Retrofitting Sustainable Drainage Systems (SUDS) in Public Buildings in the UK: a Cost Benefit Analysis Model

Oluwayemi, Oladunjoye (2021) Retrofitting Sustainable Drainage Systems (SUDS) in Public Buildings in the UK: a Cost Benefit Analysis Model. Doctoral thesis, Birmingham City University.

Oluwayemi Oladunjoye PhD Thesis.pdf - Accepted Version

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In a changing climate with an increased risk of flooding, developing a resilient and sustainable approach to flood management is paramount. The retrofit of Sustainable Drainage Systems (SuDS) has been applied successfully to properties and has proven to be a cost-effective solution to help mitigate future flooding and to deliver other benefits to properties, such as improvements in air and water quality, economic benefits, educational benefits and improved business reputation. Despite these benefits, there has been a relatively low uptake of SuDS in new developments and even less so in the opportunities for retrofitting SuDS in existing buildings. This research presents a cost-benefit appraisal of the retrofit of SuDS in three classes of existing public buildings to understand the decision-making process of SuDS retrofit, the flood perception around these properties, and significantly, the costs and the benefits accrued within a period of 10 years.

A synthesis of flood risk management and SuDS retrofit literature is used to inform the development of a conceptual cost-benefit analysis model for the retrofit of SuDS, focusing on the potential for improved flood risk mitigation in the context of individual properties. A qualitative study was carried out comprising a series of interviews/ focus group sessions with stakeholders to the properties, an analysis of documentary evidence and observations carried out on site. Presentations were made at regional Environment Agency meetings including individual visits to professionals. This informed the possibility of gaining access to the most appropriate case study sites which were able to meet up with the requirements of this research.

The findings of this research demonstrate the importance of stakeholder engagement during the decision-making process in helping to overcome many of the known challenges and the inclusion of expert(s) particularly the landscape architect to facilitate the implementation of these schemes. The Willingness-To-Pay (WTP) process was used effectively to value the tangible and intangible benefits arising from these schemes. The installation at each of the case study sites would provide net value to the client of well over £100,000 over 10 years versus the installation costs and return on investment would be achieved in less than 3 years. Having a stakeholder who is speicifcally involved in modeling the funding procedure of the scheme is essential. Community engagement is also a very important output of the research.

The findings highlight many of the apparent barriers that need to be overcome when installing retrofit schemes and demonstrate the importance of the intangible benefits derived. It is recommended that these are given full consideration at the decision-making stage and in supporting the uptake of the retrofit of SuDS.

Item Type: Thesis (Doctoral)
2 August 2021Submitted
12 August 2021Accepted
Uncontrolled Keywords: SuDS, flood risk management, cost benefit analysis
Subjects: CAH10 - engineering and technology > CAH10-01 - engineering > CAH10-01-07 - civil engineering
CAH13 - architecture, building and planning > CAH13-01 - architecture, building and planning > CAH13-01-02 - building
Divisions: Doctoral Research College > Doctoral Theses Collection
Faculty of Computing, Engineering and the Built Environment > School of Engineering and the Built Environment
Depositing User: Jaycie Carter
Date Deposited: 28 Feb 2023 09:52
Last Modified: 28 Feb 2023 09:52

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