For all land use actions which could result in development of the Floodplain Corridor as defined by FEMA, the following is required:
A. Standards For Filling In Floodplain Corridor Lands:
1. Fill shall be designed as required by the building code, where applicable.
2. The toe of the fill shall be kept at least ten (10) feet outside of floodway channels, as defined in this chapter.
3. The amount of fill in the Floodplain Corridor shall be kept to a minimum. Fill and other material imported from off the lot that could displace floodwater shall be limited to the following:
a. Poured concrete and other materials necessary to build permitted structures on the lot.
b. Aggregate base and paving materials.
c. Plants and other landscaping material.
d. A total of fifty cubic yards of other imported fill material, or three hundred cubic yards per acre, whichever is greater. These amounts are the maximum cumulative fill that can be imported onto the site, regardless of the number of permits issued.
e. The above limits on fill shall be measured from the elevation that existed at the location as shown on the latest FEMA flood maps and shall not exceed the above amounts.
4. If additional fill is necessary beyond the permitted amounts in (3) above, then fill materials must be obtained on the lot from cutting or excavation only to the extent necessary to create an elevated site for permitted development. All additional fill material shall be obtained from the portion of the lot in the Floodplain Corridor.
5. Adequate drainage shall be provided for the stability of the fill.
6. Fill to raise elevations for a building site shall be located as close to the outside edge of the Floodplain Corridor as feasible.
7. Development of floodways is not permitted except for bridges and road crossings. Such crossings shall be designed to pass a one hundred (100) year flood without raising the upstream flood height more than six inches (6").
B. Culverting or bridging of any waterway or creek identified on the official maps adopted pursuant to Section 10-34-5 must be designed by an engineer for a one hundred year flood event. Stream crossings shall be designed to the standards currently accepted by the City Engineer and shall comply with all requirements of the City Engineer. Where no floodway has been identified, culverts must be capable of handling a one hundred (100)-year flood without any increase in the upstream flood height elevation. The engineer shall consider in the design the probability that the culvert will be blocked by debris in a severe flood and accommodate expected overflow. Fill for culverting and bridging shall be kept to the minimum necessary but is exempt from the limitations in section (A) above. Culverting or bridging of streams identified as Riparian Preservation is subject to the requirements of Section 10-34-7.
C. Non-residential structures shall be flood-proofed to one foot above the elevation flood elevation contained in the official maps adopted by Section 10-34-5 at the finished floor elevation. Where no specific elevations exist on maps, buildings shall be elevated to three feet above the stream channel on all drainage ways identified on the official maps.
D. No new residential structures are permitted in the Floodplain Corridor, except as permitted in E and F below. All residential structures shall be elevated so that the lowest habitable floor shall be raised to one foot above the elevation contained in the official maps adopted by Section 10-34-5. Where no specific elevations exist, buildings shall be elevated to three feet above the stream channel on all drainage ways identified on the official maps.
E. The elevation of the finished lowest habitable floor shall be certified to the City by an engineer or surveyor prior to issuance of a certificate of occupancy for the structure.
F. All lots modified by lot line adjustments, or new lots created from lots which contain Floodplain Corridor land must contain a building envelope on all lot(s) which contain(s) buildable area of a sufficient size to accommodate the uses permitted in the underling zone, unless the action is for open space or conservation purposes. This section shall apply even if the effect is to prohibit further division of lots that are larger than the minimum size permitted in the zoning ordinance.
G. No new habitable space shall be permitted lower than the highest floodplain corridor elevation.
H. Storage of petroleum products, pesticides, or other hazardous or toxic chemicals is not permitted in Floodplain Corridor lands.
I. Fences constructed within twenty feet (20') of any riparian area shall be limited to wire or electric fence, or similar fence that would not collect debris or obstruct flood waters, but not including wire mesh or chain link fencing.
J. Decks and structures other than buildings, if constructed on Floodplain Corridor Lands and at or below the levels specified in Paragraphs (C) and (D) of the section, shall be capable withstanding flooding and must meet FEMA standards.
K. Local streets and utility connections to developments in and adjacent to the Floodplain Corridor shall be located outside of the Floodplain Corridor, except for crossing the Corridor in the shortest possible distance. (Ord. 2019-04, 10-16-2019)