Moisture Detection Sensor Module for Soil or Water for Arduino Raspberry Pi
This sensor can be used to detect the presence of water or measure moisture levels.
Sensitivity adjustment (blue potentiometer) that can be used to set the trigger level for moisture detection. It has a green LED that shows when the trigger is on and off. When moisture is detected then the digital pin goes high (1) and when no moisture is present the digital pin is low (0).
Alternatively you can monitor the analog output to accurately measure moisture levels.