1. (a) If a dam does not have adequate discharge capacity to pass the design event specified in Env-Wr 303.10, the owner shall submit a plan to the department to address the deficiency.

2. (b) The plan submitted pursuant to (a), above, shall:

   1. (1) Specify the action to be taken, per (c), below; and
   2. (2) Include the results of existing and proposed hydrologic and hydraulic analyses completed pursuant to Env-Wr 403.05 and Env-Wr 403.06, assessing the design event and discharge capacity of the structure.

3. (c) The plan shall specify which of the following actions the owner intends to pursue:

   1. (1) Increase the capacity of the dam to pass the design event with at least one foot of freeboard and without manual operations;
   2. (2) Submit a stability analysis to the department showing that the dam is safe against sliding or overturning, or other failure mode, as applicable, during the design event pursuant to Env-Wr 303.10, using the methods outlined in “Engineering Guidelines for Evaluation of Hydropower Projects” published by the Federal Energy Regulatory Commission (FERC), Chapter 3 dated 2016, and Chapter 4 dated 2006, available as noted in Appendix B;
   3. (3) Submit a stability analysis to the department showing that the dam is safe against erosion by overtopping during the design event pursuant to Env-Wr 303.10;
   4. (4) Stabilize the dam so that it is safe under the specified design event; or
   5. (5) Modify the dam so that the hazard classification is reduced and the dam passes the design event applicable to the new classification.

4. (d) The department shall approve the plan if the department determines that:

   1. (1) The proposed action will bring the dam into compliance with Env-Wr 303.10;
   2. (2) The work can be done in a way that will not endanger life or property downstream of the dam; and
   3. (3) The time frame for the work is reasonable under the circumstances, including the risk posed by the deficiency, the owner’s financial resources, and the timing of the work in relation to other uses of the impounded water.
5. (e) The department shall notify the owner in writing of its decision. If the plan submitted pursuant to (a), above, is not approved, the notice shall specify the reason(s) for denial.
6. (f) If work under the plan as approved constitutes reconstruction of the dam, the owner shall submit an application for dam reconstruction in accordance with chapter Env-Wr 400.

Source. #8414, eff 8-20-05; ss by #10510, eff 1-22-14; ss by #13980, eff 5-24-24 (formerly Env-Wr 303.12)