Flood protection appraisals: guidance for SEPA and responsible authorities

2. Framework for appraisal

2.1.1. This guidance document provides additional detail to support the ministerial guidance on delivering sustainable flood risk management and the policy on principles of appraisal (Scottish Government 2011a, 2011b). It is designed to:

• Provide a framework for SEPA's strategic appraisal of flood risk management actions;
• Provide the principles for options appraisal that underpin the surface water management planning process;
• Provide guidance for feasibility and design stages appraisal of actions by the responsible authorities.

2.1.2. The process of option development, refinement and selection should be carried out within a logical appraisal framework (Figure 2.1). Ideally this should include defining the purpose of the assessment, setting objectives, identifying and appraising options, and selecting the most sustainable option.

2.1.3. The appraisal process should be iterative: it should explore the problem, generate options, and progressively refine the selection. This approach applies to strategic, feasibility and design stages of appraisals to aid and guide the selection of the most sustainable option.

Figure 2.1: Summary of main stages in appraisal

2.1.4. Appraisals should use the best and most up-to-date information available, which may include SEPA's strategic flood hazard and flood risk mapping ^[1] and any further flood risk studies already carried out at the catchment or local scale. The type of information required will depend on the purpose and scale of the appraisal. Where the available information is not appropriate for the purposes of the appraisal, new information will need to be acquired.

2.1.5. Key reference material for options appraisal is listed in Box 2.1. Note that Penning-Rowsell et al. (2013) is referred to as the 'Multi-Coloured Manual' ( MCM) throughout this guidance. Reference is also made to SEPA (2015a) guidance for responsible authorities on flood hazard modelling and mapping, which underpins decision-making for flood risk management.

2.1.6. The guidance signposts to a number of other sources of information, particularly on the valuation of costs and benefits. Given the work being taken forward to implement the Flood Risk Management (Scotland) Act 2009 it is expected that the information base will continue to improve.