A water detection device (100) may have a water sensor on both a top and bottom of the device. A water sensor circuit (1004,1006,1100, 1101) may be configured to detect water by delivering a signal may be delivered to an electrical contact (1104, 1132), and the presence of water may be determined based upon detection of the signal at the other contact (1106, 1134). The water sensor circuit device (1101) may be configured with a comparator (1116) that uses hysteresis to provide sensitivity to the presence or absence of water. In a battery-powered water sensor, the water detection signal may be delivered as an alternating signal using, e.g., a signal modulator circuit (e.g., an oscillator circuit (1114) and gate (1120) optionally coupled to a wake-sleep controller (1112)) that is coupled to a battery (133), which may avoid oxidation or other forms of ionic corrosion. In some examples, a water detection signal may be recurrently delivered to the first contact (1132) to conserve battery power.