(1) “Abandonment” means an affirmative act on the part of an owner to discontinue maintenance or operation of a dam.

  (2) “Administrative procedures act of 1969” means Act No. 306 of the Public Acts of 1969, being section 24.201 to 24.328 of the Michigan Compiled Laws.

  (3) “Alteration” means a change in the design of an existing dam that directly affects or may directly affect the structural integrity of a dam.

  (4) “Appurtenant works” means the structure or machinery incident to or annexed to a dam that is built to operate and maintain a dam, including spillways, either in a dam or separate from the dam; low level outlet works; and water conduits such as tunnels, pipelines, or penstocks, located either through the dam or through the abutments of the dam.

  (5) “Auxiliary spillway” means a secondary spillway which is operational at all times and does not require stoplog removal or gate manipulation.

  (6) “Dam” means an artificial barrier, including dikes, embankments, and appurtenant works, that impounds, diverts, or is designed to impound or divert water or a combination of water and any other liquid or material in the water; that is or will be when complete 6 feet or more in height; and that has or will have an impounding capacity at design flood elevation of 5 surface acres or more. Dam does not include a storage or processing tank or standpipe constructed of steel or concrete, a roadway embankment not designed to impound water, or a dug pond where there is no impoundment of water or waste materials containing water at levels above adjacent natural grade levels.

  (7) “Days” means calendar days, including Sundays and holidays.

  (8) “Design flood” means the design flow rate for spillway capacity and dam height design.

  (9) “Design flood elevation” means the maximum flood elevation that is considered in the design of the spillway capacity and freeboard for a dam.

  (10) “Downstream toe elevation” means the elevation of the lowest point of intersection between the downstream slope of an earthen embankment and the natural ground.