a. For development activities proposed to be located in a floodway, a floodway encroachment analysis that demonstrates that the encroachment of the proposed development will not cause any increase in base flood elevations; where the applicant proposes to undertake development activities that do increase base flood elevations, the applicant shall submit such analysis to FEMA as specified in Section 17-15.4 and shall submit the Conditional Letter of Map Revision, when issued by FEMA, with the site plan and construction documents.

b. For development activities proposed to be located in a riverine flood hazard area where base flood elevations are included in the Flood Insurance Study or on the FIRM but floodways have not been designated, hydrologic and hydraulic analyses that demonstrate that the cumulative effect of the proposed development, when combined with all other existing and anticipated flood hazard area encroachments, will not increase the base flood elevation more than one (1') foot at any point within the community. This requirement does not apply in isolated flood hazard areas not connected to a riverine flood hazard area or in flood hazard areas identified as Zone AO or Zone AH.

c. For alteration of a watercourse, an engineering analysis prepared in accordance with standard engineering practices that demonstrates the flood-carrying capacity of the altered or relocated portion of the watercourse will not be decreased, and certification that the altered watercourse shall be maintained in a manner which preserves the channel’s flood-carrying capacity. The applicant shall submit the analysis to FEMA as specified in Section 17-15.4. The applicant shall notify the chief executive officer of adjacent communities and the California Department of Water Resources. The Floodplain Administrator shall maintain a copy of the notification in the permit records and shall submit a copy to FEMA. (Ord. #256-2021, S2 (105-3))