HomeMy WebLinkAbout112-97 - Ord. Amendments to the Frequently Flooded Areas Section Interim Resource Ord. 77-93 ORDINANCE NO. 112-97
AMENDMENTS TO THE FREQUENTLY FLOODED AREAS SECTION OF THE
MASON COUNTY INTERIM RESOURCE ORDINANCE NO. 77-93
IN THE MATTER OF:
AN ORDINANCE amending the following sections of the Mason County Title 17, Interim
Resource Ordinance No. 77-93-. 17.01.090, Frequently Flooded Areas and 17.01.240, Definitions;
under authority of Chapters 36.70 and 36.70A RCW; and
WHEREAS, the Mason County Board of County Commissioners adopted an Interim Resource
-for Mason County Washington, Ordinance No. 77-93, on August 2, 1993) and
WHEREAS, the Board of County Commissioners held a public hearing on August 26, 1997, to
consider the recommendation of the Mason County Planning Commission, citizens, and
Department of Community Development on amendments to the Interim Resource Ordinance to
bring it into compliance with the Growth Management Act and consistency with the
Comprehensive Plan; and
WHEREAS, the Mason County Planning Commission formulated its recommendations after a
public workshop and public hearing on May 19, 1997 and July 1, 1997, respectively; and
WHEREAS, these hearings were duly advertised public hearings; and
WHEREAS, the Mason County Board of County Commissioners reviewed the record before it
and approved Findings of Fact (see Attachment A) supporting adoption of this proposal.
NOW, THEREFORE, BE IT HEREBY ORDAINED, that the Board of County Commissioners
of Mason County hereby amends Mason County Title 17, Interim Resource Ordinance No. 77-93
to read as follows:
17.01.090 FREQUENTLY FLOODED AREAS
The purpose of this Section is to prevent the potential for further aggravation of flooding problems and to
guide development in areas vulnerable to flooding.
A. CLASSIFICATION
The following shall be classified Frequently Flooded Areas:
Frequently Flooded Areas are identified by the Federal Emergency Management Agency as those
areas within the 100 year flood"plain in a report entitled "The Flood Insurance Study for Mason
County"dated May 17, 1988,with accompanying Flood Insurance Rate Maps, and any subsequent
amendments thereto, and should be utilized as a guide to development.
The Skokomish River and floodplain as shown in the Comprehensive Flood Hazard Managemen
Plan for the Skokomish River, Februa[y 1997.
B. DESIGNATION
Lands of Mason County meeting the classification criterion for Frequently Flooded Areas are
hereby designated, under RCVV3G.7OA.OGO and RCVV3O7OA17O. anFrequently Flooded Areas
requiring immediate protection from incompatible land uses.
C. LAND USES
j[ All uses and activities within Frequently Flooded Areas are subject to the following
Development Standards.
2^ Permitted Uses in the Belfair Urban Growth Area
Hereafter all buildings,structures, or parcels of land within frequently flooded areas shall-
only be used for the following unless otherwise provided for in this ordinance.:
a_-
Agriculture and aquaculture practices:
b^ Forest practices:
C.
Outdoor recreation and parks:
d^ Single-family residential limited to 1 dwelling unit per acre.
3. The following uses within Frequently Flooded Areas are subject to conditional use permits:
aL Radio and transmission towers, resource b9sed industries, schools,trailer-mix
concrete plants,sawmills, marinas,fire stations,fuel stora-ge tanks, and
commercial outdoor recreation.
bL Other uses and activitie's determined by the Director and the Health Director that
are likely to pose a threat to public health,safety, and general welfare if located
within a freguently flooded area.
O. DEVELOPMENT STANDARDS
Development in Frequently Flooded Areas must be.in compliance with existing ordinances as
referenced to in Section 17.01.050 and shall conform to the following standards:
1^ Cluster Subdivisions
When feasible, lots shall be clustered to locate development outside of the freguentl
flooded areas.
2^ Densijy Bonuses
increased density through a Performance Subdivision as described in Title 16, Chapter
16.22. A Performance Subdivision may be used for parcels located partially within a
Subdivisions located entirely within a frequently flooded area shall not be allowed
frequently flooded area provided all allowed building areas are located outside of
frequently flooded areas.
3. Except where specific fill criteria is provided such as the Skokomish River density flood
fringe fill shall only be used if no reasonable alternative is available such as elevating on
piles, poles, or walls.
4. Skokomish River Density Flood Fringe
a. A Density Flood Fringe is hereby established for the Skokomish River and
floodplain as studied in the Comprehensive Flood Hazard Management Plan for
the Skokomish River, February 1997.A map of the Density Flood Fringe is
attached hereto as Exhibit"B" and made a part of this code by reference. All
development within the Density Flood Fringe shall comply with the following
provisions:
u Location:All new construction and substantial improvements are required
to be located on the highest existing-ground available. The Administrator,
on a case-by-case basis may allow development on areas other than the
highest existing_ground available when it can be demonstrated that such
location will not increase the flood hazards to the structure or adjacent
properties. In making a determination the Administrator shall consider the
size of the parcel, proposed access locations, proximity to other structures
and any conflicts with the setback requirements in Section 4.a(5).
All new construction and substantial improvements shall meet the general
standards presented in Section 5.1 and specific standards presented in
Sections 5.2-1 through 5.2-5 of the Flood Damage Prevention Ordinance
No. 59-91.
Maximum Allowable Density:To assure that new construction and
substantial improvements, combined with any existing development will
not cause a cumulative increase in the base flood elevation of more than
one half(0.5) foot, all such new construction and substantial
improvements shall be limited as follows:
The footprint of any use or development permitted by this chapter that will
displace floodwaters shall not exceed three (3) percent of the land area of
that portion of the lot located in the density flood fringe.
u Maximum Allowable Obstruction:The maximum width (sum of widths) of
all new construction, substantial improvements or other development shall
not exceed seventeen (17) percent of the length of the line drawn
perpendicular to the known flood water flow direction at the point where
the development(s)is located. The length of said line shall not extend
beyond the property boundary or the edge of the density flood fringe area,
whichever is less.
5) Where structures are to be constructed on adjacent parcels five (5) acres
or less in size,the building setback shall be 41.5 percent of the line drawn
perpendicular to the known flood water flow direction at the point where
the development(s) is located. For example,for two adjacent five acre
square parcels,with the flood flow perpendicular to the property lines,the
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building setback would be 193.8 feet with the maximum allowable width of
80 feet.
Setback requirements for development on parcels larger than five (5)
acres shall be evaluated on a case-by-case basis to determine
reasonable setbacks that allow for the safe conveyance of floodwaters
without increasing flood hazards or risks to surrounding properties. The
Administrator shall consider the following in making a setback
determination:
Q the proximity of the proposed structure to existing and anticipated
development;
ii the width of proposed structure perpendicular to flood water flow:
N topography of the site and surrounding area:
ev effect of proposed structure on floodwater levels in the immediate
area such as backwater effects and redirection;
(y) the existing and potential development along the cross-section
line perpendicular to flood water flow as it relates to the maximum
allowable obstruction of seventeen (17) percent.
No new footprint zones:A map of no new footprint zones,which were
delineated in the Skokomish River Comprehensive Flood Hazard
Management Plan and correspond to areas of high flood hazards, is
attached hereto as Exhibit"A" and made a part of this code by reference.
New construction shall not be allowed in these areas. Reconstruction shall
be allowed, providing that the following conditions are achieved:.
The area of the footprint of the structure following reconstruction
shall be no Greater than the areas of the footprint prior to
reconstruction.
ii Any substantial improvement of the structure shall meet the
general standards presented in Section 5.1-2 through 5.2-5 of the
Flood Damage Prevention Ordinance No. 59-91.
u Orientation:All new construction and substantial.improvements are
required to minimize the cross-sectional area perpendicular to known
floodwater flow patterns. Determination of floodwater flow direction for
such orientation shall be based upon topographical and historical flood
data on file with the administrative official. When such information is not
available, such orientation of the greatest cross-sectional area shall be in
an upstream-downstream direction at a right angle to a line drawn along
the shortest distance from the midpoint of the river channel through the
midpoint of the lot.
(� In the event development on a lot does not fully utilize the maximum
allowable lot coverage of 3%,the development rights for the remaining
area shall not be transferrable.
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17.01.20 DEFINITIONS
Additional Definitions:
Agriculture Practices: Any activity whether for commercial or recreational use directly
pertaining to production of food,fiber or livestock including but not limited to cultivation,
harvest, grazing, animal waste storage and disposal, fertilization,suppression or prevention
of diseases and insects.
Base Flood: A flood having a one percent chance of being equaled or exceeded in any
given year.
Density Flood Fringe: An alternative approach to regulating floodplain development
whereby the density of development is restricted so that when ultimate development
occurs, an insignificant increase in flood stage above that of natural conditions occurs.
Within this ordinance,the density flood fringe approach is applied to the Skokomish River
and floodplain.
Development: 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 or the
density flood fringe. (Note:This definition only applies to Section 17.01.090).
Footprint: The total area of the first floor of a structure, regardless of how the structure is
supported, or the total perimeter of any development other than a structure.
Floodplain:Any land area susceptible to the base flood.
Floodway:The channel of a river or other watercourse and the adjacent land areas that
must be reserved in order to discharge the base flood without cumulatively increasing the
water surface elevation more than one foot.
Forest Practices: Any activity conducted on or directly pertaining to forest land and related
to growing harvesting, or processing of timber including but not limited to: (1) road and trail
construction. (2) harvesting. (3) pre-commercial thinning. (4) reforestation, (5)fertilization,
(6) prevention and suppression of diseases and insects, (7) salvage of timber. (8) brush
control, and (9) slash and debris disposal.
Maximum Allowable Density: Means the percentage of the total area of any lot located in a
density flood fringe, regardless of the size of the lot,which all new development and
substantial improvements shall not exceed.
Maximum Allowable Obstruction: The maximum obstruction of a structure allowable in a
density flood fringe,to be calculated as described herein.
New Construction: Structures for which the "start of construction" commenced on or after
the effective date of this ordinance.
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No-New Footprint Zone: An area within a density flood fringe where new construction
following the effective date of this ordinance is restricted due to the occurrence of high
flood hazards Reconstruction shall be allowed contingent on conditions described herein.
Start of Construction: Includes substantial improvement, and means the date the building
permit was issued provided the actual start of construction, repair, reconstruction,
placement or other improvement was within 180 days of the permit date.The actual start
means either the first placement of permanent construction of a structure on a site, such
as the pouring of slab or footings the installation of piles the construction of columns, or
any work beyond the stage of excavation: or the placement of a manufactured home on a
foundation Permanent construction does not include land preparation,such as clearing,
grading and filling: nor does it include the installation of streets and/or walkways, nor does
it include excavation for a basement footings piers, or foundation or the erection of
temporary forms: nor does it include the installation on the property of accessory buildings,
such as garages or sheds not occupied as dwelling units or not part of the main structure.
Structure: A walled or roofed building including a gas or liquid storage tank that is
principally above ground (Note: This definition only applies to Section 17.01.090).
Substantial Damage: Damage of any origin sustained by a structure whereby the cost of
restoring the structure to its before damaged condition would equal or exceed 50 percent
of the market value of-the structure before the damage occurred.
Substantial Improvement: Any repair, reconstruction or improvement of a structure,the
cost of which equals or exceeds 50 percent of the market value of the structure either:
Before the improvement or repair is started, or
2 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 first alteration of any wall, ceiling,floor, or other
structural part of the building commences whether or not that alteration affects the
external dimension of the structure.
The term does not, however, include either:
M Any proiect 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
0 Any alteration of structures listed on the National Register of Historic Places or a
State Inventory of Historic Places.
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This Ordinance shall be in full force and effective this date.
DATED day of Se m 1997
BOARD OF COUNTY COMMISSIONERS OF
MASON COUNTY, WASFUNGTON
di, ATTEST:
Mary Jgka , Chair
Ate� 7
Cl rk of the Board
jrc ,M' e�
$olender, Commissioner ROVED AS TO FORM:
V
Cyn tiia D. Olsen, Commissioner Prosecuting Attorney
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ATTACHMENT A - ORDINANCE NO. -97
MASON COUNTY INTERIM RESOURCE ORDINANCE
FREQUENTLY FLOODED AREAS
FINDINGS OF FACT
1. Under consideration is a proposal to amend the frequently flooded critical areas protection
section of the Interim Resource Ordinance (IRO) as adopted in 1993 by Mason County.
Frequently flooded areas are protected from development because of the inherent hazards to life
and property in these areas due to flood hazards. Because of the risks associated with
development in these areas it is necessary to regulate the land uses intensity and density in order
to promote more flood compatible uses and reduce the amount of flood damages that may occur
in these areas.
2. Substantial background information on the proposed changes to the frequently flooded area
protection is contained in the memorandums and issue paper prepared by the Department of
Community Development, dated May 12, 1997 and June 9, 1997, together with their attachments
and referenced materials. The memorandums are only a small part of the process and record
which is before the commissioners and includes meetings of the Mason County Planning
Commission and the GMAC Ad Hoe Committee.
3. The proposed amendment was based on recommendations contained in an issue paper
prepared by the Department of Community Development. Further refinements to the ordinance
were made during public workshops and recorm-nendations from the Ad Hoc Committee, Planning
Commission, public and county staff. Background studies and analysis for the density flood fringe
concept were conducted by Mason County consultant, KCM, Inc. and is contained in the
Skokomish River Comprehensive Flood Hazard Management Plan, February 1997.
4. The Washington State Department of Ecology and the Federal Emergency Management
Agency recognize that a density flood fringe concept is an acceptable alternative for reducing
flood hazards in the Skokoniish River Valley. A density floodway concept is referred to in the
ordinance as a"density flood fringe" due to the fact that it will not be recognized as a"regulatory
floodway" under state or federal regulations. In addition to the density restrictions and to further
reduce development in the high hazard areas, No New Footprint Zones are designated in the
density flood fringe area. In the No New Footprint Zones, the footprint of a structure following
reconstruction shall be no greater than the area of the footprint prior to reconstruction.
5. The proposal is consistent with and balances the goals of the Growth Management Act with
.regard to frequently flooded areas by both designating and limiting development in these areas.
6. The proposal is consistent with and balances the goals and policies of the Mason County
Comprehensive Plan by providing reasonable protection of frequently flooded areas and
reasonable use of properties within these areas.
7. Special consideration was given to anadromous fish populations by limiting high density and
intensity uses within frequently flooded areas.
8. The proposal is consistent with the Flood Damage Prevention Ordinance#59-91 and the
Mason County Shoreline Master Program,
9. The proposal was presented to the GMAC Ad Hoc Committee on May 9, 1997 and at a Public
Workshop before the Planning Commission on May 19, 1997,
10. A public hearing was held on July 1, 1997 by the Mason County Planning Commission where
public comment was received on this proposed ordinance. Following the public hearing the
Planning Commission voted to forward the proposed amendments to the Board of County
Commissioners with recommendation for approval.
11. A public hearing was held on August 26, 1997 by the Mason County Board of County
Commissioners where public comments were received on this proposed ordinance.
CONCLUSIONS
From the preceding findings, it is concluded that the proposed amendments meet the intent and
purpose of the Mason County Comprehensive Plans and the Washington State Growth
Management Act and are HEREBY APPROVED.
Chair, Mason County Board of Commissioners Date
2
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EXHIBIT B*
ZONE C
DENSITY FLOOD FRINGE MAP
ZONE C R- E r\j o-T,- I 1A C I-U D ZONE C
13 Ld t P
ZONE c
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REVISED 100-YEAR
,A,till
FLOODPLAIN BOUNDARY
lF,all�O 0 1)�)
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7 LIMIT OF
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DETAILED
STUDY
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DENSITY FLOOD FRINGE BOUNDARY
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LIMIT OF STUDY
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ZONE C
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DENSITY FLOOD FRINGE BOUNDARY IS-1-1-IE EXTENT OF
THE"DETAILED STUDYI)
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