19.70.625 General development standards.
A. All development proposals must comply with AMC Chapter 19.74, Floodplain Management, for general and specific flood hazard protection.
B. Development may not reduce the base flood water storage ability. Construction, grading or other regulated activities that would reduce the flood water storage ability must be mitigated by creating compensatory storage on or off site.
C. Alteration of Watercourses.
1. Projects that will relocate a watercourse must also submit a request for conditional letter of map revision, where required by FEMA. The project may not be approved unless FEMA issues the CLOMR (which requires ESA consultation) and the provisions of the letter are made part of the permit requirements.
2. The decision-maker must notify adjacent communities (if applicable) and the Department
of Ecology prior to any alteration or relocation of a watercourse, and submit evidence of such notification to FEMA.
3. Maintenance must be provided within the altered or relocated portion of said watercourse so that flood carrying capacity is not diminished. If the maintenance program does not call for cutting of native vegetation, the system must be oversized at the time of construction to compensate for said vegetation growth or any other natural factor that may need future maintenance.
D. Base flood data and flood hazard notes must be shown on the face of any recorded plat or binding site plan, including, but not limited to, base flood elevations, flood protection elevation, boundary of floodplain, and zero rise floodway.
E. All development must conform to the provisions of the currently adopted International Building Code, including submittal of a critical area report. (Ord. 3064 § 2 (Att. A), 2021)