The CNIguard (critical national infrastructure) intrusion detection system from The Bilco Co. protects access points in drinking water distribution systems against vandalism and the threat of intentional contamination.

The watertight system uses Smart Sensing Technology to detect tampering (drilling, grinding and cutting) and can distinguish between real threats and common occurrences such as heavy rain or hail. Rated for a maximum of one false alarm per year, the system does not rely on human interpretation to determine if a threat is real.

The unit includes a controller and series of detectors mounted to access points throughout a water treatment facility. “They could be over wells. They could be access points to reservoirs, valves, pumps,” says Mike Toohey, marketing manager. “This is all done wirelessly.”

Encrypted radio signals prevent hacking. For added security, codes are changed as part of annual maintenance. The controller and detectors are powered by self-monitoring lithium batteries (18-month life). It also can be hard-wired and integrated into any type of access, including outbuildings with vertical or overhead doors.

The intrusion system was developed in the United Kingdom to guard against acts of terrorism. “In the United States, post-9/11, the government said they were going to monitor the water and if someone adds a contaminant, they were going to detect it.

“The shortcoming with that is you might prepare for 100 contaminants, and contaminant 101 gets entered into the water supply. So the United States has now come around to adapting the practice followed in the UK to protect the access points and alert the proper authorities if someone is trying to get into a vault or get a wellhead off.”

One controller can monitor up to 254 detectors and provide feedback to a SCADA system up to a mile away. “In the event someone tries to tamper with it, the units regularly buzz each other, sending signals back and forth,” Toohey says. “If a signal is sent and not received, that triggers an alarm. So it takes tampering in the field into consideration.” 800/366-6530; www.bilco.com.