Every rain barrel and green roof makes a difference. See our community's live impact and calculate your own 'Sponge Score'.
These numbers update live, showing what we achieve together. Your contribution is part of this story!
Every drop we catch directly helps keep Amsterdam's canals cleaner and healthier.
The sewer system in older parts of Amsterdam is like a bathtub that collects both wastewater and rainwater. During a heavy storm, this "bathtub" fills up extremely quickly. To prevent water from backing up into homes, there's an overflow valve that releases the mix directly into the canals. This is called a combined sewer overflow (CSO).
By capturing rain on our roofs and in our gardens, we slow down how fast the "bathtub" fills up. This prevents dirty overflows and helps us keep the canals alive and healthy for plants and animals.
Enter what you're doing (or plan to do) and instantly see your personal impact and hero status!