The author apologises that the acknowledgements were incomplete upon publication of Kramer, M. (Reference Kramer2024). The acknowledgements have been updated to include the contribution from Dr H. Cui.

Acknowledgements. M.K. would like to thank Dr D. Valero (Karlsruhe Institute of Technology, KIT) for fruitful discussions; Professor D. Bung (FH Aachen) for proofreading and sharing of data sets; Dr H. Cui for discussions related to new spillway data and the re-analysis of Killen’s (1968) data; and Dr A. Severi (Manly Hydraulics Laboratory) for sharing her images.