Flood protection appraisals: guidance for SEPA and responsible authorities

3. Stage one: defining the purpose

3.1. Define the purpose

3.1.1. An appraisal should start with a clear description of the problems to be tackled. This will involve understanding existing flood risk and describing how this risk is likely to change over time.

3.1.2. Existing data and information can be used to describe the problem. Sources of data include SEPA's (national) strategic flood risk assessments, catchment and local scale flood models and maps, and local flood history. Source of models and historical flooding information are described in SEPA (2015a) flood risk modelling guidance. The data used should be fit for purpose and appropriate to the scale of the appraisal. Any significant uncertainties in the data or assumptions should be recorded.

3.1.3. All significant flood risk (economic, social and environmental) should be identified including the effects of climate change. Major constraints that may affect the choice of solution should also be stated.

3.2. Set objectives

3.2.1. One or more objectives should be set to define the purpose of the intervention. The objectives should be in line with wider government policy and plans and the HM Treasury Green Book (2011). They should be SMART (Specific, Measurable, Achievable, Relevant, Time-bound).

3.2.2. The following principles should underpin the setting of objectives:

• Main sources and impacts of flooding should be referenced;
• The baseline levels of flood risk should be included within the objectives to allow progress to be tracked;
• The objectives should be aspirational and not set limits on what is possible/ desirable. For example, it is not acceptable to state that the purpose is "to develop flood embankment with a 1% annual exceedance probability ( AEP) (1 in 100 year return period) design standard" ^[2] .

3.2.3. There should be demonstrable links between objectives set out in a flood risk management plan and their contribution to tackling national, regional or local priorities, particularly in areas identified by SEPA as being potentially vulnerable to flooding. At a project level, objectives should clearly reflect the objectives set in the relevant flood risk management plan.

3.2.4. All objectives should be established in dialogue with partners and stakeholders and should not be biased to favour or to marginalise any group.

3.2.5. When considering objectives, opportunities for delivering multiple outcomes should be considered early in the process.