A novel sensor was developed which measures water conductivity by tracking the capacitance of two insulated probes submerged in the water under test. Unlike commercially available water conductivity sensors based on 4-terminal potentiometric methods, this sensor does not require metal to be in direct contact with water. In addition, this sensor has much higher sensitivity and lower power consumption compared to induction-based conductivity sensors. These differences make this sensor uniquely suited for use in distributed sensor networks, where resistance to corrosion and fouling, low power consumption, and reliability are necessary traits. Lastly, this sensor is a good fit for use by citizen scientists or hobbyists due to the ease of assembly and the low price of components needed to construct the device.