The levels of severity for potholes less than 750 mm (30 in.) in diameter are based on both the diameter and the depth of the pothole. If the pothole is more than 750 mm (30 in.) in diameter, the area should be determined in square feet and divided by 0.5 m² (5.5 ft²) find the equivalent number of holes. If the depth is 25 mm (1 in.) or less, the holes are considered medium-severity. If the depth is more than 25 mm (1 in.), they are considered high-severity.