The role of NBS has been increasingly recognised for improving urban water management, emphasising it's contribution for climate-adapted development and sustainable urbanisation  . NBS that protect or restore the natural infiltration capacity of a watershed can increase the water supply service to various extents, improving drought protection and providing resilient water supply , although different forms of NBS  contribute in different ways to increasing stormwater infiltration. Additional sources of water may be available to replace the water supplied by NBS, such as rainwater harvesting, inter-basin transfers or desalination plants. Reliance on naturally sourced, locally available surface water and groundwater is more energy efficient and economical than desalination or water reuse for potable use , while rainwater harvesting is even more economical. Increasing the amount of green space in urban areas can secure and regulate water supplies, improving water security . However, Bhaskar et al.  reviewed the effect of urbanisation and NBS on baseflow and suggest that the confounded effects of infiltration and evapotranspiration losses, combined with the subsurface infrastructure  and geology, makes it difficult to predict the magnitude of baseflow enhancement resulting from the implementation of NBS in cities.
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report