We are dealing with increasingly extreme weather. Longer periods of drought alternate with large amounts of rain in a short time. The ZOHO rain letters designed by Studio Bas Sala contribute to the solution for this nuisance. They are rainwater buffer and area marking in one. The rainwater from the roof of the Hofbogen is led to the letters and thus does not enter the sewer. The smart system in the letters looks at the weather forecast via the internet. If a heavy shower is on the way, it releases its water into the surrounding garden and creates buffer capacity for the coming rain shower. During long periods of drought, it actually retains water to supply the surrounding greenery with water. The system works on solar energy. The ZOHO letters were developed and built in Rotterdam. For the production, Studio Bas Sala collaborated with, among others, Wijncoöperatie Rotterdam-Noord. This organization works with volunteers from Rotterdam North and the Schieland en Krimpenerwaard Water Board (HHSK).