The fact that so many rounds were dumped in Swiss lakes – Brienz being another of them – has been known about for decades, though people have asked questions about safety more recently.
Retired Swiss geologist Marcos Buser, who advised the government on this topic, wrote a research paper ten years ago warning of the dangers of the dumps.
The munitions pose two risks, he said. First, despite the fact it is underwater, there is still a risk of explosion, because in many cases “the army did not remove the fuses before dumping the munition”.
Then there’s water and soil contamination – there is a real chance that highly toxic TNT could pollute the lake water and the sediment.
The Swiss government acknowledges that factors including poor visibility, magnetic iron and individual ammunition weights “represent major challenges for environmentally friendly ammunition recovery”.
An assessment of possible recovery techniques in 2005 showed that all proposed solutions for ammunition recovery posed severe risks for the sensitive ecosystems of the lakes.
