The following provisions apply to encroachments into the regulatory floodway:
A. An encroachment in the floodway or floodplain cannot cause an increase in the base flood elevation.
B. A project in the regulatory floodway must undergo an encroachment review to determine its effect on flood flows. The encroachment analysis must include:
1. Determination and documentation that filling, grading, or construction of a structure will not obstruct flood flows and will not cause an increase in the base flood elevation upstream or adjacent to the project site;
2. Determination and documentation that grading, excavation, channel improvements, bridge and culvert replacements that remove an obstruction, do not cause increases in downstream flood flows;
3. Certification and documentation by a licensed professional engineer that the project will not result in a rise in flood heights.
C. When the proposed encroachment requires modifications to the regulatory floodway in order to avoid raising the base flood elevation, the applicants are required to obtain a conditional letter of map revision (CLOMR) from FEMA prior to issuance of a floodplain development permit. Once construction is completed the applicant must apply to FEMA for a letter of map revision for changes to the flood hazard map proposed in the CLOMR. (Ord. 3380 §7, 2010)