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For full disclosure, I would like to point out to the editor that I'm affiliated with the same research consortium (Red&Blue) as two of the authors. Hence, the decision to not also review the revised manuscript. While affiliated, I don't work with any of the authors myself, nor is there a close relationship. So, concerns about conflicts of interest should be limited.

The manuscript evaluated the aggregated impact of a bundle of nature-based and other municipal adaptation measures on insured rain damages by comparing the insured data from two adjacent areas within the Rivierenbuurt neighbourhood, one with flood damage mitigation (FDM) measures and one without intervention. Using the statistical difference-in-difference method, the authors identified significant relations in some variables, highlighting the causal effect of FDM measures. The discussion and conclusions were valid and supported by data evidence.

The manuscript proposes a research initiative on a topic within the scope of Natural Hazards and Earth System Sciences (NHESS). I would recommend this manuscript for publication with the attached comments, particularly regarding data processing, model interpretation, and widening the discussion.

Many quantitative ex-ante studies have indicated the value of NBS interventions in urban areas, because of various Ecosystem Services, including mitigatin of urban heat island impacts, reduced impacts on the water cycle and mitigating flood risk. Especially for mitigation of flood risk many studies have indicated detailed approaches for quantification of the expected impacts.

On the other hand very few studies have been perfomed ex-post to verify the validity of the assumptions of the investments made to install NBS interventions. This study is therefore highly welcomed because the scope is exactly what the flood risk modelling community has repeatedly requested: to perform ex-post analyses to enable structured learning and inform future projects of the learnings of past projects.

However, this is also the most important limitation of the study.  I would therefore encourage the authors to expand and improve their study prior to finalizing the paper. Most importantly to include information from the ex-ante study leading to the NBS interventions: What were the expected reduction in Expected Annual Damage (EAD), how was this linked to properties of rainfall, and did the reductions in damages occur at the expected locations? Validating and/or falsifying assumptions of the ex-ante study would be a truly interesting study and probably the information is readily at hand from the documents leading to the strategy of NBS implementation. The transferability would also be improved if changed to an indicator related to EAD.

Another limitation of the study is the use of insurance data for buildings. There are always losses that are not covered by insurance and hence this should be mentioned in the discussion of the findings.

Figure 1 is difficult to interpret. I assume it is the median of the daily damages for days with more than X mm rainfall for each year? Make it more explicit and use more space to explore this data, e.g. by plotting the distributions for a suitable year and also aggregating to EAD for each catchment by year. Based on the figure alone I would assume that there would be no impacts of the NBS. This points to a more general issue with providing the readers with enough information about the data to validate the findings. More plots of both input and output data and model residuals would be an asset.

Minor points

The interventions occur in 2018 in the text but in the figure it looks like the intervention is in 2017? Is the x-asis correct?

You could consider removing 2010 from the study all together, it would make for a more robust analysis