In December 2022, Connective Cities and StEB Köln (City Drainage Services Cologne) in cooperation with United Cities and Local Governments (UCLG) organised an international dialogue event on managing storm and heavy rainwater in the City of Cologne, Germany. 41 experts from 16 cities and eight countries took part in the meeting. The participants presented ongoing projects from their respective municipalities, took the opportunity to engage in peer-to-peer consultation, exchanged ideas on how to reduce the risks of heavy rain and storm water events for residents and municipal infrastructure and discussed new project ideas. The dialogue event was the start of a year-long learning process. The aim was to further advance the topic of water-sensitive urban planning by taking advantage of the ideas and new contacts from the kick-off event.

Cologne: Dr Martin Cassel and Maria Ceylan reported that StEB Köln had benefited from a contact with a fellow from the Istanbul Policy Center-Sabanci University-Stiftung Mercator Initiative during the dialogue event in order to initiate an exchange on the topic of integrated water research. During the first expert mission to Istanbul, a delegation from StEB Cologne was given the opportunity to present its sponge city concept, among other topics, at a round table on the topic of water-conscious cities in Istanbul in April 2023. A group of experts from Istanbul visited Cologne in August 2023 for a further exchange of expertise.
Furthermore, Dr Martin Cassel also took part as an expert in the "Flood Management for Risk Informed Urban Development" learning process conducted by Connective Cities and the Global Initiative on Disaster Risk Management. He attended a meeting in Windhoek in April 2023 and participated in another session in eThekwini in November 2023. Mr Cassel was able to initiate valuable contacts for future exchanges.
Several projects on the topic of water and climate impact adaptation are currently being worked on within the StEB Cologne. One of these is a digital rain compass to raise citizens' awareness of the topic and to warn them in case of an emergency. Dr Martin Cassel emphasised that Cologne is one of the leading cities in Germany when it comes to heavy rain and flood prevention. He is very keen to share knowledge and make it accessible to other municipalities.

Zarqa: Mohammad Alzawahreh from the Jordanian City of Zarqa was able to gain important impulses from the dialogue event in Cologne. He particularly benefited from the peer-to-peer consultations and learnt about some non-conventional approaches that do not require a high degree of engineering expertise. As a representative of civil society with good contacts to the city administration, he was able to encourage further training on the topic of rain and storm water management. The City of Zarqa is currently working on creating GIS-based water and rain maps. One important concern is to reach out to and involve the citizens - for example in flood prevention, but also in the responsible use of drinking and rainwater.