Facts
The Feldmühle A.-G. artificial silk factory in Rorschach discharged its wastewater into two open settling ponds with an unsealed bottom from 1925 to 1938. As a result, large amounts of wastewater seeped into the permeable soil, leading to the accumulation of sulfate salts in the subsoil. These slowly reached the groundwater and made it detrimental to concrete. The contamination extended over a strip of land approximately 600 m long and 200 to 300 m wide.
At the end of 1938, the settling ponds were demolished, and the wastewater has since been discharged into the lake. However, the aftereffects of the previous seepage continued. When Max Pfister erected a new building at the harbor square in 1948, it became apparent that the sulfate-containing groundwater threatened the concrete. Pfister therefore had to take structural protective measures, incurring additional costs of CHF 18,457.55.
Pfister subsequently filed a claim against Feldmühle A.-G. for damages.
Considerations
The Federal Supreme Court ruled that the introduction of harmful substances through the groundwater flow to the plaintiff's building ground constitutes an unlawful, excessive immission within the meaning of the law of neighbors (Art. 684 ZGB). The defendant is liable for this under Art. 679 ZGB, i.e., even without fault.
The actual causal link between the previous wastewater seepage and the damage that occurred in 1948 is to be considered adequate. The defendant cannot claim that…