Extensive green roof systems require little or no irrigation, however semi-intensive and intensive green roof systems require irrigation due to the plants root depths on those projects. In the instance of a drought, the system will detect low moisture content in the media and the irrigation process will begin releasing potable water or harvested rainwater. The system is also tied to the roof drain system to prevent standing water. Lastly, the roof drain inspection systems are designed to monitor the irrigation and drainage processes to make sure the water is being managed properly.