Why the bottom of Switzerland’s Lake Geneva is littered with discarded bombs and munitions

The pristine turquoise waters of Lake Geneva may appear serene, but lurking below are piles of bombs, cartridges and possibly even chemical weapons discarded decades ago.

Why the bottom of Switzerland's Lake Geneva is littered with discarded bombs and munitions
The bottom of Lake Geneva is littered with tonnes of bombs and munitions. Image: Fabrice Coffrini/AFP

Long believed to be safely slumbering beneath thick layers of protective sediment, the munitions at the bottom of the biggest lake in the Alps have raised fresh safety and environmental concerns.

“We believe there are bombs and shells, and probably rifle ammunition,” Jacques Martelain, the Geneva canton’s head geologist, told AFP.

Some also fear there might also be phosgene bombs — deadly chemical weapons — sitting on the bottom of the lake, he said.

For the first time ever, Swiss authorities will soon start mapping the piles of munitions in the lake to determine what kind of explosive debris is there, how much, and whether it should be removed.

Switzerland is a famously neutral country that did not fight in the two world wars, but its long-held position is one of well-armed neutrality.

Between World War I and the mid-1960s, thousands of tonnes of munitions, from artillery to grenades and detonators, were sunk in lakes across the nation. Following two explosions in storage depots, one of them inside a mountain, the army started to get rid of surplus post-World War II stockpiles by using underwater dumps.

Over the decades, the Swiss army is estimated to have dumped more than 8,000 tonnes of munitions in the Thun, Lucerne and Brienz lakes.

Authorities studied those stockpiles carefully and decided around a decade ago that it was safer to leave them where they were, resting at significant depths and covered with thick layers of sediment.

They estimated that there was little danger in leaving them untouched, while removing them risked shifting the sediment, releasing pollutants and causing significant damage to the aquatic ecosystem. 

Sonar tracking

However, experts have warned that the situation is different in Lake Geneva, where a private armaments company, Hispano-Suiza, dumped excess munitions right up until the 1960s.

The company, which no longer exists, had a number of arms factories in Geneva, but cantonal authorities don’t know why it used the lake as a dumping ground.

The Swiss defence ministry estimated in the early 2000s that between 150 and 1,000 tonnes of munitions had been sunk, but did not pinpoint their exact location or detail the specific weaponry. In the coming weeks, authorities will begin testing out tracking techniques in the lake, which provides Geneva with around 80 percent of its drinking water.

“We will detect these metal masses from boats using immerged sonar equipment,” Martelain said.

One of the main concerns is that the munition stocks are believed to be resting at far shallower depths than in other lakes.

The crescent-shaped freshwater lake — 73 kilometres (45 miles) long and 14 kilometres across at its widest — hits a maximum depth of 310 metres (1,017 feet) in the middle, making it the deepest lake in Switzerland.

But the munitions search will focus on the far shallower end near the city of Geneva itself, an area popular with swimmers where the lake only reaches depths of 50 to 100 metres.

Beautiful Lake Geneva is a symbol of Switzerland. Image: Fabrice Coffrini/AFP

Souvenir hunters

The Geneva authorities long thought the sediment that covered the weapons provided protection, as in other lakes. They also thought they were deeper, but in 2019 the French environmental organisation Odysseus 3.1 discovered several disembowelled ammunition crates at a depth of just 50 metres — uncovered by sediment.

Salima Moyard, a diver and former Geneva regional parliamentarian, has spent years fighting for the cantonal authorities to map the weaponry in the lake, insisting that a “complete clean-up” would be needed eventually.

She worries that amateur divers could go hunting for the weapons, a potentially risky endeavour.

“There could be individuals who go looking for the ammunition to display it on their mantlepiece,” she told AFP. “That would be really serious: serious for the people themselves, for their neighbours, for the environment.”

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Is Switzerland’s male-only mandatory military service ‘discriminatory’?

Under Swiss law, all men must serve at least one year in compulsory national service. But is this discriminatory?

Swiss military members walk across a road carrying guns
A new lawsuit seeks to challenge Switzerland's male-only military service requirement. Is this discriminatory? FABRICE COFFRINI / AFP

All men aged between the ages of 18 and 30 are required to complete compulsory military service in Switzerland. 

A lawsuit which worked its way through the Swiss courts has now ended up in the European Court of Human Rights, where the judges will decide if Switzerland’s male-only conscription requirement violates anti-discrimination rules. 

Switzerland’s NZZ newspaper wrote on Monday the case has “explosive potential” and has “what it takes to cause a tremor” to a policy which was first laid out in Switzerland’s 1848 and 1874 Federal Constitutions. 

What is Switzerland’s compulsory military service? 

Article 59 of the Federal Constitution of Switzerland says “Every man with Swiss citizenship is liable for military service. Alternative civilian service shall be provided for by law.”

Recruits must generally do 18 weeks of boot camp (longer in some cases). 

They are then required to spend several weeks in the army every year until they have completed a minimum 245 days of service.

Military service is compulsory for Swiss men aged 18 and over. Women can chose to do military service but this is rare.

What about national rather than military service? 

Introduced in 1996, this is an alternative to the army, originally intended for those who objected to military service on moral grounds. 

READ MORE: The Swiss army’s growing problem with civilian service

Service is longer there than in the army, from the age of 20 to 40. 

This must be for 340 days in total, longer than the military service requirement. 

What about foreigners and dual nationals? 

Once you become a Swiss citizen and are between the ages of 18 and 30, you can expect to be conscripted. 

READ MORE: Do naturalised Swiss citizens have to do military service?

In general, having another citizenship in addition to the Swiss one is not going to exempt you from military service in Switzerland.

However, there is one exception: the obligation to serve will be waved, provided you can show that you have fulfilled your military duties in your other home country.

If you are a Swiss (naturalised or not) who lives abroad, you are not required to serve in the military in Switzerland, though you can voluntarily enlist. 

How do Swiss people feel about military and national service? 

Generally, the obligation is viewed relatively positively, both by the general public and by those who take part in compulsory service. 

While several other European countries have gotten rid of mandatory service, a 2013 referendum which attempted to abolish conscription was rejected by 73 percent of Swiss voters. 

What is the court case and what does it say? 

Martin D. Küng, the lawyer from the Swiss canton of Bern who has driven the case through the courts, has a personal interest in its success. 

He was found unfit for service but is still required to pay an annual bill to the Swiss government, which was 1662CHF for the last year he was required to pay it. 

While the 36-year-old no longer has to pay the amount – the obligation only lasts between the ages of 18 and 30 – Küng is bring the case on principle. 

So far, Küng has had little success in the Swiss courts, with his appeal rejected by the cantonal administrative court and later by the Swiss Federal Supreme Court. 

Previous Supreme Court cases, when hearing objections to men-only military service, said that women are less suitable for conscription due to “physiological and biological differences”.

In Küng’s case, the judges avoided this justification, saying instead that the matter was a constitutional issue. 

‘No objective reason why only men have to do military service’

He has now appealed the decision to the European level. 

While men have previously tried and failed when taking their case to the Supreme Court, no Swiss man has ever brought the matter to the European Court of Human Rights. 

Küng told the NZZ that he considered the rule to be unjust and said the Supreme Court’s decision is based on political considerations. 

“I would have expected the Federal Supreme Court to have the courage to clearly state the obvious in my case and not to decide on political grounds,” Küng said. 

“There is no objective reason why only men have to do military service or pay replacement taxes. On average, women may not be as physically productive as men, but that is not a criterion for excluding them from compulsory military service. 

There are quite a few men who cannot keep up with women in terms of stamina. Gender is simply the wrong demarcation criterion for deciding on compulsory service. If so, then one would have to focus on physical performance.”

Is it likely to pass? 

Küng is optimistic that the Strasbourg court will find in his favour, pointing to a successful appeal by a German man who complained about a fire brigade tax, which was only imposed on men. 

“This question has not yet been conclusively answered by the court” Küng said. 

The impact of a decision in his favour could be considerable, with European law technically taking precedence over Swiss law.

It would set Switzerland on a collision course with the bloc, particularly given the popularity of the conscription provision. 

Küng clarified that political outcomes and repercussions don’t concern him. 

“My only concern is for a court to determine that the current regulation is legally wrong.”