(a) The executive director shall classify all proposed and existing dams based on size (small, intermediate, or large) and downstream hazard (low, significant, or high) and not on the physical condition of the dam.(b) The executive director may reclassify the hazard classification of a dam at any time based on:(1) an inspection and downstream hazard evaluation by the executive director;(2) a report of an inspection and downstream hazard evaluation by the owner's professional engineer;(3) a breach analysis performed by either the executive director or the owner's professional engineer as described in §299.15(a)(4)(A)(i) of this title (relating to Hydrologic and Hydraulic Criteria for Dams); or(4) a review of current aerial photography and topographic maps, along with information obtained in the field.