A flood control device and system which controls conductive fluid(s) in a conductive fluid supply line and or path, using the conductivity of said fluid(s). The conductive fluid system comprises; a conductive fluid supply line, in-line conductive fluid shut-off valve, in-line conductive fluid detector, conductive fluid sensor(s) (attached in or to conductive fluid dependent appliances), a D.C. powered central processing unit, and control panel. The conductive fluid flows through said conductive fluid line, said in-line conductive fluid shut-off valve, intern reaching said in-line conductive fluid detector which detects the flow of conductive fluid, thereby sending data to said central processing unit. When said central processing unit receives said data, said central processing unit delays for a predetermined amount of time (example 3 seconds) waiting to receive data from one or more of said conductive fluid sensor(s). If said central processing unit doesn't receive said data from said conductive fluid sensor(s) within said predetermined, said central processing unit will automatically send data to said in-line conductive fluid shut-off valve, to close, therefore terminating the forward flow of conductive fluid(s). System also includes audible signal(s) to signal an alarm condition, timing mode(s) for water conservation and monitoring in-line conductive fluid shut-off valve movements, a phone notifier for notifying user of said termination of conduct fluid due to a conductive fluid leak detection, and for (user-set) excessive water usage, means for communicating with said central processing unit by way of telephonic communication (to close or re-open said in-line conductive fluid shut-off valve), a battery back up system, and means of operating by way of manual means.