R 281.1305 Engineering plans and specifications.

Rule 5. (1) Engineering plans and specifications for the construction of new dams, the reconstruction of failed dams, or the enlargement of dams shall be prepared by a licensed professional engineer, be submitted to the department, be approved by the department before the commencement of construction, and include, at a minimum, all of the following: (a) A map that shows the location of the project and a topographic map of the dam site and impoundment area. Mapping shall show all of the following: (i) Maximum flood storage elevations of the impoundment. (ii) Property boundaries of the site, including flowage easements. (iii) Borrow area or areas. (iv) Ingress and egress routes. (v) Work limits. (b) Detailed design plans that show all of the following: (i) A profile along the centerline of the embankment and the spillway or spillways. (ii) Cross-sections of the dam at representative locations that show suitable detail of the upstream and downstream slopes and crest. (iii) The findings of investigations and analyses of embankment and foundation materials, including the locations of soil borings, soil boring logs, and proposed foundation treatment. (iv) Other drawings that are necessary to fully depict the project as determined by the department upon consultation with the applicant. (v) Other analyses that are necessary to document the adequacy of the design of the structure and protection of natural resources, public safety, and public trust as determined by the department upon consultation with the applicant. (c) An operation plan that describes how the streamflows will be maintained under various conditions. (d) Technical specifications related to the scope of work for the dam and appurtenant structures. Specifications shall reference nationally recognized and acceptable engineering specifications. (2) Engineering plans and specifications for the repair, alteration, removal, or abandonment of a dam, with the exception of minor alteration or repair projects, shall be prepared by a licensed professional engineer, be submitted to the department, and be approved by the department before commencement of construction. Plans and specifications for repair and alteration shall include sufficient detail and analyses for the department to determine whether the proposed activity adequately protects the structural integrity of the dam. Plans and specifications for removal and abandonment of a dam shall include sufficient detail and analyses for the department to determine whether the proposed activity adequately protects natural resources, public safety, and the public trust. (3) The hazard potential classification and spillway design flood determination of a dam site shall be determined by the department. The department may require the applicant to provide additional information for the department's use in these determinations. Spillway capacity requirements are fulfilled if the specified design flood is stored in the impoundment, attenuated in the impoundment system, or passed through the spillway. (4) When mitigation for the loss of natural resources is required for a proposed activity, plans and specifications for the mitigation may be required.