## 5 Conclusions  
SuDS and NBS are being rolled out as key way of greening urban environments, reducing a range of environmental hazards and improving community wellbeing and health. This study reflects on a case study in the north east of England, highlighting both the successes of partnership working in implementing sustainable drainage interventions, and the challenges in obtaining high quality data in urban and rural areas and retrofit scenarios. Our findings suggest:  
1. Coordinating a project with multiple drivers, stakeholders and novel technologies presents challenges, but multi-institution collaboration ensures there is the resource, capacity and buy-in required to support the deployment of SuDS.
2. There remains a need to evidence the performance and benefits of SuDS through long-term monitoring. However, the quality of wireless telecommunication services underpinning the transfer of data may limit what can be collected. Advances in novel satellite communication technologies may provide a route to obtaining high quality telemetered data in real time in rural or less-connected locations.
3. Whilst there is a growing interest in more innovative or integrated technologies in the SuDS community, we need to ensure this translates to the local communities too. Co-creating solutions, which consider how and why local residents might engage with water infrastructure practically, will lead to technical solutions that better align with community aspirations and are more likely to be accepted and maintained in the long-term.
4. The difficulties encountered in obtaining robust data to evidence the performance of SuDS at the street scale illustrates some of the reasons why evaluation of SuDS is not as extensive as researchers and practitioners would like.
5. It is likely to be more straightforward to design and deliver evaluation of SuDS in new developments or non-real world test sites, but this is unlikely to deliver a holistic understanding of how SuDS work in much of our urban environments.  
With the growing momentum behind the implementation of SuDS, it is crucial that we grow an informative evidence base on their effectiveness. We suggest there should be more studies to assess the physical and social impacts of the development of schemes in real world situations. Furthermore, we encourage research to monitor the performance of SuDS at a more granular level, such as the collection of data including the volume attenuated in real-time, or the quantity and quality of water discharged from SuDS features. This data would be useful to provide support for the implementation of such features individually, but also to enable the comparison, and optimisation, of SuDS technologies in a management train. Finally, we propose a number of principles to guide future studies which should: (i) use a collaborative approach across the full range of practitioners needed to implement SuDS and the community; (ii) develop novel techniques to ensure the real time monitoring of rainfall, runoff and flows can be captured from sewers; and (iii) combine investigations with a detailed mapping of surface and subsurface draining routes, to ensure monitoring is located in the most suitable points.  
**Author Contributions:** [PERSON] was responsible for the writing--original draft preparation, data collection and analysis, and data visualisation. [PERSON] was responsible for writing--review and editing, supervision, funding acquisition and conception. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research was part funded by the European Regional Development Fund (ERDF), with match funding from four project partners: Durham University, Durham County Council, Northumbrian Water Limited and the Environment Agency.  
**Acknowledgments:** We thank our project collaborators [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON], [PERSON] and [PERSON]; and the businesses directly involved in this project.  
**Conflicts of Interest:** The authors declare no conflict of interest.