HomeMy WebLinkAbout21- Ordinance 2057 Amending Floodplain Regulations
ORDINANCE 2057
AN ORDINANCE OF THE CITY COMMISSION OF THE CITY OF BOZEMAN,
MONTANA AMENDING DIVISION 38.600. – FLOODPLAIN REGULATIONS.,
DIVISION 38.220. – APPLICATIONS AND NOTICING., SECTION 38.230.030. –
SPECIAL DEVELOPMENT PROPOSALS – ADDITIONAL APPLICATION
REQUIREMENTS., SECTION 38.410.100. - WATERCOURSE SETBACK., CHAPTER
16 – ENVIRONMENT AND HEALTH ARTICLE 2 NUISANCES, AND DIVISION
38.700. - TERMS AND INTERPRETATION TO REVISE CITY FLOODPLAIN
REGULATIONS, TO DELETE SECTION 42.02.010 – CHANNEL TO BE KEPT FREE
FROM OBSTRUCTIONS, AND SECTION 42.02.020 –NARROWING, TURNING OR
OBSTRUCTING CHANNEL PROHIBITED; EXCEPTION AND PROVIDING AN
EFFECTIVE DATE
WHEREAS, flooding may cause loss of life, damage to property, disruption of
commerce and essential governmental services, and unsanitary conditions all of which are
detrimental to the health, safety, and welfare of city occupants; and
WHEREAS, the public interest necessitates management and regulation of flood
hazards in a manner consistent with sound land and water use management practices intended to
prevent and alleviate flood hazard threats to life and health and reduce private and public economic
losses; and
WHEREAS, Division 38.600. - Floodplain Regulations of the Bozeman Municipal
Code (BMC) establishes land use regulations to promote public health, safety, and welfare; and
WHEREAS, this Ordinance 2057 complies with the Montana Floodplain and Floodway
Management Act (Title 76, Chapter 5, Montana Code Annotated) and state regulations
implemented under authority given thereby to the State of Montana Department of Natural
Resources and Conservation (DNRC) (Chapter 36.15 Administrative Rules of Montana); and
WHEREAS, DNRC has reviewed this Ordinance 2057 and found it acceptable in
meeting the minimum standards established by the State of Montana for local floodplain
regulations; and
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WHEREAS, this Ordinance 2057 complies with Title 44 Part 60.3 of the Code of
Federal Regulations promulgated by the Federal Emergency Management Agency (FEMA); and
WHEREAS, FEMA has reviewed this Ordinance 2057 and found it adequate and
consistent with the comprehensive criteria for land management and use established in 44 CFR
60.3; and
WHEREAS, FEMA has completed a new Flood Insurance Study and produced new
Flood Insurance Rate Maps that update and replace the Flood Insurance Study of Gallatin County,
Montana, and Incorporated Areas, dated September 2, 2011 (FEMA FIS No. 30031CV000A)
inclusive of the City of Bozeman; and
WHEREAS, DNRC, pursuant to BMC Sec. 76-5-201(3) MCA, has determined the
floodplains and floodways designated by FEMA under the new Flood Insurance Study and Flood
Insurance Rate Maps are in compliance with Parts 1 through 4 of the Montana Floodplain and
Floodway Management Act; and
WHEREAS, the new Flood Insurance Study and Flood Insurance Rate Maps become
effective on April 21, 2021 (FEMA Flood Insurance Study Number 30031CV001B); and
WHEREAS, the City of Bozeman must officially adopt the new Flood Insurance Study
and Flood Insurance Rate Maps by ordinance with an effective date no later than the April 21,
2021 effective date established by FEMA in order to remain a community in good standing with
the National Flood Insurance Program; and
WHEREAS, the City of Bozeman participates in the National Flood Insurance Program
as a community in current good standing; and
WHEREAS, this Ordinance 2057 is a comprehensive update to Division 38.600. –
Floodplain Regulations that existed prior to the effective date set forth herein; and
WHEREAS, any future amendments to this Ordinance 2057 must be found adequate
and acceptable by DNRC and FEMA upon their respective reviews at least thirty (30) days prior
to the effective date of any future amendments hereto; and
NOW, THEREFORE, BE IT ORDAINED by the City Commission of the City of
Bozeman, Montana, that:
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Section 1
Division 38.600. - Floodplain Regulations of the Bozeman Municipal Code be amended as
follows:
DIVISION 38.600. - FLOODPLAIN REGULATIONS [6]
Footnotes:
--- (6) ---
State Law reference— Floodplain and floodway management, MCA 76-5-101 et seq.
BMC Sec. 38.600.010. - Title.
These regulations are known and may be cited as the city floodplain regulations. This
division 38.600 is in accordance with the authority of the laws of the state exercised by the city,
and other authority as may be possessed by the city.
BMC Sec. 38.600.020. - Purpose.
A. This chapter has established regulations to prohibit development within floodplains in order
to protect public health and safety, safeguard water quality, provide for wildlife habitat and
accomplish other public purposes. However, there are certain limited circumstances where
development within the floodplain either currently exists or may be permitted from time to
time to advance a public purpose. This division 38.600 provides standards which must be met
in order to promote the public health, safety and general welfare, to minimize flood losses in
areas subject to flood hazards, and to promote wise use of the floodplain when those limited
circumstances occur. This division 38.600 has been established with the following purposes:
1. To guide development of the 100-year floodplain within the city limits consistent with
the enumerated findings by:
a. Establishing zoning regulations coincident with and applicable to those areas at risk
of flooding with special requirements and regulations to protect the public welfare;
b. Recognizing the right and need of watercourses to periodically carry more than the
normal flow of water;
c. Participating in coordinated efforts of federal, state and local management activities
for 100-year floodplains;
d. Ensuring the regulations and minimum standards adopted, insofar as possible,
balance the greatest public good with the least private injury; and
e. Carrying out the provisions of this division 38.600 in a fashion consistent with the
remainder of this chapter and the public policies set forth in the city's growth policy
consistent with the authority of title 76, chapter 5, part 3 (MCA 76-5-301 et seq.).
2. Specifically, it is the purpose of this division 38.600 to:
a. Restrict or prohibit uses that are dangerous to health, safety and property in times of
flood, or that cause increased flood heights and velocities;
b. Require that uses vulnerable to floods, including public facilities, be provided with
flood protection at the time of initial construction;
c. Identify lands unsuitable for certain development purposes because of flood hazards;
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d. Minimize the need for rescue and relief efforts associated with flooding undertaken
at the expense of the general public;
e. Ensure that potential buyers are notified that property is within a 100-year floodplain
and subject to the provisions of these regulations;
f. Ensure that those who occupy 100-year floodplains assume responsibility for their
actions; and
g. Protect water quality and persons and property located downstream.
BMC Sec. 38.600.030. - Jurisdictional area.
This division 38.600 applies to all lands within the boundaries of the city, shown on the
official floodplain maps, including any amendments or revisions, as being located within a 100-
year floodplain district or that may otherwise be identified as lying within a 100-year floodplain
through additional floodplain delineation, engineering analysis, topographic survey, or other
objective and factual basis.
BMC Sec. 38.600.040. - Floodplain regulation establishment and applicability.
These floodplain regulations are hereby established and are applicable in all areas defined by
the base flood elevations and 100-year floodplains as delineated in the flood insurance study, or
other means specified in section 38.600.030. The basis for the flood insurance study is a
scientific and engineering report entitled the "Flood Insurance Study of Gallatin County,
Montana, and Incorporated Areas," dated September 2, 2011 (FEMA FIS No. 30031CV000A),
with accompanying flood insurance rate maps and flood boundary/floodway maps. The official
floodplain maps, together with the flood insurance study are on file in the office of the city
Floodplain Administrator. The floodplain regulations are hereby established in all areas subject
to flooding. Depiction on the official zoning map of the city is not required for this district.
BMC Sec. 38.600.050. - Abrogation and greater responsibility.
It is not intended by this division 38.600 to repeal, abrogate, or impair any existing
easements, covenants, deed restrictions, or underlying zoning. However, where this division
38.600 imposes greater restrictions, the provisions of this division 38.600 prevail.
BMC Sec. 38.600.060. - Floodplain Administrator.
The city Floodplain Administrator is designated in 38.200.010. The responsibilities of this
position are outlined in 38.600.130.
BMC Sec. 38.600.070. - Regulation interpretation.
The interpretation and application of the provisions of these regulations are considered
minimum requirements and liberally construed in favor of the governing body and not deemed a
limitation or repeal of any other powers granted by state statute or self-government status.
BMC Sec. 38.600.080. - Compliance with regulations.
No structure or land use may be located, extended, converted or structurally altered without
full compliance with the provisions of this chapter, these specific regulations, and other
applicable regulations. These regulations meet or exceed the minimum floodplain development
requirements as set forth by the state department of natural resources and conservation and the
National Flood Insurance Program.
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BMC Sec. 38.600.090. - Flood hazard evaluation.
A. General. Land subject to being flooded by a flood of 100-year frequency as defined by title
76, chapter 5, Montana Code Annotated (MCA 76-5-101 et seq.), or land deemed to be subject
to flooding by the city, may not be subdivided or developed for building or residential
purposes, or other uses that may increase or aggravate flood hazards to life, health or welfare,
or that may be prohibited by state or local floodplain or floodway regulations.
B. Requirement for study.
1. If any portion of a proposed subdivision or other development is:
a. Within 1,000 horizontal feet and less than ten vertical feet of a watercourse draining
an area of 25 square miles or more; and
b. No official floodplain or floodway delineation study of the watercourse has been
made; then
c. The subdivider or other developer must provide a floodplain analysis report
establishing the calculated 100-year frequency water surface elevations and 100-year
floodplain boundaries. The analysis and report must be prepared by a licensed
professional engineer qualified in this field of work.
2. If any portion of a proposed subdivision or other development is:
a. Within 1,000 horizontal feet and less than ten vertical feet of a watercourse draining
an area less than 25 square miles; and
b. No official floodplain or floodway delineation study of the watercourse has been
made; then
c. The subdivider or other developer must:
(1) Demonstrate to the satisfaction of the city engineering department that the 100-
year peak runoff of the watercourse will not affect the subdivision; or
(2) Delineate the existing and proposed 100-year flood limits of the stream or
streams within 1,000 feet of the proposed subdivision and specify any mitigation
that may be required to protect the proposed subdivision and adjacent properties
from potential flooding and erosion damage due to any proposed changes within
the delineated flood limits.
d. The developer's professional engineer, licensed in the state, must provide written
certification to the city that the mapped flood locations and proposed mitigation must
protect against damage by the 100-year flood.
3. Submission of report. The report must be submitted at the time of preliminary plat or
plan application. The report may be submitted, upon the request of the city commission
or development review committee, to the floodplain management section, water resources
division, state department of natural resources and conservation, for review and
concurrence.
4. Contents of report. The required report must include the following information:
a. Certification. Certification of the report by a registered professional engineer.
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b. Overall plan view. An overall scaled plan view (project map) with identified scale
for vertical and horizontal distance showing the following:
(1) Watercourse;
(2) Floodplain boundaries;
(3) Location of property;
(4) Contours;
(5) Cross sections;
(6) Bridges or other constrictions in the floodplain; and
(7) USGS gauging stations (if any).
c. Benchmark. The location and elevation of a temporary benchmark established within
the subdivision and referenced to mean sea level with appropriate elevation
adjustment.
d. Cross sectional information.
(1) Cross sections must follow the applicable guidelines established by the state
department of natural resource conservation. If applicable guidelines are not
available, cross section information must be as follows:
(a) Cross section elevations and stations should be determined at points
representing significant breaks in ground slope and at changes in the
hydraulic characteristics of the floodplain (e.g., points where ground cover,
soil or rock conditions change). Elevations must be reported in NAVD88.
(b) Each cross section must cross the entire floodplain. The cross section
alignment should be perpendicular to the general flow of the watercourse,
the slope of the channel and the hydraulic characteristics of the reach. A
minimum of four cross sections are required over the entire reach with at
least two cross sections at the property where the elevations are desired.
Additional cross sections must be taken at bridges, control structures or
natural constrictions in topography.
Figure 38.600.090.
Section view of floodplain.
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(2) Photogrammetric methods may be used in lieu of cross sections whenever
appropriate and when reviewed and approved by the Floodplain Administrator.
e. Bridges. Descriptions and sketches of all bridges within the reach, showing
unobstructed waterway openings and elevations.
f. Water surface. Elevations of the water surface determined by survey as part of each
valley cross section.
g. Supporting documentation. Engineering report of computer computations,
calculations and assumptions that may include:
(1) Hydrology (research of published hydrology or calculations showing how
hydrology was derived);
(2) Input files (hard copy and on diskette or CD-ROM); and
(3) Output files (hard copy and on diskettes or CD-ROM).
C. Waiver of requirement. The Floodplain Administrator may waive this requirement where
the subdivider contacts the water resources division, state department of natural resources
and conservation, and that agency states in writing that the data indicate that the proposed
subdivision is not in the flood hazard area as defined in this division 38.600.
BMC Sec. 38.600.100. - Rules for interpretation of floodplain district boundaries.
The boundaries of the 100-year floodway must be determined by scaling distances on the
official floodplain maps and using the floodway data table contained in the flood insurance study
report. The maps may be used as a guide for determining the 100-year floodplain boundary, but
the exact location of the floodplain boundary must be determined where the base flood elevation
intersects the natural ground. The Floodplain Administrator may require an on-site survey and
staking of the floodplain boundary prior to issuance of any permit or any development
undertaken following issuance of a permit.
BMC Sec. 38.600.110. - Warning and disclaimer of liability.
This division 38.600 does not imply that areas outside the delineated floodplain boundaries
or permitted land uses will always be totally free from flooding or flood damages. These
regulations do not create a liability or cause of action against the city or any officer or employee
thereof for flood damages that may result from reliance upon these regulations.
BMC Sec. 38.600.120. - Disclosure provision.
All owners of property in an identified 100-year floodplain as indicated on the official
floodplain maps must notify potential buyers or their agents that such property is subject to the
provisions of this division 38.600.
BMC Sec. 38.600.130. - Administration of regulations.
A. As provided in section 38.200.010, the city Floodplain Administrator has been designated by
the city commission, and has the responsibility of such position as outlined in this division
38.600.
B. Section 38.410.100 has established a public policy to avoid development within floodplains,
along with certain exceptions. The administration of these regulations must be done in a
fashion consistent with both the letter and spirit of that section.
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C. The city Floodplain Administrator is appointed with the authority to review floodplain
development permit applications, proposed uses and construction to determine compliance
with these regulations. The city Floodplain Administrator is required to ensure all necessary
permits have been received from those governmental agencies from which approval is
required by federal and state law and local codes, including section 404 of the Federal Water
Pollution Control Act of 1972, 33 USC 1334, and under the provisions of the Natural
Streambed and Land Preservation Act.
1. Additional factors. Floodplain development permits will be granted or denied by the city
Floodplain Administrator on the basis of whether the proposed establishment, alteration
or substantial improvement of an artificial obstruction meets the requirements of this
division 38.600 and other requirements of this chapter. Additional factors that will be
considered for every permit application are:
a. The danger to life and property due to increased flood heights, increased floodwater
velocities or alterations in the pattern of flood flow caused by encroachments;
b. The danger that materials may be swept onto other lands or downstream to the injury
of others;
c. The proposed water supply and sanitation systems and the ability of these systems
to prevent disease, contamination and unsanitary conditions;
d. The susceptibility of the proposed facility and its contents to flood damage and the
effects of such damage on the individual owner;
e. The importance of the services provided by the facility to the community;
f. The requirement of the facility for a waterfront location;
g. The availability of alternative locations not subject to flooding for the proposed use;
h. The compatibility of the proposed use with existing development and anticipated
development in the foreseeable future;
i. The relationship of the proposed use to the growth policy and floodplain management
program for the area;
j. The safety of access to property in times of flooding or for ordinary and emergency
services; and
k. Such other factors as are in harmony with the purposes of this chapter, these
regulations, the Montana Floodplain and Floodway Management Act and the
National Flood Insurance Program.
D. A floodplain development permit application is considered to have been automatically
granted 60 days must be reviewed and acted upon within 180 working days after the date of
receipt of the complete application by the city Floodplain Administrator. Unless the applicant
has been notified that the permit is denied, conditionally approved or If additional information
pertinent to the permit review process is required the time for review must stop and restart
with submittal of the additional information. A floodplain permit must not act as a waiver or
variance from the other requirements of this chapter.
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E. The city Floodplain Administrator must adopt such administrative procedures as may be
necessary to efficiently administer the provision of these regulations.
F. The city Floodplain Administrator must maintain such files and records as may be necessary
to document nonconforming uses, base flood elevations, floodproofing and elevation
certifications, fee receipts, the issuance of permits, agenda, minutes, records of public
meetings, and any other matters related to floodplain management in the city. Such files and
records must be open for public inspection. In matters of litigation, the city attorney may
restrict access to specific records.
G. The city Floodplain Administrator may require whatever additional information is necessary
to determine whether the proposed activity meets the requirements of these regulations.
Additional information may include hydraulic calculations assessing the impact on base flood
elevations or velocities, level survey or certification by a registered land surveyor,
professional engineer or licensed architect that the requirements of these regulations are
satisfied.
H. Upon receipt of an application for a permit or a variance, the city Floodplain Administrator
must prepare a notice according to the requirements of division 38.220 of this chapter.
I. Copies of all permits granted must be sent to the state department of natural resources and
conservation in Helena, Montana.
1. In riverine situations, notifications by the city Floodplain Administrator must be made
to adjacent communities, the floodplain management section (DNRC) and FEMA prior
to any alteration or relocation of a stream. The flood-carrying capacity within the
altered or relocated portion of any stream must be maintained. Erosion control measures
must be incorporated to ensure stability of altered channels and stream banks.
BMC Sec. 38.600.140. - Permit applications.
A. Activities or uses that require the issuance of a permit, including the expansion or alteration
of such uses, may not be initiated, established or undertaken until a permit has been issued by
the city Floodplain Administrator.
B. Permit applicants must be required to furnish the following information as deemed necessary
by the city Floodplain Administrator for determining the suitability of the particular site for
the proposed use:
1. Three sets of plans drawn to scale (including dimensions) showing the nature, location
and elevation of the lot; existing and proposed structure locations; fill, storage or materials
site; floodproofing measures; mean sea level elevation of first floor of proposed
structures; and location of the channel and limits of 100-year floodplain boundary;
2. A plan view of the proposed development indicating external dimensions of structures;
street or road finished grade elevations; well locations; individual sewage treatment and
disposal sites; excavation and/or fill quantity estimates; and site plan and/or construction
plans;
3. Specifications for floodproofing, filling, excavating, grading, bank stabilization, storage
of materials and location of utilities;
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4. A professional engineer's or registered architect's design calculations and certification
that the proposed activity has been designed to be in compliance with these regulations;
5. Certification of floodproofing and/or elevation must be provided on a standard form
available from the city Floodplain Administrator; and
6. Adjoining owners. Names and addresses of record owners of lots and tracts immediately
adjoining the proposed floodplain permit.
C. To determine that the permit specifications and conditions have been completed, applicants
who have received permits must furnish the following at the time of an on-site conformance
inspection:
1. Certification by a registered professional engineer or licensed land surveyor of the actual
mean sea level elevation of the lowest floor (including basement) of all new, altered or
substantially improved buildings;
2. If floodproofing techniques were used for buildings, the mean sea level elevation to
which the floodproofing was accomplished must be certified by a structural engineer or
licensed architect in the same manner;
3. Certification is also required for artificial obstructions other than buildings, that the
activity was accomplished in accordance with these regulations and the design plans
submitted with the application for the permit activity. This certification may be waived
by the city Floodplain Administrator if it can be clearly ascertained by a site inspection
that the activity was accomplished in accordance with these regulations; and
4. Certification of floodproofing and/or elevation must be provided on a standard form
available from the city Floodplain Administrator.
BMC Sec. 38.600.150. - Emergency waiver.
A. Emergency repair and replacement of severely damaged public transportation facilities,
public water and sewer facilities, public utility electricity and natural gas distribution facilities,
and flood control works may be authorized. Floodplain development permit requirements may
be waived if:
1. Upon notification and prior to emergency repair and/or replacement, the city Floodplain
Administrator determines that an emergency condition exists warranting immediate
action; and
2. The city Floodplain Administrator agrees upon the nature and type of proposed
emergency repair and/or replacement.
B. Authorization to undertake emergency repair and replacement work may be given verbally
if the city Floodplain Administrator feels that such a written authorization would unduly
delay the emergency works. Such verbal authorization must be followed by a written
authorization describing the emergency condition, and the type of emergency work agreed
upon and stating that a verbal authorization had been previously given.
BMC Sec. 38.600.160. - Review; variances; appeals.
Appeals and variances from this division 38.600 may be taken as set forth in division 38.250
of this chapter. The city Floodplain Administrator must maintain records of the variance
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notification and actions, including justification for their issuance, and forward copies of all
variance actions to the state department of natural resources and conservation and the Federal
Emergency Management Agency.
BMC Sec. 38.600.170. - Floodplain development; compliance.
Any use, arrangement or construction not in compliance as authorized by permit, will be
deemed a violation of this division 38.600 and punishable as provided in division 38.200 of this
chapter. An applicant is required to submit certification by a registered professional engineer,
architect, land surveyor or other qualified person designated by the city Floodplain Administrator
that finished fill and lowest building floor elevations, floodproofing, hydraulic design or other
flood protection measures were accomplished in compliance with these regulations.
BMC Sec. 38.600.180. - Emergency preparedness; planning.
In formulating community development goals, the community must consider the
development of a plan for evacuating users of all development located within floodprone areas.
This plan should be developed, filed with, and approved by appropriate community emergency
management authorities.
BMC Sec. 38.600.190. - Applications; specific standards.
The minimum floodplain development standards listed in this division 38.600 apply to the
floodway and floodway fringe portions of the 100-year floodplain as delineated on the flood
hazard area maps or other flood hazard areas as may be determined by section 38.600.040.
BMC Sec. 38.600.200. - Floodway—Uses allowed without floodplain permits.
A. When a site specific exemption or relaxation of the standards of section 38.410.100 allow
utilization of a portion of the floodplain, the following uses are allowed without a permit
within the floodway, provided that such uses conform to the provisions of sections 38.600.350
through 38.600.390; are not prohibited by any other ordinance, resolution or statute; and do
not require fill, excavation, permanent storage of materials, or equipment or structures other
than portable structures:
1. Agricultural uses;
2. Accessory uses such as loading and parking areas associated with industrial and
commercial facilities;
3. Private and public recreational uses such as golf courses, driving ranges, archery ranges,
picnic grounds, boat-launching ramps, parks, wildlife management and natural areas, fish
hatcheries, fishing areas, and hiking or horseback riding trails;
4. Residential uses such as lawns, gardens, parking areas and play areas;
5. Irrigation and livestock supply wells, provided that they are located at least 500 feet from
domestic water supply wells; and
6. Fences, except permanent fences crossing channels.
BMC Sec. 38.600.210. - Floodway—Uses requiring floodplain permits.
A. When a site specific exemption or relaxation of the standards of section 38.410.100 allow
utilization of a portion of the floodplain, the following artificial obstructions may be permitted
in the floodway subject to the issuance of a permit by the city Floodplain Administrator:
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1. Excavation of material from pits and pools provided that:
a. A buffer strip of undisturbed land is left between the edge of the channel and the
edge of the excavation. This buffer strip must be of sufficient width to prevent flood
flows from channeling into the excavation;
b. The excavation meets all applicable laws and regulations of other local and state
agencies; and
c. Excavated material is disposed of or stockpiled outside the floodway;
2. Railroad, highway and street stream crossings provided the crossings are designed to
offer minimal obstruction to flood flow. Stream crossings may not increase the elevation
of the 100-year flood more than one-half foot nor cause a significant increase in flood
velocities;
3. Limited filling for highway, street and railroad embankments not associated with stream
crossings, provided that:
a. Reasonable alternate transportation routes outside the designated floodway are not
available; and
b. Such floodway encroachment is located as far from the stream channel as possible
and may not result in a cumulative increase in base flood elevations, after allowable
encroachments into the floodway fringe, exceeding one-half foot;
4. Buried or suspended utility transmission lines, provided that:
a. Suspended utility transmission lines are designed so the lowest point of the
suspended line is at least six feet higher than the base flood elevation;
b. Towers and other appurtenant structures are designed and placed to withstand and
minimally obstruct flood flows; and
c. Utility transmission lines carrying toxic or flammable materials are buried to a depth
of at least twice the calculated maximum depth of scour for a 100-year flood. The
maximum depth of scour must be determined by hydraulic engineering methods
acceptable to the city Floodplain Administrator;
5. Storage of materials and equipment, provided that:
a. The material or equipment is not subject to major damage by flooding and is properly
anchored to prevent floatation or downstream movement; or
b. The material or equipment is readily movable within the limited time available after
flood warning. Storage of flammable, toxic, hazardous or explosive materials is
prohibited;
6. Domestic water supply wells, provided that:
a. They are driven or drilled wells located on ground higher than the surrounding
ground to ensure positive drainage from the well;
b. Well casings are watertight to a distance of at least 25 feet below the ground surface;
c. Water supply and electrical lines have a watertight seal where the lines enter the
casing;
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d. All pumps, electrical lines and equipment are either submersible or adequately
floodproofed; and
e. Check valves are installed on main water lines at wells and at all building entry
locations;
7. Substantial improvements to any structure provided that the provisions of subsections C,
D or E of section 38.600.260 are met. In the floodway, the structure must be floodproofed
or elevated on a permanent foundation rather than on fill; and
8. All other artificial obstructions, substantial improvements or nonconforming uses not
specifically listed or prohibited by these regulations.
BMC Sec. 38.600.220. - Same—Permits for flood control works.
A. It is desired that flood control be primarily accomplished by on-site stormwater management,
protection of bank stabilizing vegetation, preserving an unobstructed floodplain and keeping
development away from areas prone to flooding. In the event that adequate flood control
cannot be achieved by these methods, flood control works are allowed within floodways
subject to the issuance of a permit by the city Floodplain Administrator with the following
conditions:
1. Levees and floodwalls are permitted if:
a. The proposed levee or floodwall is designed and construed to safely convey a 100-
year flood; and
b. The cumulative effect of the levee or floodwall combined with allowable floodway
fringe encroachments does not increase the unobstructed base flood elevation more
than one-half foot. The city Floodplain Administrator may establish either a lower or
higher permissible increase in the base flood elevation for individual levee projects
only with concurrence from the state department of natural resources and
conservation and the Federal Emergency Management Agency based upon
consideration of the following criteria:
(1) The estimated cumulative effect of any anticipated future permissible uses; and
(2) The type and amount of existing floodprone development in the affected area;
c. The proposed levee or floodwall, except those to protect agricultural land, is
constructed at least three feet higher than the base flood elevation;
2. Bank stabilization methods provided that:
a. When selecting a bank stabilization method, best management practices consistent
with the intent of this chapter must be used;
b. The bank stabilization method is designed to withstand a 100-year flood;
c. The bank stabilization method does not increase the base flood elevation; and
d. The bank stabilization method will not increase erosion upstream, downstream or
adjacent to the stabilization site;
3. Channelization projects if they do not significantly increase the magnitude, velocity or
base flood elevation in the proximity of the project;
4. Dams provided that:
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a. They are designed and constructed in accordance with the Montana Dam Safety Act
and applicable safety standards; and
b. They will not increase flood hazards downstream, either through operational
procedures or improper hydraulic design.
BMC Sec. 38.600.230. - Same—Permits for water diversions.
A. Permits for the establishment of a water diversion or change in place of diversion will not be
issued if, in the judgment of the city Floodplain Administrator:
1. The proposed diversion will significantly increase the upstream base flood elevation to
the detriment of neighboring property;
2. The proposed diversion is not designed and constructed to minimize potential erosion
from a 100-year flood; and
3. Any permanent diversion structure crossing the full width of the stream channel is not
designed and constructed to safely withstand a 100-year flood.
BMC Sec. 38.600.240. - Same—Prohibited uses.
A. The following artificial obstructions and nonconforming uses are prohibited within the
floodway:
1. New construction of any residential, commercial or industrial structure including
manufactured homes;
2. Encroachments including fill, new construction, alterations, substantial improvements
and other development within the adopted regulatory floodway that would result in
erosion of the embankment, obstruction of the natural flow of waters or increase in flood
levels within the community during the occurrence of the 100-year flood;
3. The construction or permanent storage of an object subject to floatation or movement
during flooding;
4. Solid and hazardous waste disposal, sewage treatment and sewage disposal systems;
5. Storage of toxic, flammable, hazardous or explosive materials; and
6. Alterations of structures unless it can be shown the alteration will not raise flood heights.
BMC Sec. 38.600.250. - Floodway fringe—Uses allowed without permits.
All uses allowed in the floodway, according to the provisions of section 38.600.200 of these
regulations, are also allowed without a permit in the floodway fringe.
BMC Sec. 38.600.260. - Same—Uses requiring permits.
A. When a site specific exemption or relaxation of the standards of section 38.410.100 allows
utilization of a portion of the floodplain, the uses allowed in the floodway subject to the
issuance of a permit, according to the provisions of sections 38.600.210 through 38.600.230,
must also be allowed by permit within the floodway fringe. In addition, new construction,
substantial improvements and alterations to structures are allowed by permit. This includes
but is not limited to residential, commercial and industrial construction and suitable fill to be
allowed by permit from the city Floodplain Administrator, subject to the following conditions:
1. Such structures or fill must not be prohibited by any other statute, regulation, ordinance
or resolution;
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2. Such structures or fill must be compatible with local growth policies;
3. The new construction, alterations and substantial improvements of residential structures
including manufactured homes must be constructed on suitable fill such so that the lowest
floor elevation (including basement) is two feet or more above the base flood elevation.
Any approved suitable fill must be at an elevation no lower than the base flood elevation
and must extend for at least 15 feet, at that elevation, beyond the structure in all directions;
4. The new construction, alteration and substantial improvement of commercial and
industrial structures can be constructed on suitable fill as specified in subsection C of this
section. If not constructed on fill, commercial and industrial structures must be adequately
floodproofed to an elevation no lower than two feet above the base flood elevation.
Floodproofing must be certified by a registered professional engineer or architect that the
floodproofing methods are adequate to withstand the flood depths, hydrodynamic and
hydrostatic pressures, velocities, impact, buoyancy and uplift forces associated with the
100-year flood;
a. If the structure is designed to allow internal flooding of areas below the lowest floor,
use of this space must be limited to parking, loading areas, building access and
storage of equipment or materials not appreciably affected by floodwaters. The floors
and wall must be designed and constructed of materials resistant to flooding to an
elevation no lower than two feet above the base flood elevation. Walls must be
designed to automatically equalize hydrostatic forces by allowing for entry and exit
of floodwaters. Openings may be equipped with screens, louvers, valves, other
coverings or devices which permit the automatic entry and exit of floodwaters;
b. Structures whose lowest floors are used for a purpose other than parking, loading or
storage of materials resistant to flooding must be floodproofed to an elevation no
lower than two feet above the base flood elevation. Floodproofing must include
impermeable membranes or materials for floors and walls and watertight enclosures
for all windows, doors and other openings. These structures must also be designed
to withstand the hydrostatic, hydrodynamic and buoyancy effects of a 100-year
flood; and
c. Floodproofing of electrical, heating and plumbing systems must comply with
sections 38.600.350 through 38.600.390;
5. All manufactured homes placed in the floodway fringe must have the chassis securely
anchored to a foundation system that will resist floatation, collapse or lateral movement.
Methods of anchoring may include, but are not limited to, over-the-top or frame ties to
ground anchors. The following conditions also apply:
a. When a manufactured home is altered, replaced because of substantial damage as a
result of a flood, or replaced on an individual site, the lowest floor must be elevated
two feet above the base flood elevation. The home can be elevated on fill or raised
on a permanent foundation of reinforced concrete, reinforced mortared block,
reinforced piers or other foundation elements of at least equivalent strength; and
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b. Replacement or substantial improvement of manufactured homes in an existing
manufactured home community or subdivision must be raised on a permanent
foundation. The lowest floor must be at least 36 inches above the ground or raised
two feet above the base flood elevation, whichever is less. The foundation must
consist of reinforced concrete, reinforced mortared block, reinforced piers or other
foundation elements of at least equivalent strength;
c. Manufactured homes proposed for use as commercial or industrial structures must
be elevated and anchored, rather than floodproofed;
6. Fill material placed in the floodway fringe must be stable, compacted, well graded,
pervious, generally unaffected by water and frost, devoid of trash or similar foreign
matter, devoid of tree stumps or other organic material, and appropriate for the purpose
of supporting the intended use and/or permanent structure;
7. Roads, streets, highways and rail lines must be designed to minimize increase in flood
heights. Where failure or interruption of transportation facilities would result in danger
to the public health or safety, the facility must be located two feet above the base flood
elevation; and
8. Agricultural structures that have a low damage potential, such as sheds, barns, shelters,
and hay or grain storage structures must be adequately anchored to prevent floatation or
collapse and all electrical facilities must be placed above the base flood elevation;
a. Recreational vehicles, if they are on the site for more than 180 consecutive days or
are not ready for highway use, must meet the elevating requirements of subsection C
of this section.
BMC Sec. 38.600.270. - Floodplain—Prohibited uses.
A. The following artificial obstructions and nonconforming uses are prohibited within the
floodway fringe:
1. Solid and hazardous waste disposal; and
2. Storage of highly toxic, flammable, hazardous or explosive materials. Storage of
petroleum products may be allowed by permit if stored on compacted fill at least two feet
above the base flood elevation and anchored to a permanent foundation to prevent
downstream movement.
BMC Sec. 38.600.280. - Same—Areas with flood elevations and no delineated floodway.
A. A development proposed for a 100-year floodplain, where water surface elevations are
available but no floodway is delineated, may not significantly increase flood velocities or
depths or generally alter patterns of flood flow. The provisions of sections 38.600.250 through
38.600.270 apply to these areas. The city Floodplain Administrator may require a permit
applicant to furnish additional hydraulic data before acting on a permit application for such a
floodplain. The data may include, but are not limited to, any of the following:
1. A hydraulic study documenting probable effect on upstream, downstream or adjacent
property owners' caused by the proposed development; or
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2. The calculated increase in the 100-year floodwater surface profile caused by the proposed
development.
B. Permits for such proposed development may be modified or denied if the additional
information shows that the proposed use would cause an additional flood hazard to adjacent
property or significantly increase flood heights. A significant increase in flood height is one-
half foot unless existing or anticipated development in the area dictates a lesser amount of
allowable increase. BMC Sec. 38.600.290. - Shallow flooding (AO zones).
A. Shallow flooding areas are delineated as AO zone floodplains on the flood insurance rate
maps. The provisions of section 38.600.260 apply to any AO zone floodplains. The depth of
the 100-year flood is indicated as the depth number on the flood insurance rate maps. The
100-year flood depth must be referenced to the highest adjacent grade or stream flow line in
determining which fill or floodproofing heights to use in applying the provisions of
subsections C and D of section 38.600.260. In the absence of depth or elevation information,
a minimum two-foot flood depth must be used.
B. Floodplain boundary interpretation. The city Floodplain Administrator must make
interpretations where needed as to the exact location of an AO zone floodplain boundary
when there is a conflict between a mapped boundary and actual field conditions.
BMC Sec. 38.600.300. - Applicability to unnumbered A zones.
The minimum floodplain development standards listed in this section apply to the 100-year
floodplains delineated by approximate methods and identified as unnumbered A zones on the
flood insurance rate maps.
BMC Sec. 38.600.310. - A zones—Uses allowed without permits.
All uses allowed in a floodway, according to the provisions of section 38.600.210, are also
allowed without a permit in unnumbered A zone floodplains.
BMC Sec. 38.600.320. - Same—Uses requiring permits.
A. All uses allowed in the floodway and floodway fringe subject to the issuance of a permit
according to the provisions of section 38.600.260, require permits from the city Floodplain
Administrator for unnumbered A zone floodplains. Also, the provisions of section 38.600.260
apply to the A zone floodplains with no floodway delineated or water surface profile
computed. Since there are no 100-year floodwater surface profiles computed for A zone
floodplains, the following conditions also apply:
1. Elevation data on the 100-year flood must be provided for subdivision proposals
according to the definitions and rules of the Montana Sanitation in Subdivisions Act, title
76, chapter 4, part 1, Montana Code Annotated (MCA 76-4-101 et seq.) and the rules
adopted by Department of Environmental Quality under this Act. These data must be used
in applying subsections C, D and E of section 38.600.270. Subdivision proposals must
also provide for adequate drainage to minimize potential flood hazards;
2. The city Floodplain Administrator may obtain, review and reasonably use any base flood
elevation and floodway data available from federal, state or other sources, until such data
have been provided by FEMA, to enforce subsections C and D of section 38.600.270;
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3. The city Floodplain Administrator may use historical flood elevations to determine
suitable fill or floodproofing elevations as required by subsections C and D of section
38.600.270;
4. If historical flood evidence is not available, then the city Floodplain Administrator must
determine, from a field review at the proposed development site, an appropriate fill or
floodproofing elevation to use in applying subsections C and D of section 38.600.270. In
the absence of depth or elevation information, a minimum two foot flood depth must be
used; and
5. Proposed structures must be anchored to prevent floatation or collapse and must be
located as far from stream channels as practicable.
BMC Sec. 38.600.330. - Same—Prohibited uses.
Those uses prohibited in the floodway fringe, in accordance with section 38.600.270, are
also prohibited within the A zone floodplain boundaries.
BMC Sec. 38.600.340. - Same—Floodplain boundary interpretation.
The city Floodplain Administrator must make interpretations where needed as to the exact
location of the unnumbered A zone floodplain boundary when there is a conflict between a
mapped boundary and actual field conditions.
BMC Sec. 38.600.350. - Floodproofing requirements—Certification.
If the following floodproofing requirements are to be applied to a proposed structure, as
stipulated by the city Floodplain Administrator in accordance with these regulations, the methods
used must be certified as adequate by a registered professional engineer or architect.
BMC Sec. 38.600.360. - Same—Conformance.
Permitted floodproof systems must conform to the conditions listed in sections 38.600.370
through 38.600.390 and the floodproofing standards listed in subsection D of section 38.600.260
for commercial and industrial structures.
BMC Sec. 38.600.370. - Same—Electrical systems.
A. All incoming power service equipment, including all metering equipment, control centers,
transformers, distribution and lighting panels, and all other stationary equipment must be
located at least two feet above the base flood elevation;
B. Portable or movable electrical equipment may be placed below the base flood elevation, if
the equipment can be disconnected by a single submersible plug-and-socket assembly;
C. The main power service line must have automatic or manually operated electrical disconnect
equipment located at an accessible location outside the 100-year floodplain and above the base
flood elevation; and
D. All electrical wiring systems installed at or below the elevation of the 100-year flood must
be suitable for continuous submergence and may not contain fibrous components.
BMC Sec. 38.600.380. - Same—Heating systems.
A. Float operated automatic control valves must be installed in gas furnace supply lines so that
the fuel supply is automatically shut off when floodwaters reach the floor level where the
furnace is located;
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B. Manually operated gate valves must be installed in gas supply lines. The gate valves must be
operable from a location above the elevation of the 100-year flood; and
C. Electric heating systems must be installed in accordance with the provisions of
International Building Code and any other applicable regulations.
BMC Sec. 38.600.390. - Same—Plumbing systems.
A. Sewer lines, except those to be buried and sealed in vaults, must have check valves installed
to prevent sewage backup into permitted structures; and
B. All toilet stools, sinks, urinals and drains must be located so the lowest point of possible
water entry is at least two feet above the elevation of the 100-year flood.
BMC Sec. 38.600.400. - Violation—Notice.
The city Floodplain Administrator must bring any violation of this division 38.600 to the
attention of the local governing body, its legal counsel and the state department of natural
resources and conservation.
BMC Sec. 38.600.410. - Same—Penalty.
Violation of the provisions of this division 38.600 or failure to comply with any of the
requirements, including permit approval prior to development of floodprone lands, and
conditions and safeguards established are subject to the provisions of division 38.200 of this
chapter.
DIVISION 38.600. – FLOODPLAIN REGULATIONS
Citation.
This division 38.600 is known and may be cited as the city floodplain regulations,
except when cited herein, where it is referred to as “this division”.
Authority.
This division is adopted by authority of Montana Code Annotated (MCA) §§ 76-5-101
et seq.
Findings.
Flooding may cause loss of life, damage to property, disruption of commerce and
essential governmental services, and unsanitary conditions all of which are detrimental
to the health, safety, and welfare of city occupants.
The public interest necessitates management and regulation of flood hazards in a
manner consistent with sound land and water use management practices intended to
prevent and alleviate threats to life and health and reduce private and public economic
losses.
Control, mitigation, and avoidance of flood hazards interacts with other provisions of
public policy that promote public purposes, such as providing water quality and storm
water control; therefore, regulations addressing flood hazards must be correlated with
other water related regulations.
As stated in Bozeman Municipal Code (BMC) Sections 38.100.050 and 38.100.070,
these regulations are minimum requirements and upon review, the review authority may
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determine that the public interest will be best served when such minimum standards are
exceeded. The review authority may impose conditions of approval when such are
found necessary.
Purpose.
This division establishes regulations for development within regulated flood hazard
areas in order to protect public health and safety, safeguard water quality, provide for
wildlife habitat and accomplish other public purposes. There are circumstances where
development within the floodplain either currently exists or may be permitted from time
to time to advance a public purpose. This division provides standards which shall be
met in order to promote the public health, safety and general welfare, to minimize flood
losses in areas subject to flood hazards, and to promote wise use of the floodplain. This
division has been established with the following purposes:
Generally, it is the purpose of this division to guide development of regulated flood
hazards areas within city limits consistent with the enumerated findings of this
division by:
Establishing zoning and subdivision regulations coincident with and applicable
to regulated flood hazard areas with special requirements and regulations to
protect the public health, safety, and welfare;
Recognizing the right and need of watercourses or drainways to periodically
carry more than the normal flow of water;
Participating in coordinated efforts of federal, state and local management
activities for 100-year floodplains;
Striving to ensure the regulations and minimum standards reasonably balance
the greatest public good with the least private injury;
Carrying out the provisions of this division in a fashion consistent with the
remainder of this chapter and the public policies set forth in the city's growth
policy;
Minimizing the need for rescue and relief efforts associated with flooding
undertaken at the expense of the general public;
Complying with minimum standards necessary for continued participation in
the National Flood Insurance Program as a community in good standing; and
Coordinating regulations addressing flood hazards with other regulations
adopted by the city and regulatory requirements imposed on the city by state
and federal agencies.
Specifically, it is the purpose of this division to:
Restrict or prohibit uses that are dangerous to health, safety and property in
times of flood, or that cause increased flood heights and velocities;
Require that developments and uses vulnerable to flood hazards, including
public utilities and facilities, satisfy minimum standards of this division at the
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time of initial construction or substantial improvement to minimize flood
damage;
Identify lands unsuitable for certain development or uses because of flood
hazards;
Distinguish between regulations applied to the regulatory floodway and those
applied to that portion of the regulated flood hazard area not contained within
the regulatory floodway;
Apply more restrictive regulations within the regulatory floodway;
Ensure that those who develop or use land within a regulated flood hazard area
do not increase flood hazards to others and to the surrounding area;
Regulate the alteration of natural floodplains, stream channels, and natural
protective barriers that are needed to accommodate floodwaters; and
Regulate filling, grading, dredging and other development that may increase
flood hazards.
Land use restrictions.
Land subject to being flooded by a flood of 100-year frequency as defined by MCA 76-
5-101 et seq., or land deemed to be subject to flooding by the Floodplain Administrator,
may not be subdivided or developed for new buildings or any new uses that may
increase or aggravate flood hazards to public health, safety, and welfare or damage
property. Lands within a floodplain area are also subject to the restrictions of BMC
Sec. 38.410.100 – Watercourse setback.
Disclosure provision.
All owners of property containing a regulated flood hazard area set forth in BMC Sec.
38.600.110 shall notify potential buyers or their agents that such property is subject to
the provisions of this division.
Abrogation and greater responsibility.
It is not intended by this division to repeal, abrogate, or impair any existing easements,
covenants, deed restrictions, or underlying zoning. However, where this division
imposes greater restrictions, the provisions of this division shall prevail.
Regulation interpretation.
The interpretation and application of the provisions of this division are intended to be
minimum requirements and not deemed a limitation or repeal of any other powers
granted by state statute or self-government status.
Compliance with regulations.
Compliance with this division shall be demonstrated in full prior to approval by the
review authority of any development occurring under this chapter 38 or chapter 10.
Compliance with this division shall also be provided in full prior to establishing,
expanding, or altering an artificial obstruction within a regulated flood hazard area.
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Compliance with this division occurs by issuance of a floodplain permit by the
Floodplain Administrator unless the use, activity, or artificial obstruction is exempt
from the requirement to obtain a floodplain permit.
The issuance of a floodplain permit is independent of, and is in addition to, any other
type of approval required by any other statute or ordinance of the state or any political
subdivision or the United States.
Existing uses, activities and artificial obstructions that were lawful prior to the initial
creation of city floodplain regulations on March 19, 1975, or any repeal and
replacement or amendment thereto, that do not conform to this division are allowed to
remain in the state and location at which they existed at the time they first became
subjected to floodplain regulations without need for a floodplain permit.
Except as provided in subsection D of this section, an artificial obstruction within a
regulated flood hazard area that has not been issued a floodplain permit when one is
required is a public nuisance and subject to chapter 16, article 2.
Floodplain Administrator.
The Floodplain Administrator has been designated by the city commission to be the city
engineer, who may delegate Floodplain Administrator duties to a member of the city
engineering division staff, and has the responsibility and authority of such position as
contained in this division.
Regulated flood hazard areas.
This division applies to all lands within the boundaries of the city that are:
Located within designated special flood hazard areas established by the official
“FEMA Flood Insurance Study of Gallatin County, Montana, and Incorporated
Areas (Flood Insurance Study Number 30031CV001B)” and FEMA Flood
Insurance Rate Maps dated April 21, 2021; and, subject to BMC Sec.
38.600.120.A, any alterations made thereto by letters of map change issued by
FEMA expressly listed in the administrative procedures authorized by BMC Sec.
38.600.160.G.
Otherwise established by DNRC pursuant to MCA 76-5-101 et seq. to be located
within designated floodplains and floodways by a DNRC flood study that is
expressly listed in the administrative procedures authorized by BMC Sec.
38.600.160.G.
Identified as containing flood hazards determined by a flood hazard evaluation
performed in accordance with BMC Sec. 38.600.150.
Independently determined by the Floodplain Administrator through engineering
analysis, or other objective and factual basis, as being subject to flood hazards.
Alterations to regulated flood hazard areas.
Any alterations to a regulatory floodway shall be designed and delineated to carry the
waters of the base flood without increasing the base flood elevation more than 0.50 feet
at any point.
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Substantial natural physical alterations to a flooding source, or new technical or
scientific flood data showing that the base flood elevation or regulatory floodway has
been altered or was erroneously established, must be brought to the attention of FEMA
and DNRC by the Floodplain Administrator when such alteration or error is identified
for a regulated flood hazard area set forth in BMC Sec 38.600.110.A.1.
The official alteration of the base flood elevation or regulatory floodway for a regulated
flood hazard area set forth in BMC 38.600.110.A.1 occurs by a letter of map revision
issued by FEMA. An application for a letter of map revision must be supported by
DNRC and the Floodplain Administrator prior to its submittal to FEMA.
Interpretation of regulated flood hazard area boundaries.
Georeferenced Boundaries. Except where not available, the regulated flood hazard area
boundaries in BMC Sec. 38.600.110 shall be determined by using the official
geographic information system georeferenced boundary data provided by FEMA,
DNRC, or the Floodplain Administrator.
Delineated Boundaries. The exact location of the regulated flood hazard area boundary
shall be delineated where the base flood elevation intersects natural ground. Except as
provided in subsection B.1 of this section, the boundaries of the regulatory floodway
shall be determined from the official flood insurance rate maps and floodway data
tables in the flood insurance study.
The regulatory floodways for the East Gallatin River, Bridger Creek between the
confluence with the East Gallatin River and Story Mill Road, and Bozeman Creek
and its tributaries shall be the georeferenced boundary in subsection A of this
section.
Surveyed Boundaries. The Floodplain Administrator may at its discretion require an on-
site survey and staking of the regulated flood hazard area boundary:
Prior to issuance of any floodplain permit;
For any use, activity, or artificial obstruction under an approved floodplain permit
that is not completed; or
For any use, activity, or artificial obstruction that appears upon reasonable
suspicion and inquiry to be located within the regulated flood hazard area without a
floodplain permit.
A property owner who believes their property has been inadvertently included in a
regulated flood hazard area set forth in BMC Sec. 38.600.110.A.1 may submit scientific
and/or technical information to FEMA in the form of an application for a letter of map
change, which if approved by FEMA may modify the flood insurance rating of a
property. A letter of map change approved by FEMA does not impair or abrogate the
authority of the Floodplain Administrator from independently determining if a property
is subject to flood hazards pursuant to BMC Sec. 38.600.110.A.4 and the provisions of
this division.
Warning and disclaimer of liability.
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This division does not imply that areas located outside of regulated flood hazard areas,
or permitted land uses, will always be totally free from flood hazards or flood damages.
This division does not create a liability or cause of action against the City of Bozeman
or any officer or employee thereof for flood damages that may result from reliance upon
this division.
Flood hazard evaluation.
Except as provided in subsection A.2 of this section, if any portion of a proposed
development contains a watercourse or drainway draining an area of 25 square miles or
more, and regulated flood hazard areas under BMC Sec. 38.600.110 have not been
designated or identified, then the development applicant shall complete a detailed flood
study to delineate the 100-year floodplain and floodway of the watercourse or drainway
in accordance with applicable regulations, standards, and technical guidance provided
by DNRC under its state program for delineation of floodplains and floodways
authorized by MCA 76-5-201.
The detailed flood study shall be prepared and certified by a professional engineer.
The requirement to conduct a detailed flood study may be waived by the Floodplain
Administrator if the development applicant provides written communication from
DNRC stating that DNRC is unwilling or unable to provide technical assistance in
the production of a detailed flood study meeting the applicable regulations and
standards DNRC may have for this purpose.
If the detailed flood study is waived by the Floodplain Administrator, the
development applicant shall prepare a flood hazard evaluation report in
conformance with subsection C of this section, which shall be provided with a
preliminary plat or site plan application.
If any portion of a proposed development contains a watercourse or drainway draining
an area less than 25 square miles, and regulated flood hazard areas under BMC Sec.
38.600.110 have not been designated or identified, then, except as provided in
subsection B.1 of this section, the development applicant shall prepare a flood hazard
evaluation report in conformance with subsection C of this section, which shall be
provided with a preliminary plat or site plan application.
The requirement to provide a flood hazard evaluation report may be waived by the
Floodplain Administrator if the development applicant demonstrates to the
satisfaction of the Floodplain Administrator that the base flood discharge of the
watercourse will not adversely affect the land proposed for development at the time
of concept site plan or subdivision pre-application plan.
Contents of the flood hazard evaluation report shall include the following information at
a minimum:
Certification by a professional engineer that the flood hazard evaluation report is
prepared in accordance with this section;
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Description of any mitigation required to protect the proposed development and
adjacent lands from 100-year flood hazards;
Scaled plan view exhibit(s) showing the following: watercourses and drainways,
property boundaries, existing topographic contours, proposed grading and drainage
contours, existing (pre-project) 100-year floodplain boundary, proposed (post-
project) 100-year floodplain boundary, and proposed project improvements.
Exhibit(s) shall be neat and orderly and contain a linetype legend, north arrow, and
drawing scale;
Hydrologic analysis performed in accordance with standard engineering practices
containing at a minimum: exhibit(s) depicting delineation of overall contributing
drainage basin and individual sub-basins, determination of base flood discharge,
narrative describing the basin delineation approach and hydrologic method(s) used
in discharge determination, and any supporting digital files and outputs produced
for the hydrologic analysis;
Hydraulic analysis performed in accordance with standard engineering practices
containing at a minimum: hydraulic modeling of the base flood discharge for
existing conditions (pre-project) and proposed conditions (post-project), scaled plan
view exhibit(s) depicting modeled cross sections, narrative describing hydraulic
model development and data sources used for critical inputs, description of existing
and proposed hydraulic structures, model outputs of water surface elevation in both
profile and cross section view, and digital model files; and
The report shall be formatted as a PDF document and include all digital supporting
files.
The Floodplain Administrator must review and approve all studies and reports required
under this section and may require additional information from the applicant prior to
approval.
Administration of regulations.
BMC Sections 38.410.100 and 38.600.050 establish a public policy to avoid new
development within floodplains, along with certain exceptions. The administration of
this division must be done in a fashion consistent with the letter and spirit of both these
sections.
The Floodplain Administrator has the authority to review floodplain permit applications
for proposed activities, uses, or artificial obstructions within regulated flood hazard
areas to determine compliance with this division.
The Floodplain Administrator may obtain, review and reasonably use any base flood
elevation and floodway data available from federal, state, or other sources.
At any time after a floodplain permit application has been filed, or a floodplain permit
has been issued and permitted work has not been completed, the Floodplain
Administrator may perform an onsite inspection of the subject property during regular
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work hours without advance notice given to the applicant pursuant to BMC Sec.
38.200.050.
Unless specifically exempt from requirements to obtain a permit, a floodplain permit
must be obtained from the Floodplain Administrator prior to establishing, altering or
performing substantial improvements to a use, activity, or artificial obstruction within
the regulated flood hazard area.
Prior to the issuance of a floodplain permit, the Floodplain Administrator must ensure
all necessary permits have been received from those governmental agencies from which
approval is required by federal and state law and local codes, including but not limited
to: section 404 of the Federal Water Pollution Control Act of 1972, 33 USC 1334;
Endangered Species Act, 16 USC 1531 et seq.; and the Montana Natural Streambed and
Land Preservation Act, MCA 75-7-101 et seq.
The Floodplain Administrator may adopt administrative procedures necessary to
administer the provisions of this division.
The Floodplain Administrator is responsible for ensuring National Flood Insurance
Program prerequisites for the sale of flood insurance pursuant to 44 CFR 59.22(a) are
maintained.
In the event of a disaster declaration affecting properties in the FEMA special flood
hazard area, and as part of the disaster recovery effort, the Floodplain Administrator
upon completion of a cursory street level structure condition survey must notify
property owners that a floodplain permit is required prior to commencement of any
alteration or substantial improvements to buildings and structures damaged, or
substantially damaged, by the declared disaster.
The Floodplain Administrator may, at its discretion, represent the city for any
applications, approvals, or endorsements to FEMA affecting a special flood hazard area.
The Floodplain Administrator may require an applicant to provide additional
information necessary to make an informed determination as to whether a proposed or
existing use, activity, or artificial obstruction within the regulated flood hazard area
meets the requirements of this division. Additional information may include but is not
limited to hydraulic modeling; boundary delineations of the regulated flood hazard area
in accordance with BMC Sec. 38.600.130; and certification by a registered land
surveyor or professional engineer or licensed architect within their areas of professional
expertise that the requirements of this division are satisfied.
The Floodplain Administrator may initiate enforcement actions authorized by this
division if additional information required is not provided.
The Floodplain Administrator must maintain public records pertaining to the
administration of this division, including items such as floodplain permit applications,
issued floodplain permits, FEMA elevation and floodproofing certificates, compliance
certifications, fee receipts, and other relevant documentation.
Subdivision and plan review and approval.
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Any proposed development occurring under division 38.230 or division 38.240 of lands
containing a regulated flood hazard area set forth in BMC Sec. 38.600.110.A.1 shall
satisfy the requirements of this section and BMC Sec. 38.410.100. Proposed
developments shall ensure that:
1. Flood damage potential is minimized;
2. Public utilities and facilities are constructed so as to minimize flood damage; and
3. Water supply and sanitary sewer infrastructure is designed to minimize or eliminate
infiltration.
Except as provided in subsection B.1 of this section, lots within a platted subdivision
shall not contain a regulated flood hazard area set forth in BMC Sec. 38.600.110.A.1 if
such lots are proposed for future residential, commercial, industrial, or other building
construction; or such lots are proposed for the placement of structures or storage of
materials.
1. Dedicated parkland and common open space within a platted subdivision may
contain regulated flood hazard areas.
An exhibit depicting the location of the georeferenced boundaries and the delineated
boundaries of regulated flood hazard areas set forth in BMC Sec. 38.600.110.A.1 in
relation to the proposed development shall be provided with all development
applications. These boundaries shall be shown in accordance with BMC Sec.
38.600.130.
1. If any portion of a proposed lot, building, structure, or permanent materials storage
location is within the georeferenced boundary and is completely outside the
delineated boundary, then a conditional letter of map amendment shall be obtained
from FEMA by the development applicant.
The conditional letter of map amendment application is subject to subsection E
of this section.
The conditional letter of map amendment issued by FEMA shall be provided
with the preliminary plat application or site plan application.
A letter of map amendment issued by FEMA subject to subsection F of
this section shall be provided by the development applicant prior to final
plat approval or receiving a certificate of occupancy.
2. If placement of fill is proposed within the delineated boundary of the flood fringe
to artificially elevate land to be above the base flood elevation, then a conditional
letter of map revision based on fill shall be obtained from FEMA by the
development applicant.
The conditional letter of map revision based on fill application is subject to
subsection E of this section.
The conditional letter of map revision based on fill issued by FEMA shall be
provided with the preliminary plat application or site plan application.
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A letter of map revision based on fill issued by FEMA subject to
subsection F of this section shall be provided by the development
applicant prior to final plat approval or receiving a certificate of
occupancy.
3. If any use, activity, or artificial obstruction is proposed within the delineated
boundary of the regulatory floodway, then the development applicant shall
demonstrate that the carrying capacity of the regulatory floodway is not reduced in
accordance with BMC Sec. 38.600.260.C.
A regulatory floodway encroachment analysis shall be prepared by the
development applicant and initially submitted with a subdivision pre-
application or concept site plan application. The analysis shall be updated with
the preliminary plat application or site plan application to reflect any changes
to the proposed regulatory floodway encroachments.
If the regulatory floodway encroachment analysis indicates that the
proposed use, activity, or artificial obstruction in the regulatory floodway
causes an increase to the existing base flood elevation of more than 0.00
feet, then a conditional letter of map revision shall be obtained from
FEMA by the development applicant in accordance with BMC Sec.
38.600.260.C.2 and be provided with the preliminary plat application or
site plan application.
i. A letter of map revision subject to subsection F of this section shall be
provided by the development applicant prior to final plat approval or
receiving a certificate of occupancy.
4. A floodplain permit application meeting the requirements of this division shall be
prepared by the development applicant and provided to the Floodplain
Administrator for any use, activity, or artificial obstruction located within the
delineated boundary of the regulated flood hazard area. If a conditional letter of
map revision based on fill or a conditional letter of map revision are required under
this section, then they shall be obtained from FEMA by the applicant prior to
floodplain permit approval. The floodplain permit must be issued by the
Floodplain Administrator prior to:
Beginning construction of subdivision improvements, including the placement
of fill, that are located within the regulated flood hazard area for development
occurring under division 38.240; or
Obtaining final site plan approval for development occurring under division
38.230.
A subdivision final plat shall depict on the Conditions of Approval sheet the location of
the regulated flood hazard area, including and pursuant to any letter of map revision or
letter of map revision based on fill approved by FEMA, and base flood elevation data
shall be provided for each lot.
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The Floodplain Administrator must review the conditional letter of map change
application and authorize its submittal to FEMA. FEMA conditional letter of map
change application types include:
Conditional letter of map amendment (CLOMA) – A letter from FEMA stating a
proposed use, activity, or artificial obstruction located on natural ground and not
including the placement of fill would not be inundated by the base flood if
completed as proposed.
Conditional letter of map revision based on fill (CLOMR-F) – A letter from FEMA
stating a parcel of land or portion thereof that is proposed to be elevated by fill
would not be inundated by the base flood if fill is placed on the parcel as proposed.
Conditional letter of map revision (CLOMR) – A letter from FEMA stating a
proposed use, activity or artificial obstruction in the regulatory floodway that
would, upon completion, affect the existing hydrologic or hydraulic characteristics
of the flooding source and result in an alteration of the regulatory floodway or the
base flood elevation, is allowable if the project is completed as proposed.
Submittal of a CLOMR application to FEMA is subject to BMC Sec.
38.600.260.C.2.
The Floodplain Administrator must review the letter of map change application and
authorize its submittal to FEMA. FEMA letter of map change application types
include:
Letter of map amendment (LOMA) – Officially amends the effective special flood
hazard area of a flood insurance rate map by confirming that natural ground is not
inundated by the base flood.
Letter of map revision based on fill (LOMR-F) – Officially revises the effective
special flood hazard area of a flood insurance rate map by confirming that the
parcel of land or portion thereof has been elevated by fill to be above the base
flood.
Letter of map revision (LOMR) – Officially revises the effective special flood
hazard area of a flood insurance rate map and the base flood elevation or regulatory
floodway in the effective flood insurance study. A LOMR usually results in
republishing a portion of the flood insurance rate map.
Floodplain permit application requirements.
A floodplain permit application shall be filed with the Floodplain Administrator and at a
minimum include the following information:
A completed and signed Joint Application for Proposed Work in Montana’s
Streams, Wetlands, Floodplains, and Other Water Bodies;
A copy of all other applicable permits or pending applications required by local,
federal or state law for the proposed project, which may include but are not limited
to a 310 permit, SPA 124 permit, 318 authorization, section 404 permit, 401
certification, and endangered species act section 10 permit;
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A copy of the effective flood insurance rate map with the project site identified;
A scaled plan view exhibit(s) showing:
Linetype legend, drawing scale, and north arrow;
Proposed project site and property lines;
Georeferenced boundary of the regulated flood hazard area per BMC Sec.
38.600.130.A;
Existing and proposed structures;
Existing and proposed utilities;
Proposed excavation and/or fill locations; and
Location of stored or stockpiled materials;
Additional information related to the proposed use, activity or artificial obstruction
that documents compliance with applicable development requirements of this
division;
A written response explaining how each of the factors considered in the decision to
issue a floodplain permit set forth in BMC Sec. 38.600.210.G are satisfied by the
design of the proposed use, activity or artificial obstruction;
Application review fee in the amount established by city commission resolution;
Mailing labels for all adjoining property owners, including those across roads and
across watercourses or drainways; and
The number and format of copies of the floodplain permit application as
established by the Floodplain Administrator shall be submitted. Applications must
include the signature of the applicant and land owner(s), which for properties in
common ownership shall include evidence of proper authority for the owner
signatory.
If the floodplain permit application was prepared by a person other than the
identified property owner or applicant, then the person that prepared the
application shall sign as contractor.
The Floodplain Administrator may require additional information for the floodplain
permit application depending on the nature of the proposed use, activity or artificial
obstruction, including but not limited to:
Scaled topographic plan view exhibit(s) of the project area with 1-foot contours and
elevation values displayed in NAVD88 vertical datum depicting:
Linetype legend, drawing scale, and north arrow;
Existing ground contours certified by a professional engineer or registered land
surveyor;
Location of watercourse or drainway channel and banks;
Delineated boundary of the regulated flood hazard area pursuant to BMC Sec.
38.600.130.B;
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Proposed ground contours and delineation of proposed regulated flood hazard
boundaries pursuant to a conditional letter of map change issued by FEMA;
and
Location of all proposed improvements and artificial obstructions;
Cross sections of the proposed project that clearly differentiate between existing
site conditions and proposed site conditions;
Proposed building elevations showing the elevation of the lowest floor, including
any basement or crawlspace, proposed finished ground elevation, and the base
flood elevation;
Specifications for floodproofing, filling, excavating, grading, bank stabilization,
storage of materials and location of utilities;
Construction plans and specifications for road and utility crossings;
Flood scour analyses for utility crossings and bridge abutment designs;
Construction plans and specifications for stream restoration projects;
A hydraulic model prepared and certified by a professional engineer demonstrating
the impact of the proposed project on the base flood elevations at and proximate to
the project site;
A floodway encroachment analysis and no-rise certification prepared in accordance
with BMC Sec. 38.600.260.C.1 and signed by a professional engineer together with
any hydraulic modeling utilized for the no-rise analysis.
For projects in the regulatory floodway that cause a rise in the existing base flood
elevation, a conditional letter of map revision issued by FEMA;
For a new building, or alteration or substantial improvement to an existing
building, a completed FEMA elevation certificate based on construction drawings;
For projects involving the placement of fill in the flood fringe, a conditional letter
of map revision based on fill issued by FEMA;
A professional engineer's or registered architect's certification within their
respective areas of expertise that the proposed use, activity, or artificial obstruction
has been designed to be in compliance with this division; and
Any other relevant information deemed necessary by the Floodplain Administrator
to demonstrate that the proposed activity, use, or artificial obstruction is in
compliance with this division, the Montana Floodplain and Floodway Management
Act, or the requirements of the National Flood Insurance Program.
Floodplain permit application review.
Within 10 working days of receipt of a floodplain permit application and required
application review fee, the Floodplain Administrator must review the application for
acceptability to determine if the application omits any of the minimum information
required and whether any additional information in sufficient detail and accuracy is
required to enable the Floodplain Administrator to determined compliance with this
division. If the application is determined to not include the minimum information
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required or needs additional information, the Floodplain Administrator must notify the
applicant in writing of the information required to deem the application acceptable. The
applicant shall have 60 working days to provide the required information or a new
floodplain permit application shall be submitted.
The process in subsection A of this section will be repeated until the Floodplain
Administrator determines the application is acceptable. If the application is not deemed
acceptable by the Floodplain Administrator after the third notice, or if the applicant
does not respond to a notice within the timeframe specified, the Floodplain
Administrator may deny the application.
Once the Floodplain Administrator is satisfied that the application is acceptable, the
Floodplain Administrator must review the application for compliance with this division.
A determination that the application is acceptable does not guarantee that the floodplain
permit application will be approved or conditionally approved and does not limit the
ability of the Floodplain Administrator to request additional information during the
compliance review process to ensure conformance with this division.
The Floodplain Administrator must approve, approve with conditions, or deny a
floodplain permit application within 60 working days of receipt of an acceptable
application, except if the applicant in writing agrees to accept an extended timeframe.
Floodplain permit application notice requirements.
Upon receipt of a floodplain permit application deemed acceptable, the Floodplain
Administrator must prepare a notice according to the requirements of division 38.220 of
this chapter. Notice by first-class mail must be provided by the Floodplain
Administrator to adjoining property owners listed in the application.
The Floodplain Administrator must serve notice of the floodplain permit application to
the state National Flood Insurance Program coordinator.
The Floodplain Administrator must provide notice to adjacent communities, the state
National Flood Insurance Program coordinator, and FEMA for any project involving the
alteration or relocation of a watercourse containing a special flood hazard area set forth
in BMC Sec. 38.600.110.A.1.
Floodplain permit issuance.
The Floodplain Administrator may only approve a floodplain permit application and
issue a floodplain permit when the activities, uses or artificial obstructions described in
the floodplain permit application are in full compliance with this division and applicable
provisions of this chapter.
The Floodplain Administrator must issue a written decision to approve, conditionally
approve, or deny a floodplain permit within the timeframe provided by this division.
The applicant must demonstrate to the satisfaction of the Floodplain Administrator that
the floodplain permit application is not in conflict with any other applicable permits
obtained for the proposed use, activity or artificial obstruction prior to floodplain permit
issuance.
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A floodplain permit for a use, activity or artificial obstruction in the regulatory
floodway that causes an increase of more than 0.00 feet to the existing base flood
elevation must not be issued until a conditional letter of map revision, subject to BMC
Sec. 38.600.260.C.2.a, is approved by FEMA.
A letter of map revision may be required by the Floodplain Administrator when a
proposed use, activity, or artificial obstruction in the regulatory floodway is:
1. Certified by a professional engineer to not cause an increase of more than 0.00 feet
in the existing base flood elevation; and
2. The existing base flood elevation or existing regulatory floodway is determined to
be substantially different than the effective base flood elevation or effective
regulatory floodway due to:
Natural physical alterations to the flooding source affecting its plan form and
grade; or
Proposed conditions modeling conducted to evaluate project-related impacts.
A floodplain permit must not be issued until any FEMA conditional letters of map
change required by BMC Sec. 38.600.170 are provided by the applicant.
The Floodplain Administrator must consider the following factors in the floodplain
permit issuance decision:
The danger to life and property due to increased flood heights, increased flood
water velocities or alterations in the pattern of flood flow caused by the proposed
use, activity, or artificial obstruction;
The danger that materials may be swept onto other lands or downstream to the
injury of others;
The construction or alteration of the proposed use, activity, or artificial obstruction
is conducted in such manner as to lessen the flooding danger;
Impacts to water supply and sanitation systems and the ability of these systems to
prevent disease, contamination and unsanitary conditions, and whether sanitation
systems will be located to avoid surcharge during flooding;
The susceptibility of the proposed use, activity, or artificial obstruction to flood
damage and the effects of such damage on the individual owner;
The importance of the services provided by the use, activity or artificial obstruction
to the community;
The proposed use, activity or artificial obstruction will be reasonably safe from
flooding;
The drainage at the site is adequate to reduce exposure to flood hazards;
The requirement of the facility for a water-front location;
The availability of alternative locations not subject to flooding for the proposed
use, activity, or artificial obstruction;
The compatibility of the proposed use, activity, or artificial obstruction with
existing development and anticipated development in the foreseeable future;
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The permanence of the proposed use, activity, or artificial obstruction;
The relationship of the proposed use, activity, or artificial obstruction to any
adopted growth policy or other plans covering the project area;
The safety of access to property in times of flooding for ordinary and emergency
services; and
Such other factors as are consistent with the purposes of this division, this chapter,
the Montana Floodplain and Floodway Management Act and the National Flood
Insurance Program.
The floodplain permit must be issued in the name of the landowner on the floodplain
permit application form. When a floodplain permit is issued the landowner becomes the
permittee and responsible party for all floodplain permit requirements.
Floodplain permit conditions and requirements.
The Floodplain Administrator may attach conditions of approval to a floodplain permit
to ensure compliance with this division and may require reasonable mitigation of
adverse impacts.
The Floodplain Administrator may require the permittee to record a notice of decision
of the floodplain permit in the office of the Gallatin County Clerk & Recorder to notify
successors in interest of the permit requirements and that such property is located in a
regulated flood hazard area.
Completion of the use, activity, or artificial obstruction authorized under the floodplain
permit shall be limited to the scope contained in the floodplain permit application and
any conditions of floodplain permit approval.
The permittee shall submit a compliance report to the Floodplain Administrator within
30 days of project completion, or other timeframe as may be specified by the Floodplain
Administrator, that certifies that the permitted use, activity, or artificial obstruction was
completed in accordance with the approved permit. The compliance report shall
include any letters of map change approved by FEMA applicable to the project as well
as applicable FEMA floodproofing certificates and FEMA elevation certificates.
The permittee shall maintain the permitted use, activity, or artificial obstruction in
compliance with the floodplain permit.
The permitted use, activity, or artificial obstruction must be completed within one year
from the date of floodplain permit issuance, or a completion timeline identified in the
floodplain permit application that is determined reasonable by the Floodplain
Administrator, whichever is later.
The Floodplain Administrator may require the permittee to provide periodic oversight
by a professional engineer or licensed architect and provide interim reports during the
construction period.
The Floodplain Administrator may require the permittee to submit annual performance
and maintenance reports for a period of up to 5 years, or a time specified in the
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floodplain permit, for bank stabilization or stream restoration projects utilizing
vegetative components.
For uses, activities, and artificial obstructions in which a conditional letter of map
revision has been approved by FEMA, or for those projects in the regulatory floodway
that Floodplain Administrator has determined under BMC Sec. 38.600.210.E that a
letter of map revision is required, the permittee shall prepare and submit a letter of map
revision application to FEMA, and applicable application fees, within 6 months of
project completion and shall pursue the application until FEMA issues approval.
Failure to do so constitutes a violation of this division.
Extensions to floodplain permit approval period.
The permittee may request an extension of the duration of the floodplain permit
approval. The extension request must be made in writing not less than 30 days before
the permit expiration date and present the reasons for which the request is being made
along with a description of work completed and work remaining. The Floodplain
Administrator may approve, conditionally approve, or deny the extension request. If a
permittee requests an extension within 30 days before the permit expiration date, the
permittee must pay an additional floodplain permit application fee.
If the permittee makes an extension request after the permit has expired, the Floodplain
Administrator may require the permittee to file a new floodplain permit application for
review and approval. The new floodplain permit application must present the reasons
for which the new application is being made along with a description of the work
completed and work remaining. The Floodplain Administrator may approve,
conditionally approve, or deny the new floodplain permit application.
Uses, activities, and artificial obstructions within regulated flood hazard
areas exempt from floodplain permitting, but subject to BMC Sec.
38.410.100.
Any use, activity, or artificial obstruction within the regulated flood hazard area
established by BMC Sec. 38.600.110.A.3 is exempt from obtaining a floodplain permit,
unless upon the discretion of the Floodplain Administrator a floodplain permit is
determined to be required.
The following open space uses, activities, and artificial obstructions shall be allowed in
regulated flood hazard areas without obtaining a floodplain permit, provided they are
not prohibited by this chapter or state statute, do not require buildings or structures, and
do not require fill, grading, excavation, or storage of materials or equipment:
Agricultural uses such as tilling, farming, irrigation, ranching, harvesting, and
grazing, but not including structures related to agricultural uses;
Forestry uses, including processing of forest products with portable equipment;
Recreational vehicle use or storage, provided that the vehicle is on the site for
fewer than 180 consecutive days or the vehicle is fully licensed and ready for
highway use. A recreational vehicle is ready for highway use if it is on its wheels
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or jacking system with wheels intact, is attached to the site only by quick
disconnect type utilities and security devices, and has no permanently attached
additions;
Residential uses such as lawns, gardens, and play areas;
Maintenance of existing open space uses that do not increase the flood hazard
potential;
Preventive maintenance activities for transportation infrastructure such as bridge
deck rehabilitation and roadway pavement preservation activities that are not
considered alterations;
Public or private recreational uses that do not include structures such as picnic
grounds, swimming areas, parks, golf courses, driving ranges, archery ranges,
wildlife management and natural areas, alternative livestock ranches (game farms),
fish hatcheries, shooting preserves, target ranges, trap and skeet ranges, hunting and
fishing areas, and hiking and horseback riding trails;
Fences that have a low impact to the flow of water such as barbed wire fences and
wood rail fences, except permanent fences crossing channels. Fences that have the
potential to stop or impede water flow or debris require a floodplain permit;
Addition of roadway guardrail, signing and utility poles that have a low impact to
the flow of water along an existing roadway; and
Irrigation and livestock supply wells, provided that they are located at least 500 feet
from domestic water supply wells and the top of the well casing is 18” above the
base flood elevation.
Uses, activities, and artificial obstructions prohibited within regulated
flood hazard areas.
The following uses, activities, and artificial obstructions are prohibited in the regulatory
floodway:
New buildings and structures, including appurtenant or accessory buildings and
structures, used for any purpose;
Uses, activities, or artificial obstructions, that cause water to be diverted from the
regulatory floodway, cause erosion, obstruct the natural flow of water, or reduce
the carrying capacity of the floodway;
Construction or storage of artificial obstructions subject to flotation or movement
during flood level periods;
Solid or hazardous waste disposal systems;
Onsite wastewater treatment systems;
Public and private campgrounds, and buried and sealed vaults for sewage disposal
in campgrounds and recreational areas;
Domestic water supply wells;
Storage of toxic, flammable, hazardous or explosive materials; and
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Mining or excavation of material from pits or pools not in connection with a
channelization, streambank restoration, or stream stabilization project.
The following uses, activities, and artificial obstructions are prohibited in the flood
fringe:
Construction or storage of an artificial obstruction subject to flotation or movement
during flood levels, if the Floodplain Administrator determines the flotation or
movement of the artificial obstruction would pose a risk to public health, welfare,
or safety;
Solid or hazardous waste disposal systems;
Onsite wastewater treatment systems;
Public and private campgrounds, and buried and sealed vaults for sewage disposal
in campgrounds and recreational areas;
Domestic water supply wells; and
Storage of toxic, flammable, hazardous or explosive materials.
Placement of fill to elevate land not otherwise performed in connection with a
proposed development occurring under chapter 38 or chapter 10.
The following uses, activities, and artificial obstructions are prohibited in regulated
flood hazard areas without a regulatory floodway and flood fringe:
Uses, activities and artificial obstructions prohibited by subsection B of this
section; and
Any use, activity, or artificial obstruction that causes an increase of more than 0.50
feet to the base flood elevation.
Development requirements for uses, activities, and artificial obstructions
permitted in the regulatory floodway subject to issuance of a floodplain
permit and BMC Sec. 38.410.100.
When a site specific exemption or relaxation of the standards of BMC Sec. 38.410.100
allow utilization of a portion of the regulated flood hazard area, the uses, activities and
artificial obstructions contained in this section, including alterations and substantial
improvements to existing artificial obstructions, may be permitted in the regulatory
floodway subject to the issuance of a floodplain permit by the Floodplain
Administrator.
All uses, activities and artificial obstructions permitted in the regulatory floodway shall
be designed and constructed to minimize flood damage and ensure they do not
adversely affect the flood hazards of other properties or be swept downstream to the
injury of others.
The applicant must assure that all uses, activities and artificial obstructions do not
reduce the carrying capacity of the regulatory floodway by:
Providing a regulatory floodway encroachment analysis, prepared and certified by a
professional engineer, demonstrating that the use, activity, or artificial obstruction
does not cause an increase to the existing base flood elevation of more than 0.00
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feet (“no-rise”) and does not significantly increase the velocity of flow. Except as
provided in subsection C.1.a of this section, the no-rise analysis shall be prepared
in accordance with FEMA guidance for no-rise certifications for developments in
regulatory floodways.
At the discretion of the Floodplain Administrator, a different approach to
demonstrate and certify no-rise may be allowed given the scope and nature of
the proposed use, activity, or artificial obstruction. The approach used shall be
acceptable to the Floodplain Administrator and be performed in accordance
with standard engineering practice.
Providing a conditional letter of map revision approved by FEMA, the application
for which must first be supported by the Floodplain Administrator and the DNRC
subject to subsection C.2.a of this section, for any use, activity, or artificial
obstruction that causes an increase to the existing base flood elevation of more than
0.00 feet, or significantly increases the velocity or flow of the watercourse or
drainway, or substantially alters the location of the regulatory floodway.
A conditional letter of map revision is a prospective alteration of the regulated
flood hazard area and is subject to MCA 76-5-203. Alterations to the
regulatory floodway must be designed and delineated so as to carry the waters
of the base flood without increasing the base flood elevation more than 0.50
feet at any point. Written support to file a conditional letter of map revision
application with FEMA shall be obtained from DNRC and the Floodplain
Administrator by the applicant providing the following information to DNRC
and the Floodplain Administrator:
Certification that no buildings are located in areas impacted by increased
base flood elevations;
Information demonstrating that alternative designs or approaches that do
not cause an increase to the base flood elevation are not feasible;
Any other information required by DNRC or the Floodplain Administrator
to gain support for the filing of a conditional letter of map revision
application with FEMA.
Substantial improvement to existing buildings and alteration of existing structures may
be permitted, provided that:
All applicable requirements in BMC Sec. 38.600.270 are met;
The existing building or structure shall not be elevated by means of new or
additional fill; and
An alteration to expand the horizontal dimensions of an existing building is not
occurring.
Watercourse crossings for pedestrian and transportation facilities may be permitted,
provided that:
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Crossings shall be generally oriented as perpendicular to the direction of flow as
practicable;
Footings for bridge piers and abutments shall be buried below the maximum
calculated depth of scour during the base flood discharge as calculated and certified
by a professional engineer;
Where failure or interruption of public transportation facilities would result in
danger to public health or safety, and wherever practicable:
a. Bridge low chord elevations shall have at least two feet of freeboard above the
base flood elevation;
b. Culverts shall be designed to pass the base flood discharge and provide at least
two feet of freeboard to the crossing surface; and
Except for those public bridges maintained by the Montana Department of
Transportation, bridges for public transportation facilities shall meet applicable
design and construction standards established by Gallatin County by authority of
MCA 7-14-2204.
Limited filling for transportation facility embankments not in connection with
watercourse crossings may be permitted, provided that:
Fill placed is a suitable material for the transportation facilities;
Reasonable alternate transportation routes outside the regulatory floodway are not
available; and
The floodway encroachment is located as far from the stream channel as possible.
Buried or suspended utility transmission and service lines may be permitted, provided
that:
Suspended utility lines are designed such that the lowest point of the suspension is
at least six feet higher than the base flood elevation;
Towers, poles, and other appurtenant structures are designed and placed to
withstand and offer minimal obstruction to flood flows;
Alternatives routes, directional drilling, and aerial routes are considered when
practicable; and
Utility transmission and service lines carrying toxic or flammable materials are
buried to a depth of at least twice the maximum scour depth for the base flood
discharge as calculated and certified by professional engineer.
Storage of materials and equipment not otherwise prohibited may be permitted,
provided that:
The material or equipment is not subject to damage by flooding and is properly
anchored to prevent flotation or downstream movement; or
The material or equipment is readily removable within the limited time available
after flood warning.
Construction or alteration of surface water diversion structures may be permitted,
provided that:
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Potential erosion from a base flood shall be minimized; and
A professional engineer shall design and certify that any permanent diversion
structure in the watercourse or drainway can withstand hydrodynamic, hydrostatic,
buoyancy, and scour forces associated with the base flood discharge as well as ice
damage and debris impacts.
Construction or alteration of levees and floodwalls may be permitted, provided that:
A professional engineer shall design and certify that the levee or floodwall can
withstand hydrodynamic, hydrostatic, buoyancy, and scour forces associated with
the base flood discharge as well as ice damage and debris impacts;
Materials used for construction are suitable materials designed to withstand the
base flood discharge;
Constructed height shall be at least 3 feet higher than the base flood elevation;
All state and federal levee and floodwall engineering and construction standards are
met; and
If the levee or floodwall protects structures of more than one landowner, it shall be
publicly owned and maintained.
Streambank, pier and abutment stabilization or protection projects may be permitted,
provided that:
A professional engineer shall design and certify that the project can withstand
hydrodynamic, hydrostatic, buoyancy, and scour forces associated with the base
flood discharge;
Materials used and construction methods employed are the least environmentally
damaging practicable for the proposed application;
Vegetative components, if any, must be established and mature within five years of
installation, or other timeframe as may be required by the Floodplain
Administrator, and once established and mature do not require substantial yearly
maintenance;
If materials for the project are designed to biodegrade or erode over time they shall
not fail catastrophically to the impact of others and the design amount and rate of
erosion shall be similar to what existing stable natural streambanks experience
during the base flood discharge; and
Potential erosion upstream, downstream, across from or adjacent to the project site
during the base flood discharge shall not be increased beyond the erosion rate of
existing stable natural streambanks.
Channelization projects may be permitted, provided that:
The requirements of subsection K of this section shall be met; and
The excavation and construction of the stream channel is for the purpose of altering
or relocating a watercourse or drainway and diverting the entire flow of the stream,
or a portion thereof, from its presently established course and shall accommodate
and not increase the magnitude or velocity of the base flood discharge;
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A conditional letter of map revision must be approved by FEMA pursuant to
subsection C.2 of this section.
Stream and bank restoration projects may be permitted, provided that:
The intent of the project is to reestablish the terrestrial and aquatic attributes of a
natural stream and is not for the protection of a structure or a streambank
stabilization project; and
The requirements of subsections K and L of this section are satisfied, except for the
requirement to obtain a conditional letter of map revision, which may not be
required in all instances depending upon the extent and nature of the stream or bank
restoration project.
Dams may be permitted, provided that:
Design and construction shall be in accordance with the Montana Dam Safety Act,
MCA 85-15-101 et seq.;
The project shall not increase the flood hazards downstream either through
operational procedures or improper hydrologic or hydraulic design; and
A conditional letter of map revision must be approved by FEMA pursuant to
subsection C.2 of this section.
Development requirements for uses, activities and artificial obstructions
permitted in the flood fringe subject to issuance of a floodplain permit
and BMC Sec. 38.410.100.
When a site specific exemption or relaxation of the standards of BMC Sec. 38.41.100
allow utilization of a portion of the regulated flood hazard area, the uses, activities and
artificial obstructions contained in this section, including alterations and substantial
improvements to artificial obstructions, may be permitted in the flood fringe subject to
issuance of floodplain permit.
All uses, activities, and artificial obstructions permitted in the regulatory floodway
pursuant to BMC Sec. 38.600.260 may also be permitted in the flood fringe subject to
issuance of a floodplain permit by the Floodplain Administrator.
The requirements of this section shall also apply to uses, activities and artificial
obstructions located in a regulated flood hazard area without a regulatory floodway and
flood fringe, subject to:
An encroachment analysis shall be prepared and certified by a professional
engineer demonstrating that the use, activity, or artificial obstruction in the
regulated flood hazard area does not increase the identified base flood elevation
more than 0.5 feet and does not significantly increase flood velocities or alter flood
hazards to the detriment of upstream, downstream, or adjacent properties.
The new construction, alteration, and substantial improvement of residential and non-
residential buildings and structures may be permitted, provided that:
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Such buildings and structures shall conform to the requirements of this chapter and
chapter 10 and are not prohibited by any other statute, regulation, ordinance or
resolution;
Such buildings and structures are compatible with local growth policies;
Such buildings and structures are constructed by methods and practices that
minimize flood damage, and are reasonably safe from flooding and anchored to
resist flotation, collapse and lateral movement;
Grading around such buildings and structures is provided with adequate surface
drainage;
All materials used for construction are resistant to flooding to an elevation at least
two feet above the base flood elevation;
New construction, alteration, and substantial improvement of residential buildings
and structures, including manufactured homes, shall be elevated so that the lowest
floor is at least two feet above the base flood elevation by any of the following
means:
On suitable structural fill, foundation wall enclosure, stem walls, pilings, posts,
piers, columns or other acceptable means.
If elevated on suitable structural fill, the fill must be extended at an elevation
no lower than the base flood elevation for a minimum distance of 15 feet in all
directions beyond the foundation walls, unless physical constraints exist that
make strict compliance impracticable and the Floodplain Administrator
approves a lesser distance, and be certified by a professional engineer to meet
the following:
Fill material must be suitable for its intended purpose and be clean, well
graded, pervious, not adversely affected by water and frost, devoid of trash
or similar foreign matter, and free of tree stumps or other organic material;
Fill material must be compacted to 95 percent of its maximum density as
determined by standard proctor testing in accordance with ASTM D698
standards;
Fill must not be placed within the regulatory floodway; and
Fill slope must be less than 1.5:1 unless physical constraints exist, in
which case a retaining wall is allowed if the wall is adequately protected
from erosion;
For new placement, substantial improvement, or replacement of manufactured
homes, including those used for non-residential purposes, the building chassis shall
be secure and resist flotation, collapse and lateral movement by anchoring with
components capable of carrying a force of 4,800 pounds in addition to the
following:
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For manufactured homes less than fifty feet long, over-the-top ties to ground
anchors shall be provided at each of the four corners of the building, with two
additional ties provided per side at intermediate locations; or
For manufactured homes more than fifty feet long, frame ties to ground
anchors shall be provided at each corner of the building, with five additional
ties per side provided at intermediate points;
Non-residential buildings and structures shall be elevated so that the lowest floor is
at least two feet above the base flood elevation in accordance with requirements of
subsection D.6 of this section or shall be certified by a professional engineer or
registered architect to be adequately floodproofed in accordance with the following:
The lowest floor of the building or structure must be adequately wet or dry
floodproofed to an elevation at least two feet above the base flood elevation;
The building or structure shall be designed to withstand hydrostatic,
hydrodynamic, and buoyancy forces of the base flood;
Wet floodproofing is only permitted when the lowest floor of a building or
structure is used for parking, loading, or storage of equipment or materials not
appreciably affected by floodwater,
Wet floodproofing must provide adequate openings to equalize hydrostatic
forces; and
Dry floodproofing must not allow floodwaters to cause internal flooding of the
building or structure by using impermeable membranes and materials for
construction of floors and walls, and must ensure that all windows, doors and
other openings are watertight and do not allow the passage of floodwaters;
Except as provided in subsection D.9.a of this section, appurtenant or accessory
buildings and structures for residential, non-residential, and agricultural purposes
shall be elevated or floodproofed to an elevation at or above the base flood
elevation and be adequately anchored to resist flotation, collapse and lateral
movement. Means of elevating or floodproofing shall be in accordance with
subsections D.6 and D.8 of this section.
a. Attached and detached garage structures used exclusively for parking or
storage of equipment and materials not appreciably affected by floodwater
shall be elevated in accordance with subsection D.6 of this section.
The floor elevation of any crawlspace foundation enclosures, including subgrade
crawlspaces with a floor elevation no more than two feet below the lowest adjacent
grade of the building on all sides, shall be at or above the base flood elevation and
contain flood openings designed and certified by a professional engineer to meet or
exceed the following:
Equalize hydrostatic forces on foundation walls by allowing the automatic
entry and exit of floodwaters through screens, louvers, valves, or other covers
or devices;
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Have two or more openings with a total net area of not less than one square
inch for every one square foot of enclosed area below the lowest floor.
Openings shall be located on a minimum of two walls, except for subgrade
crawlspace enclosures where a minimum of two openings may be provided on
a single wall; and
The bottom of all openings shall be no higher than one foot above the higher of
the exterior adjacent grade elevation or the crawlspace floor elevation;
Basements are considered the lowest floor of a building and shall be elevated two
feet or more above the base flood elevation. A basement includes any floor that is
more than two feet below the lowest adjacent grade of the building on all sides.
All electrical systems shall be certified by a professional engineer to satisfy all
applicable flood hazard area provisions of the current adopted building codes set
forth in chapter 10 along with the following requirements. If conflicts exist
between this division and chapter 10, then chapter 10 requirements shall govern.
All incoming power service equipment including all metering equipment,
control centers, transformers, distribution and lighting panels, and all other
stationary equipment shall be located at least two feet above the base flood
elevation;
Portable and movable electrical equipment may be placed below the base flood
elevation, provided that the equipment can be disconnected by a single plug
and socket assembly of the submersible type;
The main power service lines must have automatically operated electrical
disconnect equipment or manually operated electrical disconnect equipment
located at an accessible remote location outside the regulated flood hazard area
or shall be two feet above the base flood elevation; and
All electrical wiring systems installed below the base flood elevation shall be
suitable for continuous submergence and may not contain fibrous components;
All mechanical systems shall be certified by a professional engineer to satisfy all
applicable flood hazard area provisions of the current adopted building codes set
forth in chapter 10 along with the following requirements. If conflicts exist
between this division and chapter 10, then chapter 10 requirements shall govern.
Float operated automatic control valves shall be installed so that fuel supply is
automatically shut off when flood waters reach the floor level where
mechanical systems are located;
Manually operated gate valves shall be installed on gas supply lines. The gate
valves shall be operable from a location above the base flood elevation;
Electrical components of the HVAC systems shall meet the requirements of
subsection D.12 of this section; and
Furnaces, cooling units, and all associated ductwork shall be installed at least
two feet above the base flood elevation.
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All plumbing systems shall be certified by a professional engineer to satisfy all
applicable flood hazard area provisions of the current building codes set forth in
chapter 10 along with the following requirements. If conflicts exist between this
division and chapter 10, then chapter 10 requirements shall govern:
The building sewer line shall have a backwater valve installed to prevent
sewage backup into the building; and
All toilets, stools, sinks, urinals, vaults, and drains shall be located so the
lowest point of possible flood water entry is at least two feet above the base
flood elevation.
Recreational vehicles may be permitted, provided that:
Recreational vehicles that are on site for more than 180 days out of the year, or are
not ready for highway use, shall meet the manufactured home requirements in
subsections D.6 and D.7 of this section.
Mining or excavation of material from pits or pools provided that:
1. A buffer strip of undisturbed land of sufficient width to prevent the base flood from
channeling into the mine or excavation is left between the edge of the channel and
the edge of the mine or excavation;
2. The mine or excavation meets all applicable laws and regulation of other local and
state agencies; and
3. Mined or excavated material is stockpiled outside of the regulatory floodway.
All other uses, activities and artificial obstructions not otherwise prohibited by BMC
Sec. 38.600.250.B or any other provision of chapter 38 may be permitted in the flood
fringe subject to issuance of a floodplain permit.
Waiver of floodplain permit requirements prior to undertaking
emergency repair or replacement or temporary protective measures.
This division is not intended to prevent a person or entity from taking temporary
protective measures necessary to safeguard life, buildings, or structures during periods
of flooding emergency. A person or entity shall make a reasonable effort to notify the
Floodplain Administrator prior to initiating such temporary protective measures within
the regulated flood hazard area. If prior notice is not practical, a person or entity shall
provide notice to the Floodplain Administrator in all cases no later than five days after
the temporary protective measure was undertaken. Temporary protective measures
shall not be located in the channel of the regulatory floodway or increase the flood
hazard to others, and shall be entirely removed upon cessation of the flooding
emergency.
Emergency repair and replacement of severely damaged public transportation facilities,
public water and sewer facilities, public utility electricity and natural gas distribution
facilities, and flood control works may be authorized and floodplain permit
requirements waived prior to undertaking such emergency work if:
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Upon notification and prior to emergency repair and/or replacement, the Floodplain
Administrator determines that an emergency condition exists warranting immediate
action; and
The Floodplain Administrator agrees upon the nature and type of proposed
emergency repair and/or replacement.
Authorization to undertake such emergency repair and replacement work may be
given orally if the Floodplain Administrator believes that a written authorization
would unduly delay the emergency works. Such oral authorization must be
followed by a written authorization describing the emergency condition, the type of
emergency work agreed upon, and a statement that oral authorization had been
previously given.
Nothing in this section impairs or abrogates the authority of the Floodplain
Administrator from requiring a floodplain permit be obtained retroactively by a person
or entity undertaking emergency repair, replacement, or temporary protective measures
upon cessation of the emergency conditions that gave rise to the emergency repair,
replacement, or temporary protective measures. The Floodplain Administrator may
require the permittee to complete remedial work or activities necessary to achieve
compliance with this division.
Variances.
A variance from the minimum requirements of this division may be authorized as set
forth in this section and division 38.250 of this chapter. The granting of a variance by
the review authority authorizes the Floodplain Administrator to issue a floodplain
permit that otherwise would conflict with the minimum requirements of this division.
In no case may the review authority authorize a variance from a use, activity, or
artificial obstruction prohibited by state or federal law.
In addition to submittal materials for variances set forth in BMC Sec. 38.220.160, a
variance from the minimum requirements of this division shall be accompanied by a
floodplain permit application deemed acceptable by the Floodplain Administrator
pursuant to BMC Sec. 38.600.190, and be noticed publicly pursuant to Table
38.220.420.
Variances may be issued for the repair, rehabilitation or substantial improvement of a
structure designated as historic by the U.S. Secretary of Interior or an approved state or
local government historic preservation program upon a determination that the proposed
repair, rehabilitation or substantial improvement will not preclude the continued
designation of the structure as a historic structure and the variance is the minimum
necessary to preserve the historic character and design of the structure.
Variances from this division shall conform to 44 CFR 60.6(a) and ARM 36.15.218.
The Floodplain Administrator must maintain records of variance notifications and
actions, including justifications for variance issuance, and forward all variance actions
to the DNRC and FEMA upon disposition.
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Appeals.
Appeals from administrative project decisions or administrative interpretations made
under this division may be taken as set forth in division 38.250 of this chapter. Appeal
submittal materials applicable under division 38.220 shall be provided.
Enforcement.
It is the intent to provide for the efficient, reasonable, and impartial enforcement of this
division through the Floodplain Administrator and to set forth the basic procedures for
compliance with, and remedies for, violations of this division.
Any person may file a complaint with the Floodplain Administrator whenever a
violation of this division is alleged to have occurred.
The complaint must be provided to the Floodplain Administrator in writing, state
fully the facts supporting it, and signed by the complainant. If the complaint is
filed by three titleholders of land which may be affected by the alleged violation,
the Floodplain Administrator must perform an investigation to determine whether a
violation of this division has occurred. The names and addresses of the
complainants are a matter of public record.
The Floodplain Administrator may make reasonable entry upon any lands and waters
for the purpose of making an investigation, inspection or survey to verify compliance
with this division and may do so upon the Floodplain Administrator’s own initiative if
the Floodplain Administrator has reasonable suspicion to believe a violation under this
division has occurred.
The Floodplain Administrator must give notice of entry by mail, electronic mail,
phone call, or personal delivery to the owner, owner’s agent, lessee, or lessee’s
agent on whose lands entry is requested.
If none of these persons can be found, the Floodplain Administrator must affix
notice to one or more conspicuous places on the property.
After an investigation, the Floodplain Administrator must provide notice to any person
or entity believed to be responsible for a violation of this division of such violation and
must bring any violation to the attention of the local governing body, its legal counsel,
and the DNRC.
The notice of violation may be in the name of the city and may order the cessation
of the violation and require that a corrective action plan be provided within a period
of time deemed reasonable by the Floodplain Administrator.
Such notice of violation must be sent by mail or other means and is subject to
appeal pursuant to BMC Sec. 38.600.300.
Failure to comply with a cessation order or requirement for corrective action is
cause for the city to initiate any legal remedy it may have including but not limited
to those remedies established in BMC Sections 38.200.160 and 1.01.210.
Penalty.
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Violation of the provisions of this division or failure to comply with the requirements of
a floodplain permit are subject to the provisions of BMC Sections 38.200.160 and
1.01.210.
Section 2
A new Sec. 38.220.180 be added to DIVISION 38.220 – APPLICATIONS AND NOTICING,
Part 1. – Submittal Materials and Requirements as follows:
Sec. 38.220.180 – Submittal materials for regulated flood hazard areas.
Applicable submittal materials required under section 38.600.150. – Flood hazard
evaluation and section 38.600.170. – Subdivision and plan review and approval
must be provided.
Section 3
Sec. 38.230.030 – Special development proposals – Additional application requirements,
review procedures and review criteria. be amended as follows with all remaining text
remaining as is:
Sec. 38.230.030.A.2.d. - Division 38.620, Bozeman 38.600, Floodplain Regulations; and
Sec. 38.230.030.B.7. - Division 38.610 38.600, Floodplain Regulations; and
Section 4
Sec. 38.410.100. – Watercourse setback. be amended as follows with all remaining text
remaining as is:
Sec. 38.410.100.A.2.c.(4)(a). – The setback must extend to the edge of the delineated boundary
of the regulated flood hazard area per Sec. 38.600.130.B any delineated 100-year floodplain if
the regulated flood hazard boundary floodplain is larger than the setbacks established in this
subsection 2.c;
Section 5
Chapter 16 – ENVIRONMENT AND HEALTH, Article 2. – NUISANCES be amended as
follows with all other text remaining as is:
Sec. 16.02.050. - Public nuisances.
A. The following are declared to be public nuisances:
1. Any building or structure which meets the definition of an unsafe building or
structure as provided in section 116 of the International Building Code, or any
successor provision, adopted pursuant to section 10.02.010.
2. Any violation of chapter 38 relating to the city's subdivision and zoning laws and
regulations.
3. Any imminent life safety hazard which creates a present and immediate danger to
life, property, health or public safety.
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4. An artificial obstruction within a regulatory floodway that does not have a
floodplain permit required by division 38.600.
B. The following may be declared to be public nuisances:
1. Any condition which constitutes an attractive nuisance whether within a structure
or on the premises.
2. Any building or place which has been operated or maintained in a manner that has
resulted in repeated disruptive activities including, but not limited to, disturbances
of the peace, public drunkenness, drinking in public, harassment of passersby, sale
of stolen goods, public urination, theft, assaults, batteries, acts of vandalism,
excessive littering, illegal parking, loud noises (particularly in late night or early
morning hours), traffic violations, or police detentions and arrests.
3. Any condition which renders air, food or drink unwholesome, unsanitary or
detrimental to health.
4. Any condition which poses a fire hazard.
5. Any condition in violation of chapter 8 (Animals).
6. The ownership, maintenance or operation of a dog or animal kennel without proper
provisions for the protection of the surrounding properties from odor and sound
generated by the kennel.
7. The keeping, storage, depositing or accumulation on the premises for an
unreasonable period of time of any personal property or wastes, including, but not
limited to, abandoned, wrecked, dismantled or inoperative vehicles, abandoned,
wrecked, or dismantled boats or vessels, automotive parts and equipment,
appliances, furniture, containers, packing materials, scrap metal, wood, building
materials, junk, rubbish, debris, dirt, sand, gravel, concrete or other similar
materials which is within the view of persons on adjacent or nearby real property or
the public right-of-way and which is detrimental to the public health, safety and
general welfare. However, building materials being used or to be used for a project
of repair or renovation for which a building permit has been obtained may be stored
for such period of time as is necessary to expeditiously complete the project.
8. Any public nuisance as defined in MCA 45-8-111 or otherwise recognized in law
as constituting a public nuisance.
9. An artificial obstruction within the flood fringe that does not have a floodplain
permit required by division 38.600.
Sec. 16.02.070. – Summary abatement.
A. Whenever a complaint is made to the department of community development of the
existence of a public nuisance, as defined in section 16.02.040 or 16.02.050, the
department of community development shall promptly cause to be inspected the
property on which it is alleged that such public nuisance exists. Should the department
of community development find that a public nuisance exists, and that the public health,
safety or welfare may be in immediate danger, then summary abatement procedures
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shall be implemented and the department of community development may cause the
nuisance to be removed or abated. The department of community development may
notify the building inspector if the public nuisance involves a building that appears
structurally unsafe. The building inspector, upon being notified by the department of
community development, shall cause the building on which it is alleged such public
nuisance exists to be inspected and submit a written report of such inspection and the
findings to the department of community development. The department of community
development may notify the Floodplain Administrator if the public nuisance involves an
artificial obstruction within the regulated flood hazard area. The Floodplain
Administrator, upon being notified by the department of community development, shall
cause the artificial obstruction on which it is alleged such public nuisance exists to be
inspected and submit a written report of such inspection and the findings to the
department of community development.
Section 6
DIVISION 38.700. – TERMS AND INTERPRETATION be amended as follows with all
remaining text remaining as is:
Sec. 38.700.020. – A definitions
Activity. A thing that a person or group does or has done.
Alteration. Any act or process, except repair and light construction as defined herein, that
changes one or more of the architectural features of a structure or site, including, but not limited
to, the erection, construction, reconstruction, relocation of, or addition to a structure. The term
"alteration" may apply to any act or process that changes the interior architectural features of that
portion of a public or private property commonly frequented by the general public, provided said
public or private property is located within a designated historic district or listed individually on
the National Register of Historic Places. However, changes upon interior elements of private
residences, regardless of their location or historic status, are not considered alterations as defined
in this section. The term "alteration" further means any change or addition to a building a
structure within a regulated flood hazard area floodplain that either increases its exterior
horizontal dimensions or increases its potential flood hazard; or means revisions or updates to a
DNRC designated floodplain or floodway established by MCA 76-5-101 et seq.
Appurtenant structure. A structure in which the use is incidental or accessory to a
principal use.
Artificial obstruction/development. Any obstruction which is not natural and includes
any dam, diversion, wall, bank stabilization method, embankment, levee, dike, pile, abutment,
projection, revetment, excavation, channel rectification, road, bridge, conduit, culvert, building,
refuse, automobile body, fill or other analogous structure or matter in, along, across or projecting
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into any regulated flood hazard area that 100-year floodplain which may impede, retard or alter
the pattern of flow of water, either in itself or by catching or collecting debris carried by the
water, or that is placed where the natural flow of water would carry the same downstream to the
damage or detriment of either life or property.
Sec. 38.700.030. – B definitions.
Base flood discharge. The flowrate of a flood having a one percent chance of being
equaled or exceeded in any given year.
Base flood elevation. The elevation above sea level of the base flood in relation to the
city's adopted vertical datum used in a FEMA flood insurance study or a flood hazard
evaluation.vertical datum unless otherwise specified in the flood hazard study.
Basement. A portion of a building located partly underground but having not less than
half its floor-to-ceiling height below the average grade of the adjoining ground. For purposes of
division 38.600, a basement includes any floor elevation that is more than two feet below the
lowest adjacent grade of a building on all sides.
Sec. 38.700.030. – C definitions.
Certified by a professional engineer. Certification of work produced by a duly qualified
and licensed professional engineer through the placement of the professional engineer’s signed
stamp.
Channel. The geographical area within either the natural or artificial banks of a
watercourse or drainway.
Crawlspace. For purposes of division 38.600, a building enclosure that has its interior
floor area no more than five feet below the top of the next highest floor and no more than two
feet below the lowest adjacent grade on all sides.
Sec. 38.700.040. – D definitions.
DNRC. Montana Department of Natural Resources and Conservation.
Development. Any manmade change to improve or alter real estate, including, but not
limited to, subdivision of land, buildings or other structures, artificial obstructions, mining,
dredging, filling, grading, paving, excavation or drilling operations, or storage of equipment or
materials.
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Drainway. Any depression two feet (2’) or more below the surrounding land serving to
give direction to a current of water less than 9 months of the year and having a bed and well-
defined banks. Water flowing in a drainway may originate by natural or manmade means.
Sec. 38.700.050. – E definitions.
Effective base flood elevation. The base flood elevation contained in the effective FEMA
flood insurance study and its effective hydraulic model, including any effective FEMA revisions
thereto.
Effective regulatory floodway. The regulatory floodway contained in the effective FEMA
flood insurance study and its effective hydraulic model, including any effective FEMA revisions
thereto.
Elevated building. A building without a basement that has it lowest elevated floor raised
above ground level by foundation walls, shear walls, posts, piers, pilings or columns. A building
on a crawlspace is considered an elevated building.
Enclosure. That portion below the lowest elevated floor of an elevated building that is
either partially or fully shut in by rigid walls, including a crawlspace, sub grade crawlspace,
stairwell, elevator, or a garage below or attached.
Encroachment. For purposes of division 38.600 any use, activity, or artificial obstruction
within the regulated flood hazard area.
Encroachment analysis. A hydrologic and hydraulic analysis performed by a qualified
professional engineer to assess the effects of a proposed use, activity, or artificial obstruction on
the base flood elevation, flood flows and flood velocities.
Existing artificial obstruction or nonconforming use: For purposes of division 38.600, an
artificial obstruction or nonconforming use that lawfully existed prior to the initial creation of
city floodplain regulations on March 19, 1975, or any repeal and replacement or amendment
thereto.
Existing base flood elevation. The base flood elevation computed by hydraulic modeling
of the base flood discharge within the floodplain of the flooding source in its current existing
condition.
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Existing building or structure. For purposes of division 38.600, any buildings or
structures for which the start of construction commenced before the effective date of the
applicable flood insurance rate map.
Existing regulatory floodway. The regulatory floodway computed by hydraulic modeling
of the base flood discharge within the floodplain of the flooding source in its current existing
condition.
Sec. 38.700.050. – F definitions.
FEMA. Federal Emergency Management Agency.
Flood insurance rate map. The official map used for flood insurance risk ratings and
other regulatory purposes on which FEMA has delineated special flood hazard areas of the base
flood as well as other flood hazard areas. both the 100-year floodplains and the risk premium
zones.
Flood insurance study. The official report containing technical information used to
produce official flood insurance rate maps in which FEMA has provides base flood discharges,
base flood profiles, floodway data tables, hydraulic modeling, and other related flood hazard
information. as well as the Flood Boundary/Floodway Map and the water surface profiles.
Floodway fringe. The portion of the floodplain of the regulated flood hazard area that is
outside the limits of the regulatory floodway.
Flood of 100-year frequency. A flood magnitude that has a 1% chance of occurring in
any given year. The base flood.
Floodplain. Areas generally adjoining a watercourse or drainway stream that would be
covered by the base flood. floodwater of a 100-year flood except for designated shallow flooding
areas that receive less than one foot of water per occurrence. The floodplain is a regulated flood
hazard area and may be partitioned into consists of a regulatory floodway and floodway fringe
where specifically designated. Floodplain regulations are found in article 6 of this chapter.
Floodplain Administrator. Community official with authority to administer and
implement the provisions of division 38.600. The Floodplain Administrator has been designated
by the city commission to be the city engineer, who may delegate Floodplain Administrator
duties to a member of the city engineering division staff.
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Floodproofing. Any combination of structural and non-structural additions, changes, or
adjustments to buildings or structures which reduce or eliminate flood damage to real estate or
improved real property, water and sanitary facilities, and building or structure contents.
Sec. 38.700.110. – L definitions.
Letter of map change. An official response from FEMA upon review of an application to
amend or revise the FEMA special flood hazard area or flood insurance study for purposes of
flood insurance ratings or flood hazard determinations. FEMA letters of map change include:
(a) Letter of map amendment. A letter of determination from FEMA that amends the
special flood hazard area where a building or a portion of property is situated upon
natural ground that is higher than the base flood elevation and is thus not subject to
mandatory flood insurance.
(b) Letter of map revision based on fill. – A letter of determination from FEMA that
revises the special flood hazard area on a property based on the placement of sufficient
quantities of fill to elevate the property or portion thereof above the base flood elevation.
A building placed on fill must have its lowest floor, including the bottom of a crawlspace,
above the base flood elevation to avoid mandatory flood insurance.
(c) Letter of map revision - floodway. A letter of determination from FEMA that revises
the special flood hazard where a building or a portion of property is located on natural
ground that is higher than the base flood elevation and has been inadvertently located
within the regulatory floodway and is thus not subject to mandatory flood insurance.
(d) Letter of map revision. An official FEMA revision to the effective flood insurance
study and flood insurance rate map incorporating physical changes to the floodplain that
alter the base flood elevation and location of special flood hazard areas.
Lowest Floor. Any floor of a building including a basement used for living purposes,
storage, or recreation. This includes any floor that could be converted to such a use.
Sec. 38.700.120. – M definitions.
Maintenance. For purposes of division 38.600, customary and historical cleaning and
removal of accumulated silt, branches, trees, sticks and other debris as well as minor repair or
restoration activities of existing buildings, structures or artificial obstructions to the size, shape,
position and height existing immediately prior to deterioration that are not substantial
improvements.
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Sec. 38.700.130. – N definitions.
Natural Ground. The elevation of the ground surface existing at the time an area
becomes located within a FEMA special flood hazard shown on the effective flood insurance rate
that remains unaffected by construction techniques such as placement of fill, landscaping, and
berms.
No-rise. A technical analysis conducted in accordance with FEMA procedures and
certified by a qualified professional engineer that shows a proposed use, activity or artificial
obstruction located in the regulatory floodway causes a rise of no more than 0.00 feet to the
existing base flood elevation.
Non-residential buildings or structures. Buildings or structures that are not used for
residential purposes including commercial, industrial, institutional, agricultural and accessory
buildings or structures, and manufactured homes used for non-residential purposes.
Sec. 38.700.140. – O definitions.
Official floodplain maps. The flood insurance rate maps (FIRMs) and flood insurance
study (FIS) provided by the Federal Emergency Management Agency (FEMA) for the Gallatin
County, Montana, inclusive of the City of Bozeman, dated April 21, 2021 September 2, 2011
(FEMA FISFlood Insurance Study No. 30031CV001B 30031CV000A), and incorporating any
approved updates or revisions letters of map change listed pursuant to Sec. 38.600.110.A.1.
Owner. For purposes of division 38.600 an owner is any person or entity that has
dominion over, control of, or title to an artificial obstruction.
Sec. 38.700.160. – R definitions.
Recreational vehicle. A vehicular-type portable structure without permanent foundation,
which is built on a single chassis; which is 400 square feet or less when measured at the largest
horizontal projection; which is designed to be self-propelled or permanently towable by a light-
duty truck; which is primarily designed not for use as a permanent dwelling but as temporary
living accommodations for recreational, camping and travel use and including, but not limited to,
travel trailers, truck campers, camping trailers and self-propelled motor homes less than eight
feet in width and 50 feet in length.
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Regulated flood hazard area. Land area which has been specifically identified in Sec.
38.600.110 as subject to base flood hazards, which may consist of the special flood hazard area,
regulatory floodway, and flood fringe where specifically designated.
Regulatory floodway. That portion of the special flood hazard area designated by FEMA
in the official flood insurance study and flood insurance rate maps as being the regulatory
floodway that must be reserved in order to discharge the base flood without cumulatively
increasing the base flood elevation more than one half foot (0.5 feet).
Residential building. A building used as a permanent dwelling for human habitation.
Riprap. Stone, rocks, concrete blocks, or analogous materials that are placed along the
bed or banks of a watercourse or drainway for the purpose of preventing or alleviating erosion.
Sec. 38.700.170. – S definitions.
Scour depth. The maximum depth of streambed scour caused by erosive forces of the
base flood. Scour may be categorized as localized or general depending upon its location and
proximity to artificial obstructions.
Special Flood Hazard Area. Land area which has been specifically identified by FEMA
on a flood insurance rate map as being subject to the base flood. The special flood hazard area
contains the regulatory floodway. Any building with a federally backed loan located in the
special flood hazard is mandated by federal law to carry flood insurance.
Start of Construction. The commencement of clearing, grading, filling or excavating to
prepare a site for construction, and for purposes of division 38.600 start of construction includes
substantial improvement, and means the date the building permit was issued, provided the actual
start of construction, repair, reconstruction, rehabilitation, addition 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 foundations 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. For a substantial improvement, the actual start of construction
means the first alteration of any wall, ceiling, floor, or other structural part of a building, whether
or not that alteration affects the external dimensions of the building.
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Substantial damage. For purposes of division 38.600, damage of any origin sustained by
a building or structure whereby the cost of restoring the building or structure to its before
damaged condition would equal or exceed fifty percent (50%) of the market value of the building
or structure before the damage occurred.
Suitable fill. Fill material which is stable, compacted, well graded, and pervious; not
adversely affected by water and frost; devoid of trash or similar foreign matter, tree stumps or
other organic material; and is fitting for the purpose of supporting the intended use, building, or
structure.
Sec. 38.700.170. – T definitions.
Temporary protective measures. A use, activity, or artificial obstruction that is readily
implemented upon commencement of a flooding emergency for the purpose of protecting
existing buildings, structures, and life safety that is not located in the channel of the regulatory
floodway and is readily removed upon cessation of the flooding emergency.
Section 7
CHAPTER 2, ARTICLE 2 – BOZEMAN CREEK be amended as follows with all remaining
text remaining as is:
Sec. 42.02.010. - Channel to be kept free from obstructions. Reserved
The channel of Bozeman Creek, throughout its course within the corporate limits of the city,
shall be preserved and kept at a minimum width of 12 feet in the clear, and kept free of all
obstruction unless and until it shall be otherwise ordered or permitted by the city commission by
ordinance or resolution duly adopted.
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Ordinance 2057, Amending Floodplain Regulations of the Bozeman Municipal Code
Page 58 of 59
Sec. 42.02.020. - Narrowing, turning or obstructing channel prohibited; exception. Reserved.
Any person, firm, corporation or association who, directly or indirectly, or by any means
whatever or at all confines Bozeman Creek, in any part of its course through the corporate limits
of the city, to a narrower channel than is prescribed in section 42.02.010; or who alters, changes
or turns the same from its natural channel, or alters its course at any point within the corporate
limits of the city, except in pursuance of and in accordance with an ordinance or resolution of the
city commission duly passed and adopted; or who builds, throws, deposits or, in any manner or
at all, places any obstruction in the channel of the creek within the corporate limits of the city,
shall be deemed guilty of a violation of this article.
Section 8
Repealer.
All provisions of the ordinances of the City of Bozeman in conflict with the provisions of
this ordinance are, and the same are hereby, repealed and all other provisions of the ordinances of
the City of Bozeman not in conflict with the provisions of this ordinance shall remain in full force
and effect.
Section 9
Savings Provision.
This ordinance does not affect the rights and duties that matured, penalties that were
incurred or proceedings that were begun before the effective date of this ordinance. All other
provision of the Bozeman Municipal Code not amended by this Ordinance shall remain in full
force and effect.
Section 10
Severability.
That should any sentence, paragraph, subdivision, clause, phrase or section of this
ordinance be adjudged or held to be unconstitutional, illegal, or invalid, the same shall not affect
the validity of this ordinance as a whole, or any part or provision thereof, other than the part so
decided to be invalid, illegal or unconstitutional, and shall not affect the validity of the Bozeman
Municipal Code as a whole.
Section 11
Codification.
The provisions of Section 1 through Section 7 shall be codified as appropriate in the
Bozeman Municipal Code. All references within the Bozeman Municipal Code shall be revised to
reflect the changes in this ordinance.
Section 12
Effective Date.
This ordinance shall be in full force and effect on April 21, 2021.
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Ordinance 2057, Amending Floodplain Regulations of the Bozeman Municipal Code
Page 59 of 59
PROVISIONALLY ADOPTED by the City Commission of the City of Bozeman,
Montana, on first reading at a regular session held on the 23rd day of February, 2021.
____________________________________
Cynthia L. Andrus
Mayor
ATTEST:
_________________________________
Mike Maas
City Clerk
FINALLY PASSED, ADOPTED, AND APPROVED by the City Commission of the
City of Bozeman, Montana on second reading at a regular session thereof held on the 9th day of
March, 2021.
____________________________________
Cynthia L. Andrus
Mayor
ATTEST:
_______________________________
Mike Maas
City Clerk
APPROVED AS TO FORM:
____________________________________
Greg Sullivan
City Attorney
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