Section 333.06. Dam hazard ratings.

 

(1)  A hazard rating of low, significant or high for all existing and proposed dams shall be determined in accordance with the following criteria:

(a) Low hazard. A low hazard rating shall be assigned to those dams that have no development unrelated to allowable open space use in the hydraulic shadow where the failure or mis-operation of the dam would result in no probable loss of human life, low economic losses (losses are principally limited to the owners property), low environmental damage, no significant disruption of lifeline facilities, and have land use controls in place to restrict future development in the hydraulic shadow.

(b) Significant hazard. A significant hazard rating shall be assigned to those dams that have no existing development in the hydraulic shadow that would be inundated to a depth greater than 2 feet and have land use controls in place to restrict future development in the hydraulic shadow. Potential for loss of human life during failure must be unlikely. Failure or mis-operation of the dam would result in no probable loss of human life but can cause economic loss, environmental damage, or disruption of lifeline facilities.

(c) High hazard. A high hazard rating shall be assigned to those dams that have existing development in the hydraulic shadow that will be inundated to a depth greater than 2 feet or do not have land use controls in place to restrict future development in the hydraulic shadow. This rating must be assigned if loss of human life during failure or mis-operation of the dam is probable.

(2)  The owner of a dam may request that the department change the hazard rating of an existing or proposed dam by submitting adequate information which demonstrates that the land use and land use controls downstream from the dam meet the requirements for a different hazard rating. The department shall advise the owner of its action on the requested change within 90 business days after receiving the request.

History: Cr. Register, May, 1995, No. 353 , eff. 6-1-85; CR 00-136 : r. and recr., Register July 2001, No. 547 eff. 8-1-01.