Iowa Admin. Code r. 567-73.2

Current through Register Vol. 47, No. 8, October 30, 2024
Rule 567-73.2 - Definitions

"Abandonment" means to render a dam nonimpounding by dewatering and filling the reservoir created by that dam with solid materials and by diverting the natural drainage around the site.

"Acre-foot" means a volume of water that would cover one acre of land one foot deep, equal to 43,560 cubic feet of water.

"Adverse consequences" means negative impacts that may occur upstream, downstream, or at locations remote from the dam. The primary concerns are loss of human life, economic loss including but not limited to property damage, public damages, disruption of public utilities, and environmental impact.

"Appurtenant structures" means structures such as spillways, either in the dam or separate therefrom; the reservoir and its rim; low-level outlet works; and water conduits such as tunnels, pipelines, or penstocks, occurring through either the dam or its abutments.

"Auxiliary spillway" means any secondary spillway that is designed to be operated infrequently.

"Confinement feeding operation" means the same as defined in rule 567-65.1 (459,459B).

"Dam" means a barrier that impounds or stores water.

"Dam owner" means any person who owns, controls, operates, maintains, or manages a dam.

"Hazard potential" means a classification based on the possible incremental adverse consequences that result from the release of water or stored contents due to a failure or misoperation of the dam or appurtenances. The hazard potential classification of a dam does not reflect in any way on the current condition of the dam and its appurtenant structures (e.g., safety, structural integrity, or flood routing capacity).

"Height of dam" means the vertical distance from the top of the dam to the natural bed of the stream or water source measured at the downstream toe of the dam or to the lowest elevation of the outside limit of the dam if it is not across a water source.

"Incremental consequence" means the difference, under the same conditions (e.g., flood, earthquake, or other event), between the consequences that are likely to occur from the failure or misoperation of the dam and appurtenances as compared to the consequences that are likely to occur without such failure or misoperation.

"Probable" means more likely than not to occur; reasonably expected; realistic.

"Probable maximum flood" means the same as defined in rule 567-70.2 (455B,481A).

"Public damages" means as defined in rule 567-70.2 (455B,481A).

"Q100," "Q50," "Q25," "Q15," "Q10," et cetera, means the same as defined in rule 567-70.2 (455B,481A).

Iowa Admin. Code r. 567-73.2

Amended by IAB September 8, 2021/Volume XLIV, Number 5, effective 10/13/2021