An apparatus and method for determining the water cut value of a multiphase fluid flowing within a pipe is provided. The device includes a sequestering structure disposed within the pipe, a transmitting device, a receiving device, and a processing device. The sequestering structure at least partially defines a sensing passage within the pipe, which passage has a gap extending substantially normal to a direction of fluid flow within the pipe. The sensing passage is oriented to sequester an amount of a liquid component of the multi-phase fluid sufficient to form a continuous liquid body extending across the gap of the sensing passage. The transmitting device is operable to transmit a signal through the liquid across the gap of the sensing passage. The receiving device is operable to receive the signal after it has traversed the liquid within the sensing passage, and create sensor data. The processing device is in communication with at least the receiving device to receive and process the sensor data to determine the water cut value of the liquid.