Effective protection and careful use of water are prerequisites for preserving biological diversity and ensuring that our descendants have clean drinking water. Systematic monitoring of the water status is important in order to identify adverse changes in good time, identify causes of pollution and avoid them from the outset. Most of the time, dangers to our drinking water are not immediately recognizable. The remediation of polluted waters is only possible with great effort and takes a long time. Precaution is therefore the best way to protect water. The information cubes explain the most important sources of danger.