	Point total: 8 H
Mandela Parkway (West Grand Ave. to I-580)	8,030 2 pts.	$1.0 M (30 yrs.) 1 pt.	Very High, Medium 2 pts.	Point total: 5 L

TUNNELS AND TUBES, TOLL, INTERSTATE AND STATE BRIDGES, AND FERRY TERMINALS

For tunnels and tubes, toll, interstate and state bridges, and ferry terminals, there are only two or three assets for each type. In these cases, professional judgment was used to assign a single sensitivity rating to each asset if they were comparable with respect to the condition metrics or to rank one higher than another if the data demonstrated a clear difference and that indicated one was more sensitive than the other.

CITY OF ALAMEDA BRIDGES, BART AND RAILROAD STATIONS, BART AND RAIL LINES, SUPPORT FACILITIES AND BICYCLE/PEDESTRIAN ASSETS

Data availability for the assessment was limited for the City of Alameda bridges, Bay Area Rapid Transit (BART) and railroad stations, BART and rail lines, and support facilities and bicycle/pedestrian assets. Only a single sensitivity metric, liquefaction susceptibility, was consistently available to assign a rating. Due to this lack of data, the project team decided to remove sensitivity from the vulnerability equation for these assets and use only exposure and adaptive capacity to assign ratings. In some instances, this led to a mixed rating (e.g., HM) (see Section 5.2.5).

5.2.4 ADAPTIVE CAPACITY

The adaptive capacity of transportation assets includes the following:

► Potential for maintaining partial use while inundated (note that this ultimately was not included in the vulnerability assessment) and

► Adequate alternative route availability to maintain function while inundated.

It was considered that assets permanently exposed to inundation would be closed to further use but that partial use may be possible in cases where the inundation is temporary or associated with extraordinary events, such as a 100-year flood event. A roadway subject to 6 inches or less of inundation, for example, could still remain in operation, although its capacity may be reduced due to slower speeds. However, the inundation mapping exercise allowed the determination of inundation depths with certainty only to the nearest foot. Thus, the data could not assess the potential for maintaining partial use, as the level of inundation separating a facility that could remain in use and a facility that would have to be closed would differ by only a fraction of a foot.

The project team discovered a lack of guidance with respect to the effect of inundation exposure on the partial use or closure of transportation facilities. In Sausalito, the on-ramps to US 101 are currently subject to recurring flooding events, under which the ramps may be inundated under several inches of water. Despite this, the ramps remain open and traffic proceeds, albeit at slower speeds, as dictated by the situation. Caltrans was contacted regarding this situation, and it was related that there are no specific guidelines in place that would determine under how much inundation the ramps (or any other Caltrans facility) would be closed. This lack of guidance made it difficult to provide a complete assessment of adaptive capacity

The adaptive capacity of an asset was therefore determined solely by the availability of (a) comparable asset(s) that could provide an alternative route or provide a similar level of functionality should the asset be closed. This included considering transit as an alternative route should a roadway or bridge be closed. (It should be noted when developing potential adaptation strategies the adaptive capacity of assets can be more broadly defined as the ability to improve resilience to sea level rise through measures such as improved drainage or coastal protection etc.)

It should be highlighted that when evaluating adaptive capacity, the project team measured the inability to adapt for consistency of assigning a high, medium, or low rating relating to a high, medium or low vulnerability, so that a high rating always meant more vulnerable. Table 5.5 illustrates the rating approach, based on the identification of nearby or parallel assets that provide alternative routes or replacement functionality for each asset at midcentury. Alternative routes at end of century were assessed but not included in the Vulnerability rating, as the condition of the transportation network so far into the future was considered too speculative to include in the rating. (It is more standard practice to define adaptive capacity as the ability to adapt, which would lead to an asset that has a high adaptive capacity, having a high rating.)

Table 5.5 Adaptive Capacity

Climate Scenario	Inadequate Alternative Route (to Show Inability to Adapt)
	High	Medium	Low
16” or 55” SLR + 100-year SWEL	No alternative route/ no comparable asset to replace functionality	An alternative route/ replacement asset is available but not fully comparable	Multiple alternative routes/comparable facilities available

In the case of linear assets (roadway segments, rail segments, and Bay Trail segments), both sides of the asset were considered to identify parallel routes that generally provide the same level of connectivity. If both “sides” provide an alternative, a low rating was given; if only one “side” offers an alternative route, a medium rating was assigned. In the case of “point” assets (bridges, rail stations, ferry terminals and facilities), the area around the asset was considered for nearby facilities that provide comparable functionality. A low rating was assigned if multiple alternatives were identified; if only one suitable alternative was located nearby, a medium rating was assigned. Thus, for example, while the BART line segments all received high ratings because there are not parallel alternative routes for BART trains, the Lake Merritt BART Station received a medium rating because if it were closed, BART passengers could still access the BART system at the nearby 12th Street Oakland City Center Station.

The ratings for the end-of-century scenario took an “if-then” approach, described as follows:

► If an asset received a high rating for the midcentury scenario, it automatically received a high rating for the end-of-century scenario (as greater inundation would not change the lack of an alternative route/replacement asset).

► If an asset received a medium rating for the midcentury scenario, and the alternative route/replacement asset would remain untouched by inundation during the 55-inch SLR plus 100-year flood event, then it also received a medium rating for the end-of-century scenario. If the alternative route/replacement asset identified would be touched by inundation during the 55-inch SLR plus 100- year flood event, then both the original asset and its replacement were considered to be similarly affected, and a high rating was given for the end-of-century scenario.

► If an asset received a low rating for the midcentury scenario, and a greater level of inundation under the 55-inch SLR plus 100-year flood event would not affect the identified alternative routes/replacement assets, then it also received a low rating for the end-of-century scenario. If the greater level of inundation at the end of the century would reduce the number of alternative routes/replacement assets to a single alternative, then a medium rating was assigned. If the level of inundation resulting from 55-inch SLR plus the 100-year flood would touch all of the identified alternative routes or replacement assets, then all were considered affected, similar to the original asset, and a high rating was given for the end-of-century scenario.

The vulnerability assessment incorporated only the ratings assigned for midcentury, although the ratings assigned for the end of the century were noted. The project team assumed that the transportation network may change considerably by the end of the century (due to adaptation strategies), so the ratings were not used to alter the vulnerability rating. Despite this uncertainty, the vulnerability ratings were not changed as a result of the rating assigned for the end of the century scenario.

5.2.5 OVERALL VULNERABILITY ASSESSMENT

As a result of the assessment exercise, each asset received a rating of high, medium, or low for each factor of exposure, sensitivity, and adaptive capacity (inability to adapt). Overall vulnerability was assigned according to the methodology outlined in Table 5.6. Some assets were not evaluated for sensitivity, in which case vulnerability was only based on exposure and the ability to re-route. The methodology for assigning vulnerability was revised during the process as described earlier in line with the data availability and in discussion with the Project Management Team (PMT).

Table C5.6 in Appendix C shows the list of assets and their respective vulnerability ratings (as well as which of those assets were selected to undergo the risk assessment process, and for which a risk profile was developed).

Table 5.6 Overall Vulnerability Assessment Method

Overall Vulnerability Score	Methodology
High (H)	Two or more highs
High/Medium (HM)	Where a sensitivity rating could not be assigned due to lack of data so only exposure and adaptive capacity ratings were included
Medium (M)	Two or more mediums or a combination of high, medium, and low.
Medium/Low (ML)	Where a sensitivity rating could not be assigned due to lack of data so only exposure and adaptive capacity ratings were included
Low (L)	Two or more lows

Table 5.7 illustrates the application of the vulnerability assessment methodology to four of the assets and the resultant ratings for exposure, sensitivity, inadequate adaptive capacity (mid century), and overall vulnerability.

Table 5.7 Vulnerability Assessment Method Applied to Select Assets

Code	Asset	Segments chosen	Exposure H/M/L	Sensitivity H/M/L	Inadequate adaptive capacity mid century H/M/L	Overall vulnerability rating H/M/L
R-01	I-80 (includes part of I-580)	Powell Street to Bay Bridge Toll Plaza	M	H	H	H
R-02a	I-880	Oak St to 23rd Ave	M	H	M	M
T -01	BART Transbay Tube		M	Lack of data	H	HM
T-04	Coliseum/ Airport BART Station	Access area and station	L	Lack of data	H	M

5.3 Risk Assessment

5.3.1 INTRODUCTION

The vulnerability assessment identified the vulnerability of the selected assets based on the information available. The next step in the process was to undertake a risk assessment of the most vulnerable assets to identify the level of risk from SLR facing the selected assets. A risk assessment typically looks at the likelihood that an asset would experience a particular impact (in this case, SLR) and the consequence of that impact on the surrounding community or region (as defined by the International Risk Assessment Standard, ISO31000:2009) It is most common to assess the risk of assets with medium- or high-level vulnerability, but for the purposes of the pilot project, a couple of representative assets rated as having low vulnerability were also moved forward to the risk assessment stage.

Generally, assets that have a low likelihood of being affected by future climate change (SLR) and a low consequence if that impact occurs are identified as having low risk, and those that have a high likelihood of being affected by future climate change and that would have a high consequence if that impact occurs are identified as having high risk. (It also allows for the differentiation between risks that have a high likelihood and low consequence, and a low likelihood and a high consequence.) Therefore, as a result of this analysis, agencies will have a risk profile associated with each of their representative assets to inform future adaptation strategies. High-risk assets will need to be prioritized for adaptation strategies, and low- risk assets will need to be monitored and revisited periodically to ensure that their risk status has not changed.

Risk Perception

Research indicates that one difficulty of conducting a risk assessment is the perception of risk: It is important to understand what it takes for people to be concerned enough to take mitigating action. A study by NOAA (2009), entitled Risk Behavior and Risk Communication Synthesis, focused on engaging the public in responding to immediate threats to coastal areas, such as evacuating before a hurricane. The study highlights risk (defined as Hazard x Exposure x Probability) as a social construct, noting that citizens’ perceptions of risk are affected by the norms of the groups that they identify with. Risk perception is based on a wider framing on topics, considerations, and agendas. It reflects personal experiences and circumstances and is highly influenced by context, such as social networks. The following points summarize some key findings, which were appropriate for consideration in the risk assessment conducted by the project team:

· There is evidence that people who are asked to compare the level of risk between various alternatives perceive risk differently from that which actually exists. Risk has two dimensions: (1) what is known about the hazard itself and (2) what is felt about it, such as the level of dread or fear. The latter can have a large influence on the perception and assessment of risk.

· From a social and cultural perspective, emerging social norms can help engage others in perceiving and responding to risk, especially if the change agents are trusted community members. Also, top- down campaigns that use a heavy-handed approach to try to convince people that they or their property are at risk are not likely to succeed and may be resented. If engaged in the risk assessment process, citizens are more likely to accept the results and to perceive their risk adequately.

· There are barriers to communicating about risk, especially for long-term, less immediate risks, such as SLR. These barriers include other, and “bigger,” more pressing problems and concerns for the stakeholders involved. Other risks, such as current financial issues, may be perceived as more important and requiring more immediate action.

For the vulnerability and risk assessment exercise of this pilot project those participating in the exercise included the organizations that made up the Transportation and Shoreline Sub Committees as described either in the report and the PMT. For these individuals, the hazard of SLR is a longer term threat to the communities and assets under their jurisdiction, but it is not a threat to their immediate livelihoods. Thus, it is expected that there are fewer emotional barriers to assessing risk/consequence of SLR. In addition, the development of guidance on how to address SLR (and legal requirements) provides the local agencies with tools to address the threat of SLR to their communities and assets, leaving the assessment of risk and development of a response less to the perception and will of individuals.

SELECTION OF ASSETS FOR RISK ASSESSMENT

As a result of the vulnerability assessment, the PMT selected the most vulnerable assets for the development of risk profiles, in order to develop two to three risk profiles per asset type. As part of this process, it was decided to combine some assets. The details of the vulnerability and consequence ratings for each of the selected assets can be found in their risk profiles (see Section 5.4).

In addition, a number of assets require special mention due to their unique circumstances, although they were not in the end selected to have a risk profile developed. The Lake Merritt BART station received a low vulnerability rating as it would not be inundated at midcentury or at the end of the century; however, it has current groundwater flooding issues that may be worsened through SLR. Future research is required to understand how this may affect its vulnerability. The Bay Trail is an asset that is highly vulnerable due to its location at the shoreline. However, it is not a typical transportation asset, so when compared to the other transportation assets, the impact of its inundation from a transportation perspective is low. The trail is nevertheless of great value to the region from a recreational perspective and provides a valuable commuting route for local populations.

( Lake Merritt BART Station and BART Operations Control Center The Lake Merritt BART Station is a transit facility serving Downtown Oakland and includes parking facilities. BART’s Operations Control Center (OCC) adjoins the Lake Merritt Station, and functions as the nerve center of the 104-mile system, performing supervisory control of train operations and remote control of electrification, ventilation and emergency response systems. Due to lack of data, these assets were not rated with respect to sensitivity. The nearby 12th Street/Oakland City Center BART Station provides another option for accessing the BART system, offering adaptive capacity for the Lake Merritt BART Station, particularly if a “bus bridge” were established between these two locations. The Lake Merritt BART Station and OCC are not subject to inundation under either the 16" or 55" SLR scenarios, making exposure not applicable according to the approach used for the pilot project. However, the underground station and adjoining facilities are subject to groundwater infiltration, and water must be pumped out under present conditions. Though not exposed to inundation as the other assets considered, consequence can be assessed for Lake Merritt BART Station using the same methodology; as a sub-grade transit facility, consequence would be high for capital improvement costs and commuter use, moderate for time to rebuild, and low for goods movement. Additionally, the OCC is vital to the operation of the entire BART system, which has regional significance and importance for transit-dependent populations. Consequence would thus be high with regard to public safety and socioeconomic impact, making the Lake Merritt BART Station and OCC, considered together, a high-risk asset for purposes of comparison. Sea level rise may have an impact on groundwater levels and flows, potentially increasing their exposure on the station and the OCC. An analysis of these impacts is beyond the scope of this project but is recommended for future consideration. )

Bay Trail and Connecting Trails

The Bay Trail provides easily accessible recreational opportunities for outdoor enthusiasts, including hikers, joggers, bicyclists and skaters. It also offers a setting for wildlife viewing and environmental education, and it increases public respect and appreciation for the Bay. It also has important transportation benefits, providing a commute alternative for cyclists, and connects to numerous public transportation facilities (including ferry terminals, light-rail lines, bus stops and Caltrain, Amtrak, and BART stations); also, the Bay Trail will eventually cross all the major toll bridges in the Bay Area. Within the subregion, the Bay Trail consists of off-street paved or gravel paths; on-street bike lanes and sidewalks; off-street unimproved paths (of varying width and surfaces). Other paved or gravel paths connect to the Bay Trail.

This project evaluated two off-street trail segments along the Alameda County shoreline: the trail around Lake Merritt connecting to the Bay Trail (the “Lake Merritt Connector Trail”) and the segment of the Bay Trail along the Hayward Regional Shoreline (the “Hayward Regional Shoreline Trail”). Due to lack of data, these assets were not rated with respect to sensitivity. Exposure for both trail segments is high (due to significant inundation under both the 16" and 55" SLR scenarios). While the Lake Merritt Connector Trail has a parallel trail, it is likely to be similarly affected by inundation; no parallel trail is available for the Hayward Regional Shoreline Trail, making the vulnerability of both trail segments high. For both trail segments, all consequence criteria have a low rating, making them low-risk assets.

Bay Trail

Bay Trail

Lake Merritt Connector Trail

5.3.2 LIKELIHOOD

Likelihood is determined by estimating the probability that a certain climate change impact will occur. For this project, the climate change impact is limited to a certain set of SLR scenarios. Since this study considered only two climate change scenarios and the project area is relatively small, the likelihood rating is the same for each transportation asset for each scenario (Table 5.8). If a range of SLR scenarios had been considered (for example, different depths of inundation expected by midcentury), then a range of likelihoods could have been identified.

Table 5.8 Likelihood Rating

Scenario	Exposed to:	Remote (1)	Unlikely (2)	Likely (3)	Highly Likely (4)	Near Certainty (5)
Midcentury
16” SLR + MHHW	High tide levels			X
16” SLR + 100-year SWEL	100-yr SWEL			X
End of Century
55” SLR + MHHW	High tide levels			X
55” SLR + 100-year SWEL	100-yr SWEL			X

5.3.3 CONSEQUENCE

“Consequence” refers to the impact on the wider region of the inundation due to SLR. The Federal Highway Administration (FHWA) pilot model guidance suggests criteria to consider consequence, including the level of use of an asset, the degree of redundancy in the system, and the value of an asset to the surrounding community (e.g., goods movement, socioeconomic impacts, and/or decreased public safety). The criteria most relevant for the Alameda County context was identified, agreed with the PMT, and ranges of consequence or impact (major, moderate, and minor) were developed for direct and indirect impacts by the project team (Table 5.9). The consequence of an asset rendered unavailable to the community and region due to inundation was reviewed by applying this set of criteria to assess each vulnerable asset. Since consequence is considered on the basis of overall impacts on the community and region, ratings were assigned by comparing all asset types using the same rating scale. Where data did not exist, professional judgment was used to assign a rating to an asset across the consequence criteria. Appendix C discusses each of these professional judgments made by asset.

TRANSPORTATION AND SHORELINE ASSET SUBCOMMITTEES MEETING

In order to verify that the consequence or impact of inundation for the selected assets had been appropriately allocated, a joint meeting of the Transportation and Shoreline Asset Subcommittees was held. The main objective of the meeting was to elicit feedback on the consequence criteria definitions and the project team assessment of consequence ratings for each of the assets. The meeting also gave the project team an opportunity to update the subcommittees on overall progress to date. Very useful feedback was obtained, and a number of the criteria were refined as a result, including the definitions of the public safety and the socioeconomic criteria, changing the impact ranking for some of the assets.

OVERALL CONSEQUENCE RATING

The project team averaged the six consequence criteria ratings for each asset to provide a final numerical rating. Although up to two significant figures were initially recorded for the consequence rating to show variation between assets, the ratings were rounded up or down for use for the overall final risk assessment (Figure 5.2). Note that averaging the consequence rating may mask the highest consequence rating so that agencies may wish in future to add a weighting to impacts that they feel are more important than others. Table 5.10 gives an example of the rating assigned for the Webster Tube.

Table 5.9 Consequence Criteria

	Major Consequence Rank 5	Moderate Consequence Rank 3	Minor Consequence Rank 1	Source of Information
Direct Asset Impact
Capital improvement cost (original cost in 2011 $) Cost to restore to same design standard/ infrastructure type	$$$$ More than $50 million	$$$ $20–50 million	$$ Less than $20 million	Agencies (e.g., Caltrans, BART, MTC), professional judgment
Time to rebuild when damaged beyond further use (if rebuilding is possible)	Length of time - long Greater than 5 years	Length of time - medium 2–5 years	Length of time – short 2 years or less	Agencies (e.g., Caltrans, BART, MTC), professional judgment
Indirect Asset Impact – Community/Regional Socioeconomic Function Impacts
Public safety: lifeline/evacuation route impact	Lifeline highway routes affected (Bay Bridge; I-80 from the Bay Bridge Toll Plaza to the project boundary)	Evacuation routes (as defined by cities) affected	Little expected impact on functionality of known lifeline/ evacuation routes	Caltrans, cities
Economic Impact (goods movement)	Major goods traffic affected	Some goods traffic affected	Minor goods traffic affected	Agencies (e.g., Caltrans, MTC),
	More than 5,000 annual average daily truck trips (AADTT)	Fewer than 5,000 AADTT	AADTT not applicable	professional judgment
Economic Impact (commuter route)	Affects medium- high-volume commuter route	Affects medium- volume commuter route.	Affects low-volume commuter route	Agencies (e.g., BART, AC Transit)
Ridership/train load for transit (ridership numbers are bi- directional)	More than 10,000 daily riders or freeway	10,000 or fewer daily riders	Assets that are not used by transit vehicles
Socioeconomic impact (transit- dependent population/ MTC communities of concern)	Asset is located in an MTC community of concern and/or in an area with low car ownership and provides access to multiple transit lines	Asset facilitates “pass through” traffic of multiple transit lines or is located in an MTC community of concern and/or in an area with low car ownership and provides access to just one transit line	Asset not located in area of MTC communities of concern or area with low car ownership, or does not facilitate transit	MTC
Recreational impact	Permanent loss of	Partial loss of	No interruption of	Not yet assessed
[Note: Not included in	some recreational	recreational access	recreational access
rating;]*	access	infrastructure/	infrastructure/
	infrastructure/	shoreline access/	shoreline access/
	shoreline access/	connectivity	connectivity
	connectivity

*Note that although recreational impact was considered, it was eventually removed from the risk profile template when it was decided to remove the Bay Trail from inclusion. This criterion had been included originally to highlight the unique benefits that the Bay Trail provides the region.

Table 5.10 Example Consequence Rating

Asset R-11: Webster Tube (SR 61) including approach ramps	Major Consequence 5	Moderate Consequence 3	Minor Consequence 1
Capital Improvement Cost (Original cost in 2011 $)	Replacement cost: $180,000,000
Time to rebuild when damaged beyond further use	Seismic retrofit took about 8 years; rebuild would take at least as long
Public safety: Lifeline/Mass evacuation route impact		Alameda evacuation route
Economic Impact (Goods movement)		535 AADTT
Economic Impact (Commuter route)	18,333 daily riders
Socioeconomic impact		MTC communities of concern and pass-through transit (multiple lines)
Total Average	4.0

The risk profiles in Appendix C show the detail of the consequence ratings for each asset.

OVERALL RISK RATING

The project team used a matrix provided by the FHWA conceptual model that evaluates both likelihood and consequence (Figure 5.2) to allocate an overall risk profile for each asset. In this project, due to the unique definition of “likelihood,” each asset received a score of 3 for likelihood and a score of from 1 to 5 for consequence, which, when added together, yields an overall score that is categorized as high, moderate, or low risk. The following examples provide more detail on the approach used:

► An asset with a likelihood rating of 3, with an overall consequence impact rating of 1 would result in an overall risk assessment of 4 (low).

► An asset with a likelihood rating of 3, with an overall consequence impact rating of 3 would result in an overall risk assessment of 6 (moderate).

► An asset with a likelihood rating of 3, with an overall consequence impact rating of 5 would result in an overall risk assessment of 8 (high).

5.4 Risk Profiles

5.4.1 INTRODUCTION

A risk profile summarizes the vulnerability and risk characteristics identified for each of the selected assets. Its purpose is to act as an information source and tool for the development and prioritization of adaptation strategies for the agencies responsible for each asset. In addition to the vulnerability and risk characteristics, each of the risk profiles contains data relating to the overtopping potential described in Section 4.3.2. Table 5.11 details the final list of risk profiles developed. Figure 5.3 provides a glossary of the information provided in each risk profile. (For a full explanation of each term, refer to the relevant parts of Chapters 4 and 5.) Appendix C presents the risk profiles for the selected assets.

	Consequence
Likelihood		1	2	3	4	5
	1	2	3	4	5	6
	2	3	4	5	6	7
	3	4	5	6	7	8
	4	5	6	7	8	9
	5	6	7	8	9	10
Risk	Low		Moderate		High

High Risk (Red) Unacceptable, major disruption likely; priority management attention required.

Moderate Risk (Orange) Some disruption; additional management attention may be needed.

Low Risk (Green) Minimum impact; minimum oversight needed to ensure risk remains low.

Figure 5.2 Risk Rating Matrix

Table 5.11 Final List of Risk Profiles, by Asset Category and Asset Type, Showing Final Risk Rating

Code	Asset Category and Asset Types	Segments Chosen	Final Risk Rating
Road Network (R)
R-01	I-80 (includes part of I-580)	Powell Street to Bay Bridge Toll Plaza	High
R-02a	I-880	Oak St to 23rd Ave	High
R-02b	I-880	High St to 98th Ave	High
R-03	SR 92	Clawiter Rd to San Mateo Bridge Toll Plaza	Medium
R-04	West Grand Ave	I-80 to Adeline St	Medium
R-05	Hegenberger Rd Airport Dr Future BART Line - Oakland International Airport Connector	San Leandro Street to Doolittle Dr Entire facility Route serving/crossing SLR exposure area	Medium Medium Medium
R-06	Powell St (City of Emeryville)	West of I-80	Low
R-07	Mandela Pkwy	West Grand Ave to I-580	Low
R-08	Ron Cowan Pkwy	Entire facility	Medium
R-09	Burma Rd	Entire facility	Low
R-10	Cabot Blvd	Entire facility	Medium

Code	Asset Category and Asset Types	Segments Chosen	Final Risk Rating
R-11	Posey Tube (SR 260) Webster St Tube (SR 61)	All, including approach ramps	High High
R-12	Bay Bridge (I-80)	From Toll Plaza until Alameda County boundary	High
R-13	San Mateo Bridge (SR 92)	From Toll Plaza until Alameda County boundary	Medium
R-14	Bay Farm Island Bridge	Entire facility, including adjacent bicycle bridge	Medium
Transit (T)
T -01	BART Transbay Tube	Entire facility	High
T -02	Elevated BART Line between Transbay Tube and Oakland Wye	Elevated structure between I-880 overcrossing and I-880 undercrossing	Medium
T-03	West Oakland BART Station	Entire facility	Medium
T-04	Coliseum/Airport BART Station	Entire facility	Medium
T-05	Oakland Jack London Square Amtrak Station	Entire facility	Low
T-06	UP Martinez Subdivision	Emeryville Segment (I-580 to 14)	Medium
T-07	UP Niles Subdivision	Oakland Segment (17-23)	Medium
T-08	Jack London Square Ferry Terminal	Entire facility	Low
T-09	Alameda Gateway Ferry Terminal (including Park &Ride, bike, ADA access)	Entire facility	Low
Facilities (F)
F-01	AC Transit Maintenance (1100 Seminary)	Not Applicable	Medium
F-02	Burlington Northern Santa Fe Intl Gateway Intermodal Yard	Not Applicable	Medium
F-03	Capitol Corridor Norcal O&M Yard	Not Applicable	Medium
F-04	7th Street Highway and Railroad Pumps	Not Applicable	Medium

( Asset Location/Jurisdiction Location of the asset in the region/agency responsible for the asset Summary Summarizes the technical information on the risk profile in a couple of sentences Characteristics This section lists the functionality of the asset selecting from: Lifeline route Mass evacuation plan route Goods movement Transit routes Bike route Commuter route Regional importance Socioeconomic importance: supports transit-dependent populations )Risk Profile Glossary

Images shown on each risk profile

· Context map showing where the asset is in the subregion

· Photograph(s) of the asset

· Map thumbnail showing projected inundation with 16-inch SLR + 100-yr SWEL

· Map thumbnail showing projected inundation with 55-inch SLR + 100-yr SWEL

· Map thumbnail showing projected overtopping with 16-inch SLR + 100-yr SWEL (light blue)

· ( Sensitivity: Low /Medium/High – provides the overall sensitivity rating allocated for the asset Year Built Year Level of Use Peak Hour AADT (Annual Average Daily Traffic AADTT (Annual Average Daily Truck Traffic) Number Seismic Retrofit Yes / No Annual Operations & Maintenance Cost $ Liquefaction Suceptibility VH = very high H = high M = moderate L = low Exposure: Low /Medium/High – provides the overall exposure rating allocated for the asset Maximum Inundation Depths 16” + MHHW 16” + 100-yr SWEL 16” + 100-yr SWEL + wind waves ft ft Yes/No 55” + MHHW 55” + 100-yr SWEL 55” + 100-yr SWEL + wind waves ft ft Yes/No Inadequate Adaptive Capacity (16” SLR): Rating Notes on alternative routes available if asset is inundation Vulnerability Rating ( midcentury ) : Low /Medium Low / Medium/ Medium High / High )Map thumbnail showing projected overtopping with 55-inch SLR + 100-yr SWEL

*Note that there may be symbols in the thumbnail images that are not explained – for the full legend please see the inundation and overtopping maps in Chapter 6.

Risk Profile Glossary

Consequence Rating (out of 5): Number between 0 and 5 Ranges of consequence or impact - major (5), moderate (3) and minor (1) were developed for each of the impacts below.
Capital improvement cost	Cost to restore to same design standard/ infrastructure type.
Time to rebuild	To original condition, based on 84-, 60-, and 24-month estimates
Public safety	Lifeline or evacuation route
Economic impact - goods movement	Based on average annual daily truck traffic (AADTT) data
Economic impact - commuter route	Daily ridership figures (also all freeways, bridges, tubes assigned major impact)
Socioeconomic impact	Based on MTC communities of concern, MTC data on household car ownership and whether providing a transit route
Risk Rating: High / Medium / Low (from combination of “likelihood” and “consequence”) rating

Shoreline Asset “Overtopping” Analysis (see Section 4.3.2 for more detail)
Proximity of transportation asset to overtopped shoreline asset (distance)	16” + 100-yr SWEL
	ft Transportation assets that are closer to the shoreline could have a higher likelihood of future inundation
	55” + 100-yr SWEL
	ft
Length overtopped (% of system)	16” + 100-yr SWEL
	ft (%) The greater the percentage, potentially the more at risk the asset is
	55” + 100-yr SWEL
	ft (%)
Average depth of overtopping	The average depth of inundation along the overtopped portion of the shoreline assets within a particular system. Portions of the shoreline system that are not overtopped (overtopping depth = 0) are not included in the average overtopping depth calculation. As sea level rises from the 16” to 55” SLR scenarios, additional lengths of shoreline are inundated within each system; therefore, the average overtopping depth increase between the two scenarios is less than the 39” increase in sea level.
	16” + 100-yr SWEL
	ft The deeper the overtopping, potentially the more at risk the asset is
	55” + 100-yr SWEL
	ft
System responsible for inundating transportation asset (See overview map)	Number of System: The study area is divided into 28 shoreline “systems” – contiguous reaches of shoreline that act together to prevent inundation of inland areas, ranging in length from approximately 1 to 18 miles. Section 6.5

( Description of any future projects anticipated for the asset . )

( Future Projects )Figure 5.3 Risk Profile Glossary: Asset Name (Asset Code)

5.5 Recommended Refinements to the FHWA Conceptual Model

5.5.1 LESSONS LEARNED

DATA COLLECTION

As mentioned in Chapter 2, due to the large number of important transportation assets in the project area, extensive data collection requests related to specific transportation assets were delayed until the asset list had been shortened so that agencies were not overwhelmed by the data requests. This included the information required to assess the condition of the asset to inform the sensitivity component of the vulnerability analysis (such as its age, whether or not it had been seismically retrofitted, its annual O&M budget) and the potential impact of inundation to inform the consequence component of the analysis (such as cost and time to rebuild). Data were sometimes also received after deadlines set by the project team, which led to the need for repeated updates to the inventory and to both the vulnerability and risk assessment exercises. The amount of effort and time required to collect data should not be underestimated.

DEFINITIONS

The methodology used for the vulnerability assessment was a truly iterative process, due to the number of approaches to vulnerability assessment and the number of interpretations of some of the key terms (even between different papers produced by the Intergovernmental Panel on Climate Change). For example, some approaches consider adaptive capacity as part of the vulnerability equation, and some do not, assuming that this could mask the true vulnerability of an asset. The project team had extensive discussions to work out what the most appropriate approach was for the project area and assets, bearing in mind the information available. For example, the team originally considered both the potential for maintaining partial use of an asset while it was inundated and the availability of an adequate alternative route to maintain function while the asset is inundated as important components of adaptive capacity of a transportation asset. But this was revised to just refer to the availability of an adequate alternative route. Initially, the project team considered that adaptive capacity should be considered as part of the consequence of inundation (if the asset has adaptive capacity, it is of lower consequence to the region) but finally concluded that as long as low-cost adaptive capacity measures only were considered, it should be part of the vulnerability equation.

INTEGRATION OF SHORELINE ASSETS INTO THE ASSESSMENT

If and how the performance of the shoreline assets should feed into a vulnerability assessment was also a topic of much discussion. Using the inundation mapping information generated for the project, it is possible to look in detail at which shoreline assets were overtopped where and to what depth, providing useful information for future adaptation strategies. It was decided, however, that there was not sufficient information available regarding the likely future maintenance, and upgrade schedule for the shoreline assets to understand with confidence how the overtopping potential may affect the vulnerability of the assets. It was decided in the end that this information would be best utilized as a tool to help figure out the most appropriate adaptation strategies to protect the transportation asset. Knowing how much and to what depth the closest shoreline protection system was overtopped would allow both the prioritization and the development of the most appropriate adaptation strategies. This is an indication of the adaptive capacity of the shoreline assets.

TREATMENT OF DIFFERENT ASSET TYPES

At different points in the process, assets were compared within or across asset types. When sensitivity data were reviewed, in order to develop sensible ranges of low, medium, and high, assets were compared within ranges (e.g., in terms of cost, replacement time). When reviewing consequence impact data, assets were compared across asset types to ensure comparison of truly comparable assets and to assist in appropriate prioritization.

There was much discussion regarding how to assess the Bay Trail and other pedestrian or bicycle infrastructure in terms of impact or consequence of inundation from SLR. Although the Bay Trail is of great importance as a recreational and social asset for the local community and is a valuable commuting route for some, when compared to other transportation infrastructure, such as freeways or the Bay Tube, it cannot compete in terms of regional transportation significance. For the risk assessment exercise for this project as described above, all assets were compared using a common scale in order to use the assessment as a prioritization tool. The Bay Trail was carried through the vulnerability assessment stage as an important representative asset for the region and was determined to be highly vulnerable. However, when assessed with the consequence criteria, it was determined to have low impact or consequence (because it would be comparatively inexpensive to rebuild and does not carry significant commuter or goods traffic) relative to other assets. Given the trail’s importance to the region (even though not from a regional transportation perspective), the project team decided that it was not appropriate to label it of low consequence if it were inundated. (It should be noted that for other projects, if prioritization or comparison is not made across asset types, then metrics can be developed to enable assets to be compared within their asset types.)

5.5.2 RECOMMENDATIONS FOR FUTURE APPLICATIONS

Recommendations for the vulnerability and risk component of the process include the following:

► Provide fuller definitions or guidance on what exposure, sensitivity, and adaptive capacity mean and how to use them for different project types.

► Obtain early input from stakeholders on definitions of the consequence impact criteria as this insight is valuable to ensuring that criteria are tailored to the local context. For example, during the project, the definition used for “public safety” was expanded from a defined California Department of Transportation lifeline route to include routes that were identified as emergency evacuation routes by local cities.

► Provide guidance about whether or not agencies may wish to add a weighting to certain impacts in the instance that multiple impacts are being rated and averaged to provide an overall consequence rating which may mask the highest (and most concerning) consequence rating

► Organizational impacts to the agencies themselves are not included as consequence criteria and should be considered in the future. Decisions made by agencies today that increase the vulnerability by not taking climate change into account may led to liability issues in the future.

► Provide guidance and examples on how to rate the sensitivity of an asset when the availability of data is inconsistent between assets.

► Provide guidance on how to include consideration of the impact of potentially accelerated asset deterioration due to e.g. temporary inundation during storm events

► Provide guidance and examples on the methodology developing the ranges (major – moderate – minor) for rating assets against different consequence criteria, particularly when qualitative data may be hard to obtain, yet participants are not comfortable using professional judgment to rate an impact.

► Ensure that asset types only of comparable scale/class are included in the same assessment.

► Provide guidance on when it is appropriate to assess assets across asset types and when it is appropriate to assess assets within asset types.

► Provide guidance on the range of asset types that should be included in a project scope so that like- with-like comparisons can be made.

► Agencies should put in place data inventory development processes to consolidate data about transportation assets to facilitate future risk assessment exercises.

► Include guidance or suggestions on what type of more detailed inundation mapping can be helpful for prioritizing vulnerable assets and understanding how the protection that a shoreline asset is offering changes with SLR.

► If more detailed inundation mapping is done for projects looking at SLR in particular, ensure that time is factored into the schedule to account for this.

5.6 References

California Natural Resources Agency 2009. 2009 California Climate Adaptation Strategy. IPCC Fourth Assessment Report: Climate Change 2007 (AR4) IPCC 2007

IPCC Third Assessment Report: Climate Change 2001 (TAR) IPCC 2001

Risk Behavior and Risk Communication: Synthesis and Expert Interviews Final Report for The NOAA Coastal Services Center Betty H. Morrow, Ph.D. SocResearch Miami July 2009

Knowles, Noah. 2009. Potential Inundation Due to Rising Sea Levels in the San Francisco Bay Region. A Paper From: California Climate Change Center (CEC-500-2009-023-F), March 2009.