Flood protection appraisals: guidance for SEPA and responsible authorities

1. Introduction

1.1. Purpose

1.1.1. The Flood Risk Management (Scotland) Act 2009 sets out a new approach to managing flood risk in Scotland. It aims to ensure that actions are focused on areas where flood risk and the benefits of investment are greatest. It sets out responsibilities and arrangements to support collaborative working for SEPA, local authorities, Scottish Water and other responsible authorities. This will ensure that long-term and nationally focused outcomes are balanced with local knowledge and priorities.

1.1.2. Decision-making at all levels of flood risk management planning should be underpinned by effective appraisal. This document provides guidance for SEPA and the responsible authorities on the economic, social and environmental aspects of options appraisal for actions promoted under the Flood Risk Management (Scotland) Act 2009. It identifies methods for identifying and assessing positive and negative impacts and recommends a decision framework, based on the principles of sustainable flood risk management (Scottish Government 2011a, 2011b) and consistent with the HM Treasury Green Book (2011) and the Scottish Government (2012) guidance on appraisal and evaluation, part of the Scottish Public Finance Manual.

1.1.3. The guidance sets out core principles which can be applied consistently across flood risk management planning to support decision-making at national, catchment and local scales. It also reflects the importance of proportionality in the level of detail of each appraisal. As such, some parts of the guidance provide an additional level of detail principally relevant to the appraisal of schemes and works.

1.1.4. The guidance is aimed at those familiar with the principles of options appraisal. It builds on historic Defra and Scottish Government guidance for flood protection schemes and recognises that it is only one part of the solution, not the complete answer. The new approach emphasises the need to consider the social and environmental impacts alongside the economic impacts.

1.1.5. The guidance is not intended to be prescriptive or to cover every possible eventuality. Appropriate specialist advice should be sought where necessary.

1.2. Aim of options appraisal

1.2.1. The aim of appraisal is to identify and assess options that achieve flood risk management objectives whilst delivering other economic, social and environmental benefits. This helps to inform the decision-making process. Options appraisal should achieve the following aims:

1.2.2. Sustainable solutions:

A sustainable solution will take full account of economic, social and environmental impacts, and protect and enhance our natural and built environment for ourselves and for future generations. The solutions must be developed with consideration of catchment processes and characteristics, making all reasonable and practical efforts to enhance the natural ability of the landscape (rural and urban) to slow and store flood water. A sustainable flood risk management action should take account of interactions between flooding mechanisms and other interventions in the catchment or in the coastal area, and should avoid as far as possible tying future generations into inflexible and expensive solutions.

1.2.3. Best use of public money:

Demands for public funding always exceed the money available. When determining how to meet the objectives for managing flood risk, it is therefore necessary to aim for economic efficiency (where the total of all forms of benefit are maximised relative to the resources used). The appraisal should not be limited to the consideration of priced benefits and resources. It should, where appropriate, also include unpriced benefits, such as the enjoyment gained from walks by a river, as well as the unpriced costs, such as degradation of landscape.

1.2.4. Accountability:

A formal process of options appraisal can demonstrate that a wide range of options has been considered, and that the advantages and disadvantages of each have been fully and transparently considered. Appraisals also create an effective audit trail of decision-making.

1.2.5. Robustness :

Robust appraisals ensure that data being used to support decision-making are appropriate for the decision being made. They recognise the assumptions, uncertainties and limitations in data and methods, and test the sensitivity of results to these uncertainties. Good quality appraisals increase certainty and confidence in the final outcome.