[HISTORY: Adopted by the City Commission of the City of Royal Oak 10-10-1977
by Ord. No. 77-17. Amendments noted where applicable.]
In order to accomplish its purposes, this chapter includes methods and
provisions for:
A.
Restricting or prohibiting uses which are dangerous to
health, safety, and property due to water or erosion hazards, or which result
in damaging increases in erosion or in flood heights or velocities;
B.
Requiring that uses vulnerable to floods, including facilities
which serve such uses, be protected against flood damage at the time of initial
construction;
C.
Controlling the alteration of natural floodplains, stream
channels, and natural protective barriers, which help accommodate or channel
floodwaters;
D.
Controlling filling, grading, dredging and other development
which may increase flood damage; and
E.
Preventing or regulating the construction of flood barriers
which will unnaturally divert floodwaters or which may increase flood hazards
in other areas.
Unless specifically defined below, words or phrases used in this chapter
shall be interpreted so as to give them the meanings they have in common usage
and to give this chapter its most reasonable application:
The land in the floodplain within a community subject to a one-percent
or greater chance of flooding in any given year.
The flood having a one-percent chance of being equaled or exceeded
in any given year.
Any man-made change to improved or unimproved real estate, including
but not limited to buildings or other structures, mining, dredging, filling,
grading, paving, excavation or drilling operations located within the area
of special flood hazard.
A general and temporary condition of partial or complete inundation
of normally dry land areas from:
The official map issued by the Federal Insurance Administration where
the areas of special flood hazard have been designated Zone A.
Any floor usable for living purposes, which includes working, sleeping,
eating, cooking or recreation, or a combination thereof. A floor used only
for storage purposes is not a "habitable floor."
A structure that is transportable in one or more sections, built
on a permanent chassis, and designed to be used with or without a permanent
foundation when connected to the required utilities. It does not include recreational
vehicles or travel trailers.
A walled and roofed building or mobile home that is principally above
ground.
Any repair, reconstruction, or improvement of a structure, the cost
of which equals or exceed 50% of the market value of the structure either
before the improvement or repair is started, or, if the structure has been
damaged and is being restored, before the damage occurred. For the purposes
of this definition, "substantial improvement" is considered to occur when
the first alteration of any wall, ceiling, floor, or other structural part
of the building commences, whether or not that alteration affects the external
dimensions of the structure. The term does not, however, include either:
Any project for improvement of a structure to comply with existing state
or local health, sanitary, or safety code specifications which are solely
necessary to assure safe living conditions; or
Any alteration of a structure listed on the National Register of Historic
Places or a State Inventory of Historic Places.
For the purpose of this chapter only, the following rules shall apply:
A.
This chapter shall apply to all areas of special flood
hazard within the jurisdiction of Royal Oak.
B.
The areas of special flood hazard identified by the Federal
Insurance Administration in its Flood Hazard Boundary Map (FHBM), #03, dated
June 4, 1976, are adopted by reference and declared to be a part of this chapter.
The FHBM is on file at 211 Williams Street, Royal Oak, Michigan.
C.
No structure or land shall hereafter be constructed,
located, extended, converted, or altered without full compliance with the
terms of this chapter and other applicable regulations.
D.
This chapter is not intended to repeal, abrogate, or
impair any existing easements, covenants, or deed restrictions. However, where
this chapter and another ordinance, easement, covenant, or deed restriction
conflict or overlap, whichever imposes the more stringent restriction shall
prevail.
F.
The degree of flood protection required by this chapter
is considered reasonable for regulatory purposes and is based on scientific
and engineering considerations. Larger floods can and will occur on rare occasions.
Flood heights may be increased by man-made or natural causes. This chapter
does not imply that land outside the areas of special flood hazard or uses
permitted within such areas will be free from flooding or flood damages. This
chapter shall not create liability on the part of the City of Royal Oak, any
officer or employee thereof, or the Federal Insurance Administration, for
any flood damages that result from reliance on this chapter or any administrative
decision lawfully made thereunder.
A.
Establishment of development permit. A development permit shall be obtained before construction or development begins within any area of special flood hazard established in § 351-3B. Application for a development permit shall be made on forms furnished by the Director of Community Development and may include, but not be limited to, plans, in duplicate, drawn to scale showing the nature, location, dimensions and elevations of the area in question, existing or proposed structures, fill, storage of materials, drainage facilities and the location of the foregoing. Specifically, the following information is required:
(1)
Elevation, in relation to mean sea level, of the lowest
floor (including basement) of all structures;
(2)
Elevation in relation to mean sea level to which any
structure has been floodproofed;
(3)
Certification by a registered professional engineer or architect that the floodproofing methods for any nonresidential structure meet the floodproofing criteria in § 351-6B; and
(4)
Description of the extent to which any watercourse will
be altered or relocated as a result of proposed development.
B.
Designation of the Director of Community Development.
The Director of Community Development is hereby appointed to administer and
implement this chapter by granting or denying development permit applications
in accordance with its provisions.
C.
Duties and responsibilities of the Director of Community
Development. The duties of the Director of Community Development shall include,
but not be limited to:
(1)
Permit review. The Director of Community Development
shall:
(a)
Review all development permits to determine that the
permit requirements of this chapter have been satisfied.
(b)
Review all development permits to determine that all
necessary permits have been obtained from those federal, state or local governmental
agencies from which prior approval is required.
(c)
Review all development permits to determine if the proposed
development adversely affects the flood-carrying capacity of the area of special
flood hazard. For the purposes of this chapter, "adversely affects" means
damage to adjacent properties because of rises in flood stages attributed
to physical changes of the channel and the adjacent overbank areas.
[1]
If it is determined that there is no adverse effect and
the development is not a building, then the permit shall be granted without
further consideration.
[2]
If it is determined that there is an adverse effect, then technical
justification (i.e., a registered professional engineer) for the proposed
development shall be required.
[3]
If the proposed development is a building, then the provisions
of this chapter shall apply.
(2)
Use of other base flood data. When base flood elevation data has not been provided in accordance with § 351-3B, the Director of Community Development shall obtain, review and reasonably utilize any base flood elevation data available from a federal, state or other source, in order to administer § 351-6, Specific standards for flood hazard reduction.
(3)
Information to be obtained and maintained. The Director
of Community Development shall:
(a)
Obtain and record the actual elevation (in relation to
mean sea level) of the lowest habitable floor (including basement) of all
new or substantially improved structures, and whether or not the structure
contains a basement.
(c)
Maintain for public inspection all records pertaining
to the provisions of this chapter.
(4)
Alteration of watercourses. The Director of Community
Development shall:
(a)
Notify adjacent communities and the Department of Natural
Resources prior to any alteration or relocation of a watercourse and submit
evidence of such notification to the Federal Insurance Administration.
(b)
Require that maintenance is provided within the altered
or relocated portion of said watercourse so that the flood-carrying capacity
is not diminished.
(5)
Interpretation of FHBM boundaries. The Director of Community
Development shall make interpretations, where needed, as to the exact location
of the boundaries of the areas of special flood hazard (for example, where
there appears to be a conflict between a mapped boundary and actual field
conditions).
In all areas of special flood hazard, the following standards are required:
A.
Anchoring.
(1)
All new construction and substantial improvements shall
be anchored to prevent flotation, collapse, or lateral movement of the structure.
(2)
All mobile homes shall be anchored to resist flotation,
collapse, or lateral movement by providing over-the-top and frame ties to
ground anchors. Specific requirements shall be that:
(a)
Over-the-top ties be provided at each of the four corners
of the mobile home, with two additional ties per side at intermediate locations,
with mobile homes less than 50 feet long requiring one additional tie per
side;
(b)
Frame ties be provided at each corner of the home with
five additional ties per side at intermediate points, with mobile homes less
than 50 feet long requiring four additional ties per side;
(c)
All components of the anchoring system be capable of
carrying a force of 4,800 pounds; and
(d)
Any additions to the mobile home be similarly anchored.
B.
Construction materials and methods.
C.
Utilities.
(1)
All new and replacement water supply systems shall be
designed to minimize or eliminate infiltration of floodwaters into the system;
(2)
New and replacement sanitary sewage systems shall be
designed to minimize or eliminate infiltration of floodwaters into the systems
and discharge from the systems into floodwaters; and
(3)
On-site waste disposal systems shall be located to avoid
impairment to them or contamination from them during flooding.
D.
Subdivision proposals.
(1)
All subdivision proposals shall be consistent with the
need to minimize flood damage;
(2)
All subdivision proposals shall have public utilities
and facilities such as sewer, gas, electrical, and water systems located and
constructed to minimize flood damage;
(3)
All subdivision proposals shall have adequate drainage
provided to reduce exposure to flood damage; and
(4)
Base flood elevation data shall be provided for subdivision
proposals and other proposed development which contain at least 50 lots or
five acres (whichever is less).
E.
Encroachments. Any proposed development shall be analyzed to determine effects on the flood-carrying capacity of the area of special flood hazard as set forth in § 351-4C(1)(c), Permit review.
In all areas of special flood hazard where base flood elevation data has been provided as set forth in § 351-4C(2), Use of other base flood data, the following standards are required:
A.
Residential construction. New construction and substantial
improvement of any residential structure shall have the lowest floor, including
basement, elevated to or above base flood elevation.
B.
Nonresidential construction. New construction and substantial
improvement of any commercial, industrial or other nonresidential structure
shall either have the lowest floor, including basement, elevated to the level
of the base flood elevation or, together with attendant utility and sanitary
facilities, shall:
(1)
Be floodproofed so that below the base flood level the
structure is watertight with walls substantially impermeable to the passage
of water;
(2)
Have structural components capable of resisting hydrostatic
and hydrodynamic loads and effects of buoyancy; and
(3)
Be certified by a registered professional engineer or architect that the standards of this subsection are satisfied. Such certifications shall be provided to the official as set forth in § 351-4C(3)(b).
This chapter shall be known and may be cited as the "Flood Damage Prevention
Ordinance."
