The European Union is developing sewer sensors for bomb sniffing purposes. As bombers have been known to dispose of their homemade explosives' ingredients down the drain, the Emphasis project hopes to establish a network of bomb-detecting sewers to sniff out these dangerous materials.
According to a BBC report, the Swedish Defense Research Agency (or FOI) is leading the charge on this bomb sniffing initiative. The EU-funded project involves electrodes being implanted into Stockholm city sewers to identify the discarded ingredients people used to make explosives. The high-tech sensors can identify extremely small amounts of these chemicals. The Swedes have built a bomb lab replica to test their results safely. They are also experimenting with bomb detection sensors on rooftops and cars in addition to sewers.