France is to protect water systems from attack during the global climate summit that begins in Paris on 30 November with up to 45,000 people, including 138 heads of state, attending just over two weeks after Islamist militants struck in the French capital.
"A terrorist could very well take advantage of this gathering to strike," said Jean-Louis Fiamenghi, Head of Security for French water and waste company Veolia.
While Veolia and counter-terrorism experts made plans for the event some time ago, the 13 November attacks that killed 130 people, claimed by Islamic State militants, have put security forces on high alert.
World leaders will discuss plans to prevent global temperatures from rising more than 2 degree Celsius above pre-industrial levels at the summit, to be held at Le Bourget, north of Paris.
Veolia has installed sensors in the water network which monitor pressure, chlorine levels, temperature and conductivity - parameters that should signal if there is any contamination of the water supply.
"At this point in time, there has not been any threat of a nuclear, biological or chemical nature at any Veolia sites across France," Fiamenghi said.
Last week, French Prime Minister Manuel Valls warned of the risk of a chemical or biological attack such as the sarin gas attack in the Tokyo subway in 1995.
Veolia had, earlier, put its water sensors to use in Shanghai in 2010 during the World Expo and at the London Olympics in 2012.
