Valuing high density sensing on local watercourses: reflections on extreme rainfall responses at a UK lead local flood authority

Abstract

Lead local flood authority Central Bedfordshire Council (CBC) faced an overwhelming emergency response following unprecedented rainfall (up to 148mm/day) in September 2024. In a changed climate, we can read CBC as “any lead local flood authority” and the lessons drawn from two weeks of 24-hour emergency response as widely applicable. In this paper we evaluate the response to the back-to-back storm events which occurred between 21- 29 September 2024 and delivered rainfall totalling 396% of the monthly average, overwhelming watercourses and infrastructure and flooding over 200 homes. We present the key findings from interviews with emergency responders from a range of partner organisations conducted within weeks of the emergency occurring. CBC was in the unusual position of having one highly sensored catchment, as a result of its participation in a government-funded flood innovation pilot programme. Flood risk managers’ experience of having access to this data was positive, highlighting the benefits of sensor-driven flood monitoring and prediction systems for emergency responders. Key results highlight challenges in handling public enquiries, limitations in current flood warning systems, and the potential of sensors and a streamlined flood reporting platform to enhance response efficiency. Recommendations include expanding sensor coverage and integrating a centralised public reporting framework.