Step-By-Step Manual

The objective of the assessment can be drawn from the objective of climate proofing detailed in Step 1 “Scoping of climate proofing” and will guide establishing the risk assessment approach. Hence, whether risk assessment is carried out for developing a climate resilient infrastructure investment plan or designing feasible new project or stress test existing infrastructure is a decisive factor that defines the way a risk assessment is configures (compare chapter 4).

Overall, three types of different scopes and context of assessment can be differentiated:

• Understanding the risk of service reliability and performance of the portfolio of newly planned or existing infrastructure, considering different geographies.
• Understanding the risk of structural integrity and operational robustness of the portfolio of newly planned or existing infrastructure, considering different geographies.
• Understanding the economic risk of the of the portfolio of newly planned or existing infrastructure, considering different geographies.

Sometimes, all objectives might be covered in a single assessment, the scope opens wide then, or there is a particular interest in one of these that allows for more in-depth assessment using specialized techniques.

Questions related to objective:

• Is the element, and its sub elements, relied upon for delivering services across a jurisdiction?
• In the event of a climate impact would damage and/or loss of function to the element cause concern for public safety?
• Has the element, or any of its sub elements, previously been defined as critical via government processes or otherwise?

Is the element, or any of its sub elements, not necessarily owned or maintained by the risk assessment lead but still considered important by stakeholders and residents (e.g., cultural heritage)?

Box 3 Example of objectives and context of dam infrastructure assessments

Example 1: Assessing structural integrity as an objective: Hydrological safety assessments are necessary to prevent a failure of water infrastructure, in particular dams. Results of the hydrological safety assessment are necessary inputs for the geotechnical safety assessments, which consider the stability of the dam against sliding, turning, base failure. All assessments feed into to design of a water infrastructure or help devise rehabilitation measures in case safety standards are not met. Specifically, dams require a comprehensive safety assessment. The hydrological dam safety analysis consists of three pillars: hydrological modelling, regionalization, and worst case probable maximum flood (PMF).

Example 1: Assessing service reliability as an objective: NBI took the lead in executing a service reliability assessment of six infrastructure projects at pre-feasibility and feasibility stage from the NEL Investment Programme (NELIP). Due to the important services which serve as main objectives of the projects, it was necessary to study the effects of climate change on the hydrological regiment in the respective rivers to be able to assess the risk on the reliability of the provided services. The relevant infrastructure services of these projects were hydropower, municipal and industrial water supply, irrigation, flood control and e-flow.

Assessment criteria will identify key details for the assessment. These include:

• Asset details and boundary conditions
• Level of service standards
• Importance or criticality of assets and sub elements
• Time horizon of the assessment
• Geography or geographies of a portfolio (considering different climate regions)
• Governance and jurisdictional considerations
• Assessment process selection or screening

An important decision needs to be taken about defining the scale of the assessment. For water infrastructure the scale could be for example, the dam scale, the reservoir scale, the watershed scale and water users scale, and the transboundary scale. Depending on the assessment objective and context the scales are defined. To assist in this process, decision making tools guiding the process may be employed. Examples include multi factor analysis, SWOT, surveys, etc.

Based on the prior decisions taken, the elements of the assessment are being defined. As part of undertaking any assessment, it is important to identify and document the elements of a system or portfolio that may be vulnerable to the impacts of climate-related hazards.

This process should be holistic and systematic to ensure critical elements are not mistakenly excluded from the assessment. Of course, the final elements of a particular risk assessment will differ depending on the scale, intended, or provided service, geographic context and assets owned, operated and/or managed that are of interest. For example, at a municipal level, one could envision aligning these elements under assessment with the services provided to residents across the municipality as well as other elements that are particularly important for providing a continued level of service under climate change and extreme weather events.

Table 1 describes categories of elements that may be assessed. Risk assessment managers and facilitators are encouraged to review and identify together with stakeholders those categories that may be particularly relevant based on the objective of assessment, and the local geographic contexts.

Table 1: Type of elements that can be subject to assessment

This task is used to establish the climate parameters or hazards relevant for the infrastructure elements defined. Selecting climate parameters of measurable climate conditions, such as temperature, precipitation, and wind are a starting point for the definition of climate indicators. Though first a kind of exposure analysis needs to be conducted following the question: Does a particular element of the infrastructure feels a specific climate event?

At this stage of assessment, it is sufficient to understand the climate parameter relevant for the assessment. Later, when infrastructure thresholds are established (following tasks), the corresponding climate indicators can be defined (task 4).

Selection of relevant climate parameters

Those climate parameters are to be selected that are most common in the geographic area of concern and that is associated with the potential malfunction, failure of its structure or serviceability (Examples of combination events include rain, high temperature coupled with high humidity, etc.).

• When it comes to infrastructure services, one must consider the hydrological regime and what a change in river flow can impact these services. An increase in reduction of discharge can impact hydropower production, water supply for irrigation/municipal or industrial use, flood protection and e-flow dynamics.
• When it comes to the structural integrity one must specifically consider extreme climate events, such as for temperature and precipitation.

Table 2 shows an example of climate parameters.

Table 2: Example of climate parameters and hazards to be selected

Not all infrastructure elements usually interact with a types of climate parameters. The risk matrix provides an opportunity to flesh out which of the elements listed previously would “potentially” feel the hazard. For example, does monitoring equipment “feel” lightning? Does the reservoir “feel” rain? Does underground infrastructure “feel” wind? If there is no potentially connectiveness between an element and a particular climate hazard, then there is no need to further do likelihood, impact and risk analysis for that element.

Figure 12: Exposure analysis using the risk matrix

It is important to note down in the risk matrix using a Yes / no analysis. With this first order screening those elements are considered for further analysis that are deemed to be exposed to a given hazard.

Depending on the infrastructure being assessed, the services it provides, and the set objective of assessment one can define one or multiple types of impacts to be assessed. For hydropower, e-flow as well as water supply the aim is to ensure continuous provision of the service without reduction of hydropower generation or water supply. Hence the criterion can be defined as “reduction of produced power” and the “amount of time of reduction”. For the flood control service, the degree of the “hazard” (flood) created due to a certain water level as well as the degree of “exposure” of the population upstream and downstream of the infrastructure are relevant. For “structural integrity”, the “load exceedance” due to a climate or hydrological pressure, as well as “increased maintenance and operational costs” is in focus of the assessment.

Though, there is a close relationship between structural integrity and service reliability, climate risks and impacts can be assessed solely for service reliability if the focus is on anticipated changes of water amounts relevant for the service. Structural integrity assessments focus more on extreme events that could pose a threat to the entire infrastructure system. Box 5 describes the impact criteria for all types of services and structural integrity of the infrastructure.

The criteria developed in task 2 need to be transformed into measurable impact severity units for the risk assessment. The corresponding impact severity scale should extend from the maximum credible to the lowest impact of concern. The scale may have a numeric scale e.g., 1 – 5, as defined by the PIEVC matrix.

The scale is characterized through different classes of impact severity, that need to be established by the definition of impact thresholds that are connected to the degree of sensitivity of the service beneficiary system to suffer harm or impact from the climate event types selected. Defining those thresholds are based on sensitivity / vulnerability considerations (example: crop water demand threshold, minimum power generation requirement depending on economic and human needs etc.).

The impact thresholds can be generic, such as the defined number of days with service reduction or percentage of reduction compared to a key demand. Where to set these thresholds for developing a scale from 1 – 5 requires some effort, as these thresholds must be linked with meaningful impacts resulting from sensitivities. The more information on sensitivity (e.g., capability to live with power shortage) is provided the more specific they can be defined. 

For parametrization, when the duration of service reduction is considered one can either take continuous days or average days per time-period into account. In the following some specific considerations for the different services and structural elements of infrastructure are described.

• Hydropower: Water demand for producing electricity via a power plant which is located on or near a water source. The function of the power plant is converting the energy from potential energy (water flow – change in water elevation) to electrical energy. The greater the water flow and the higher the head, the more electricity the plant can produce. Due to climate change the discharge in a river can increase or decrease, leading to a reduction in hydropower efficiency. The thresholds for defining the degree of impact severity depend on the capacity of energy users to live with power outage and the types of consequential effects.
• Irrigation: Water demand for agriculture use by applying various artificial systems of tubes, pumps, and sprays. The system is usually applied in the areas where rainfall is irregular, drought events or arid climate regions. A reduction in water supply for irrigation can lead to loss of crops (food insecurity) and unemployment. The thresholds for defining the degree of impact severity can depend on the crop water requirement, the time of year or merely on the percentage of reduction of supply with regards to the demand.
• Municipal/Industrial Water supply: Municipal water demand includes water for drinking, cooking, washing, laundering, and other household functions. Industrial demand includes water for stores, offices, and manufacturing plants. A disruption or reduction in water supply can lead to a decrease in quality of life as and economic deterioration. The thresholds for defining the degree of impact severity can depend on the degree of reliance citizens have on water, the reduction that certain industries can sustain or simply a percentage of reduction with regards to the demand.
• Flood management: Governance bodies introduce flood policies and managements plans to mitigate and adapt the flood periods. Dams can store higher river discharges to protect the downstream catchments from flood. Increased floods caused by climate change could require higher dam storage capacity or an optimization of reservoir operation plans. The thresholds for defining the degree of impact severity depend on the exposure of upstream and downstream flood plains. Different definitions of exposure can come into play such as: population density, investment projects.
• Low flows: A minimum monthly average flow is required to sustain river ecosystems and continuity of navigation. Changing river flow dynamics can affect ecosystems and navigation negatively. The thresholds for defining the degree of impact severity depends on the available ecosystems and navigation requirements.
• Structural integrity: The thresholds for defining the degree of impact severity depend on the structural configuration of the infrastructure, e.g., their age, materials used, maintenance is executed, operations are implemented etc. for planned infrastructure feasibility studies and codes and standards provide an insight into impact thresholds, such as design standards.

Examples of impact thresholds and the impact scoring for different services of the six case studies is presented in the following Table 3

Watch out!!! The definition of the thresholds (percentages) presented in the table are examples only. Each project should review this table to confirm the values and revise as necessary, based on the risk appetite of key stakeholders.

Table 3: Examples of impact thresholds based on vulnerability considerations for type of assessment objective (service reliability and structural integrity)

*Evaluation depends on the available energy sources that can cover the demand

**with regards to the target power

*** growing stages of crops and soil characteristics are not considered in the evaluation

After having established the impact thresholds for the different scales of severity, task 3 dedicates to defining the corresponding climate or/and hydrological conditions, such as magnitudes of flows, that result in the defined impact for each impact severity class illustrated above.

For example:

• What is the climate indicator that would impact the structure of the asset in focus of assessment in a moderate way, defined in table 3 as the “damage rate to asset requiring 6-25% of annual maintenance budget for repairs”?
• What is the climate indicator that would impact hydro power generation reliability of the asset in focus of assessment in a moderate way, defined in table 3 as “<30% reduction** in generated power for >90 days/year or 30-70% reduction for 30-90 days/year or >70% reduction for up to 30 days/year”?

Table 4 shows flow indicators for extreme impacts, such as overtopping the dam, spillway failure or flood control. These standard structural design thresholds and indicators need to be aligned with the impact class definition illustrated in Table 3. Probable Maximum Flood, safety check flood and design flood are those performance thresholds that a Multi-Purpose Dam System is usually prepared for. Their exceedance would certainly be associated with the impact class “severe”. Climate change can modify flow conditions and their frequency of occurrence implying the need for structural adjustments.

Table 4 Standard structural design thresholds and indicators

Table 5 Service reliability thresholds and indicators

To arrive at an understanding of impactful climate and hydrological events and to define impact severity levels corresponds, understanding the load capacity of the elements under assessment is critical that may be based upon codes of practice, design standards, forensic history (past impacts to the infrastructure), constructed design values, rules of thumb, engineering guidelines, operational and maintenance standards, or factual procedures of existing infrastructures in operation, professional judgement and experience, or other relevant information.

Also, forensic analysis of the impacts experienced from past critical climate events is a valuable source of information. Especially, when conducting risk assessments of existing infrastructure, the type of load that revealed a specific damage or service loss might be different from design loads, due to aging of structural components and the way how operations and maintenance had been executed in the past.

Hence, sufficient time should be allocated for data collection. Often data are not publicly available, the buy-in from authorities needs to be established through active stakeholder involvement throughout the assessment process.

• Sector specific and public authorities often own considerable data on the infrastructure or the system in focus of assessment. These can include feasibility reports, design standards, Environmental Impact Assessments (EIA), watershed / catchment management plans. But also, data from infrastructure operators that are an important source of data, including incident records, operational rules, bathymetric surveys of the reservoir, inflow-outflow records.
• Local knowledge filtered through the overall expertise of the assessment team can help compensate for data gaps and provide a solid basis for professional judgment. Local knowledge can provide insight about the nature of previous climatic events, their overall impact in the region and approaches used to address concerns. In addition, where possible, traditional knowledge, the collective knowledge of traditions used by Indigenous groups to sustain and adapt themselves to their environment over time, should be considered based on the objectives of the assessment.
• Often, local knowledge is gained through site visits to inspect and become familiar with the elements being assessed. These visits offer the opportunity to view facilities and pose questions to local maintenance, operations, and management staff, who can offer insight on the effects of events and remedial actions that may not have been fully captured in incident reports.  While not every risk assessment may offer the opportunity to conduct site visits, it is important to gather as much local knowledge as possible through meetings and other consultations. Interviews and reviewing site photography are other approaches that can be employed in addition to or in replacement of a site visit.

Be sure to provide robust justification or rationale where possible for the chosen impact threshold. With this information the corresponding climate indicator needs to be defined.

Table 7 Examples of climate event types and corresponding criteria for which thresholds need to be defined

The following indicators provide examples, and indicate a specification that depends on the infrastructure element, component, assessment objectives to be looked at:

• Annual total wet days precipitation
• Number of days when daily precipitation exceeds 20 mm
• Largest total amount of rain that falls over a period of 5 consecutive days in a year
• Design precipitation (100 year – 24-hour duration)
• Maximum number of consecutive dry days (when precipitation is less 1.0 mm)
• Standard Precipitation and Evapotranspiration index (Characterization of wet / dry day periods over a 24-months timescale)
• 50-year (@10m) return level of annual maximum wind speed
• Lightning, Average number of strikes per year in grid relevant to watershed
• Consecutive wet days
• Very hot days (+30°C)
• Heat waves as number of hot days where maximum temperature is > 90th percentile)

The assessment team should select the boundaries and time horizons for assessment within the study. Typically, the time horizons for assessment are chosen to align with the design life / expected lifecycle of the infrastructure, or period-of-time before a planned retrofit or reassessment of climate impacts. When applying the risk assessment, the team should use:

• a climate baseline (last 30 years of relevant climate hazard information or 1981 – 2010 normal period). For the assessment of existing projects, the baseline would typically be the climate conditions on which the design was based, or which were prevailing during the period of recent operation. For the assessment of new projects, the baseline represents the climate conditions for which the initial design is made. In many cases, the baseline would be the hydro-meteorological conditions of the most current 30-year period. though, depending on the region and specific location, it has been common practice to base the design of projects in data sparse regions on data for the period 1961-1990, since for this period data of reasonable quality is typically available. This bares a significant risk that the design is inappropriate for the climate and inflow conditions expected for the first 20-30 years of operation, which is typically the period considered in evaluation of economic project performance (e.g. 2021-2050). If there is high confidence in a past trend, it may be reasonable to establish, as a baseline, a 30-year climate trace which is identical to the historical pattern, except with an adjustment  to the trending climate variable to better represent current or near-future conditions (e.g. a 30-year climate trace with increased mean daily temperature within the range that might be extrapolated  throughout the anticipated lifetime of the project  using the current or projected temperature trend). More advisory on collecting historical data can be found here.
• at least one future climate projection period for comparison. Several future periods might apply depending on the elements subject to assessment and their defined lifecycle. It is important to consider at least the full range of the current ensemble of climate projections, but care must be taken not to draw unjustifiable confidence around the full bounds of the uncertainty space. The GCM ensemble does not delimit the full universe of possible future climate change. For example, consider using the 10th, 50th and 90th percentile change values (e.g., a reduction in precipitation) from the full range of the latest models (i.e., all CMIP6 models used in the latest IPCC Assessment Report) to achieve a defensible range of plausible future change. Recompute the statistics of key climate stressors both historical and future.

Any projected values are compared directly to the values established in the baseline to understand how likelihoods of hazards (individual or combined) are projected to change with respect to current frequency or intensity.

Infrastructure-specific timeframes may also be considered depending on the assessment object and availability and complexity to obtain or develop them. Selection of time horizons should be done in tandem with the risk assessment and engineering teams.

Defining the timeframes of an assessment involves aligning the expected lifecycle of the elements with climate projections and any data used to evaluate risk. Some suggested lifecycles for infrastructure elements are listed in the Table above to the right as a starting point for an assessment. A more detailed analysis of infrastructure lifecycle is recommended as many factors affect lifecycle. The potential for infrastructure being repurposed, extending lifecycles beyond originally planned timeframes, should always be considered.

Ecosystem Based Adaptation considerations

For ecosystems the baseline differs from grey infrastructure: When Ecosystem based Adaptation (EbA) interventions are utilized, deterioration timelines for natural assets will likely differ from those for built/grey infrastructure. For example, a constructed side channel may have a longer projected lifespan than a dam. This longevity of natural assets compared to build/grey assets is one of the attractive features of EbA – it can often rely on “free” natural processes for maintenance over time. However, not all EbAs will achieve total independence, or they may require many years to do so (ADB 2019). The side channel may need to be regularly dredged to maintain service provision.

Next to assessing structural design performance under climate change, service reliability assessment is an important objective. This involves assessment of effects of climate change on the demand and supply for the infrastructure service. The changes in climate parameters are converted into basic scheme parameters (flow series, flood flows and return periods, evaporation, sediment loads, slope stability etc.). To assess the generation and performance of for example a hydropower project under conditions of climate change, a hydrological model is used to generate future inflows. The flow simulated by hydrological models can be used for service reliability assessments (hydropower, irrigation, etc.) using decision support tools.

See Figure 15 for the illustration of a flow of coupling models to simulate inflow data, system simulation (hydropower, water supply) data and economic figures. The inflow data from the hydrological model provides the input for the system simulation model which typically includes models that capture reservoir, plant operation, and other parameters such as environmental flow, restrictions and data on demand patterns. An example of such a model is the free nMAG model (Killingtveit, 1999, 2004). Detailed integrated impacts of potential climate change on physical hazards such as geohazard assessment may also be modelled and included. Though, depending on context different approaches towards modelling exist. They are based on the recommendations of the International Hydropower Association which also contains descriptions of some of the methods for hydrological modelling, flood estimation among others (IHA, 2019).

The simulation of the service culminates into a service reliability assessment under climate change conditions. First, the assessment should be done for the baseline and at least one scenario considered representative for the future climate conditions (e.g. centroid of current GCM ensemble such as CMIP6). The sensitivity analysis should be performed covering a possible range of changes in mean annual precipitation and temperature derived from the GCM ensemble. The sensitivity assessment will result in climate response maps or figures showing the performance (economic, targeted service, safety, structural integrity – thresholds identified in Activity 2, task 4) of the project across a wide range of possible climate states.

NBI developed an Excel tool to be used for executing the service reliability assessment based on the hydrological modelling results using the key data products presented in Table 10.

Table 10: Examples of climate data products prepared by NBI

Storm profiles need to be considered on top of the IDFs. Storm profiles with a rainfall peak at the end of an event will always produce the worst conditions. The likelihood of such a storm profile needs to be estimated and considered in combination with the selected return period of the rainfall intensity. This is relevant to obtain the overall probability of occurrence of the event. Observed historical timeseries of rainfall in the region can be used to extract storm profiles and determine the prevalent profile for the catchment. After generating different storm profiles, the profiles can be imported to a rainfall runoff model, where they can be used to run the model for the chosen catchment and thereby simulate the flow in the river. Obtaining the run-off / discharge that forms as a result of these rainfall events can be required for many analyses including the planning and operation of new infrastructures on the river or to facilitate the management of water resources.

The result of the hydrological model from Activity 3, Task 3 provides computed likelihoods by constructing all possible states (e.g., based on different climate ensembles) and constructing probabilities of different thresholds for different climate variables (e.g., probability of occurrence of a flood of a given magnitude), or probabilities of changing return periods by design parameters.

For the risk assessment process, the probabilities are converted to a numeric scale e.g., 1-5. The definition of these probability or likelihood metrics needs to be selected to be as unambiguous as possible. If numerical guides are used to define different probabilities, then units should be given. The probability scale needs to span the range relevant to the study in hand, remembering that the lowest probability must be acceptable for the highest defined impact, otherwise, when it comes to risk evaluation all activities with the highest impacts are defined as intolerable. For water infrastructure the Probable Maximum Flood (PMF) is such as case.

The relevant approaches to estimate likelihood / probability that can be followed individually or jointly are:

• The use of climate data (historical data and projections) and hence be able to compute the probability of occurrence of critical climate events in the future.
• The use of expert opinion that should be draw upon all relevant available information including historical, system-specific, organizational-specific, experimental, design, etc.

 Figure 19 Separate scoring scales for baseline and future climate

The scoring of likelihood is a process of translating the scientific findings of current and future climate into a score that is applicable to be used for calculating and evaluating overall risk. In some cases, to avoid biasing the scoring process with a conflation between changes in likelihood and impact, it is appropriate to withhold climate likelihood scores until the impact scoring is complete. Whether the two processes are completed separately before joining the results is a decision to be made by the project team.

There are some key considerations for the likelihood scoring process that should be factored into each analysis. These key considerations are:

• Scoring is an iterative process, where hazard indicator definitions (based on impact thresholds) and likelihood scores are developed by the climate specialist and reviewed with the project team. Time for revisions and consultation should be considered in the risk assessment process.
• Hazards should not only include historically occurring hazards, but ones that could potentially manifest under future climate change. For example, if a region has never experienced maximum temperatures over 40°C historically but could within the assessment time horizons, this hazard should be included in analysis.
• Some hazards may require multiple indicators/thresholds as impact (surpassing thresholds) is not always proportional to event likelihood of occurrence.
• Estimates of likelihood are sometimes based on climate parameters that are not perfect matches for the ones of interest by the project team. This is possible as likelihood scores represent a wide range of likelihoods within each "bin”.

The example below illustrates examples of likelihood scores for different climate indicators developed and different time scales of projections. The likelihood scores are then transferred into the risk matrix.

Table 10: Examples of likelihood scoring for different climate indicators and elements under assessment

An example of how likelihood is scored for historical and future discharge is presented in Box 7. Preferably the expert will be able to simulate as many years as possible. The projected discharge from the hydrological model can be used to derive the occurrence of impactful events with a certain severity score level defined in Activity 2, Task 3 and 4. Depending on the number of simulated years and the number of occurred events, the likelihood of occurrence can be calculated in percentage and applied to the scoring system.

For each interaction between an infrastructure element and a climate event type score the Impact Severity based on the scoring system developed (see example from Table 3).

Often the impact severity scored is built upon a substantive and controversial discussion amongst stakeholders. When consensus has been built a thorough documentation of the arguments put forward for having arrived at a specific score is necessary. 

Documentation of the selected impact scores for each element will assist in understanding the risk scores as well as assist in developing recommendations later in the assessment. Comments may describe effects, measurable outcomes (e.g., how it affects the operational goal, duration of outage, safety, critical infrastructure loss, financial, environmental effect, reputation, etc.). Organizations may choose other scales based on their project objectives. It is important the results of the scoring of severity of impact need to be reasoned well, if not even scientifically grounded. Once, in a stakeholder workshop the impact severity is scored the accompanying discussion needs to be well documented to ensure collective liability for the final risk scores developed.

Finally, the impact severity scores are transferred to the risk matrix.

Calculate the Risk (R) for each interaction Risk (R) = Exposure (E) x Impact (I) x Likelihood (L), where (E) is either yes=1 or No=0

The results are documented in the risk matrix. Now the risk matrix is completed.

Figure 20 Example matrix of the PIEVC methodology for the Borenga dam a single asset type of risk assessment (components were more than in this shortened representation

Summarize and classify risk using the scales provided. Assessors may adjust the classification categories as appropriate to align with the infrastructure owner’s risk appetite. The resulting risk calculation shows whether a given risk is high, medium, low. This involves establishing the risk levels based on probabilities of occurrence of a given undesirable event and the impacts experienced should such an event occur. This also includes the assessment of the widest possible range of potential impacts, including low-probability outcomes with large impacts. The risk levels assigned to the cells will depend on the definitions for the probability/impact scales. These can be defined by the stakeholders.

Stakeholders will determine the level of risk they are willing to bare. This level of risk may be linked to key project thresholds which should not be exceeded. Some of these may be technical and economic/financial thresholds relating to infrastructure in addition to other socio-economic and environmental criteria. The project objectives and excepted performance metrics should already provide a good basis for establishing the necessary thresholds. The level of risk would inform whether further study is required to manage the risk.

• Discuss the evaluated risk
  • Consider other factors that may be used to classify risk into priorities.
  • Consider timing, cost, available resources, finance, legal, O&M, risk tolerance, etc.
• Identify and discuss special case risks
  • Low Likelihood – High Impact that could represent significant concerns, despite low risk assessment scores.
  • High Likelihood – Low Impact that could represent significant concerns, despite low risk assessment scores.
• Based on the prioritization, identify:
  • Interactions that require no action currently (Low Risk).
  • Interactions that may require further attention, study over time (Medium Risk).
  • Interactions that require immediate action (High Risk).
  • Special case risks.
• Prepare a Concluding Statement that identifies:
  • The overall level of confidence in the assessment based on the level of detail.
  • Context regarding the level of assessment and application of findings.
  • The amount of vulnerability or resiliency of the system.
  • The global limitations of the assessment.
  • The time horizon of the assessment.
  • Climate trends that contribute to the vulnerability of the system.

• Develop recommendations for identified risks.
  • Provide justification for each recommendation.
  • Incorporate, as much as possible, organization risk tolerance and acceptable residual risk.
• Categorize the recommendations according to for example:
  • Policy/procedural changes.
  • Remedial actions.
  • Further study or analysis.
  • More comprehensive risk assessment (e.g., using the full PIEVC Protocol).
  • Engineering design considerations to engineering analysis, preliminary
  • design criteria or design changes.
  • Risk avoidance strategies.
  • Consider stopping activities in high-risk areas.
  • Other, as appropriate.
• Discuss next steps and the frequency and nature of monitoring and review of risks.

• Prepare a Statement of Assumptions and Limitations
• What was and was not considered?
• Which timeframes were considered?
• Which RCPs or future scenarios were used?
• Comment on missing, unavailable data and uncertainty.
• Comment on steps taken to address missing or unavailable data.