The baseline analyses currently being carried out in PolyUrbanWaters’ partner cities indicate that issues and challenges for sustainable green infrastructure development revolve not only around planning and technical questions, but above all around their green infrastructures’ sustainable management. As a result, these questions about the maintenance and further development of existing green infrastructures are increasing in importance. In this respect, the landscape of the partner cities is like many cities in South-East Asia: strongly characterized by large areas of wet rice cultivation. These green spaces are of essential importance for the hydrology of the peri-urban zones and the core city. In addition, they have an important function in maintaining a pleasant local climate. Especially during heavy rainfall, the paddy fields act as storage, buffering or delaying the release of stored water. Furthermore, as the example of the PolyUrbanWaters partner city Sam Neua/Laos shows, the loss of paddy fields is increasingly dynamic in the course of urbanisation. Without protective or compensatory measures, such as water retention basins or comprehensive drainage systems, the city’s flood vulnerability will increase due to the accelerated runoff regime, especially during heavy rainfall events. The city administration will need to counteract this with integrated stormwater management that considers the value of existing paddy fields. Ultimately, the question will be what significance paddy cultivation will have in a changed peri-urban landscape. Taking this into account, productivity gains through sustainable cultivation should enable increased value creation and thus also an increase in the economic importance of this infrastructure. Moreover, improved cultivation methods should lead to a reduction in the over-fertilization of the paddy-fields and in the resulting pollution of surface and groundwater.