CHAPTER 11
CITY OF NORTHGLENN ZONING ORDINANCE

ARTICLE 52
REGULATIONS TO MINIMIZE FLOOD LOSSES

Section 11-52-1. Title. This Ordinance shall be known as the Northglenn Flood Hazard Ordinance.

[Source: Ord. 1477, 2007]

Section 11-52-2. Explanation of Public Concern. Based upon the several flood hazard studies undertaken within the current boundaries of the City of Northglenn, nationwide experience with flood waters, and field observations made in the City, the following conclusions are made.

(a)

Hazards Defined. The flood hazard areas of Northglenn are subject to periodic inundation which could result in loss of life and property, health and safety hazards, disruption of commerce and governmental services, extraordinary public expenditures for flood protection and relief, and impairment of the tax base, all of which adversely affect the public health, safety and general welfare.

(b)

Causes. These flood losses are caused by the cumulative effect of obstructions in areas of special flood hazards which increase flood heights and velocities, and when inadequately anchored, damage property in other areas. Structures that are inadequately floodproofed, elevated or otherwise protected from flood damage also contribute to the flood loss.

[Source: Ord. 1477, 2007]

Section 11-52-3. Purpose. The purpose of this Ordinance is to promote the public health, safety, and general welfare, to minimize public and private flood losses in areas subject to flood hazards, and to promote wise use of flood hazard areas. To accomplish its purposes, this Ordinance includes provisions intended to:

(a)

Protect human life and health;

(b)

Minimize expenditure of public money for costly flood control projects;

(c)

Minimize the need for rescue and relief efforts associated with flooding and usually undertaken at public expense;

(d)

Minimize business interruptions;

(e)

Minimize damage to public facilities and utilities located in areas of special flood hazard;

(f)

Help maintain a stable tax base by providing for the prudent use and development of areas of special flood hazard so as to minimize future flood blight areas;

(g)

Ensure that potential buyers are notified that property is in an area of special flood hazard; and

(h)

Ensure that those who occupy areas of special flood hazard assume responsibility for their actions.

[Source: Ord. 1477, 2007]

Section 11-52-4. Definitions.

(a)

100-Year Flood means a flood having a recurrence interval that has a one-percent chance of being equaled or exceeded during any given year (1-Percent-Annual-Chance Flood). The terms "one-hundred-year-flood" and "one percent chance flood" are synonymous with the term "100-Year Flood." The term does not imply that the flood will necessarily happen once every one hundred years.

(b)

100-Year Floodplain means the area of land susceptible to being inundated as a result of the occurrence of a one-hundred-year flood.

(c)

500-Year Flood means a flood having a recurrence interval that has a 0.2-percent chance of being equaled or exceeded during any given year (0.2-percent-annual-chance flood). The term does not imply that the flood will necessarily happen once every five hundred years.

(d)

500-Year Floodplain means the area of land susceptible to being inundated as a result of the occurrence of a five-hundred-year flood.

(e)

Addition means any activity that expands the enclosed footprint or increases the square footage of an existing structure.

(f)

Appeal means a request for a review by the Board of Adjustment of the floodplain administrator's interpretation of any provision of this Ordinance or a request for a variance.

(g)

Base Flood Elevation (BFE) means the elevation shown on a FEMA Flood Insurance Rate Map for zones AE, AH, A1-A30, AR, AR/A, AR/AE, AR/A1-A30, AR/AH, AR/AO, V1-V30, and VE that indicates the water surface elevation resulting from a flood that has a one percent chance of equaling or exceeding that level in any given year.

(h)

Basement means any area of the building having its floor sub-grade (below ground level) on all sides.

(i)

Conditional Letter of Map Revision (CLOMR) means FEMA's comment on a proposed project, which does not revise an effective floodplain map, that would, upon construction, affect the hydrologic or hydraulic characteristics of a flooding source and thus result in the modification of the existing regulatory floodplain.

(j)

Critical Facility means a structure or related infrastructure, but not the land on which it is situated, as specified in the provisions for flood hazard reduction, that if flooded may result in significant hazards to public health and safety or interrupt essential services and operations for the community at any time before, during and after a flood.

(k)

Development means any man-made change to improved or unimproved real estate, including but not limited to buildings or other structures, mining, dredging, filling, grading, paving, excavation, or drilling operations or storage of equipment, vehicles or materials located within the Area of Special Flood Hazard.

(l)

Development Permit means for the purposes of this ordinance only, an application to the floodplain administrator on forms supplied by the floodplain administrator, for permission to develop land and/or construct any structure within any area of special flood hazard.

(m)

DFIRM Database means a database (usually spreadsheets containing data and analyses that accompany DFIRMS). The FEMA mapping specifications and guidelines outline requirements for the development and maintenance of DFIRM databases.

(n)

Digital Flood Insurance Rate Map (DFIRM) means the FEMA Digital Floodplain Map. These digital maps serve as "regulatory floodplain maps" for insurance and floodplain management purposes.

(o)

Elevated Building means a non-basement building (I) built in the case of a building in zones A1-30, AE, A, A99, AO, AH, B, C, X, and D, to have the top of the elevated floor, above the ground level by means of pilings, columns (posts and piers), or shear walls parallel to the flow of the water; and (II) adequately anchored so as not to impair the structural integrity of the building during a flood of up to the magnitude of the base flood. In the case of zones A1-30, AE, A, A99, AO, AH, B, C, X, and D, "Elevated Building" also includes a building elevated by means of fill or solid foundation perimeter walls with openings sufficient to facilitate the unimpeded movement of flood waters.

(p)

FEMA means the Federal Emergency Management Agency, the agency responsible for administering the National Flood Insurance Program.

(q)

Flood or flooding means a general and temporary condition of partial or complete inundation of normally dry land areas from:

(1)

the overflow of water from channels and reservoir spillways;

(2)

the unusual and rapid accumulation or runoff of surface waters from any source; or

(3)

mudslides or mudflows that occur from excess surface water that is combined with mud or other debris that is sufficiently fluid so as to flow over the surface of normally dry land areas (such as earth carried by a current of water and deposited along the path of the current).

(r)

Flood Insurance Rate Map (FIRM) means the official map on which the Federal Emergency Management Agency has delineated both the areas of special flood hazards and the risk premium zones applicable to the community.

(s)

Flood Insurance Study (FIS) means the official report entitled, the Flood Insurance Study for Adams County, Colorado and Incorporated Areas, dated January 20, 2016, with accompanying flood insurance rate maps and/or flood boundary floodway maps (FIRM and/or FBFM) in which the Federal Emergency Management Agency has provided flood profiles, the Floodway Map, and the water surface elevation of the base flood, and any subsequent additions, updates, revisions or modifications to said study.

(t)

Floodplain or Flood-prone Area means any land area susceptible to being inundated by water from any source (See definition of flooding).

(u)

Flood profile is a graph of a longitudinal profile showing the relationship of the water surface elevation of a flood event to location along a stream or river.

(v)

Flood proofing is a combination of structural and non-structural additions, provisions, changes, or adjustments to properties and structures subject to flooding primarily for the reduction or elimination of flood damage to properties, water and sanitary facilities, structures, and contents of buildings in a flood hazard area.

(w)

Floodway (Regulatory Floodway) means the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the 100-year flood without cumulatively increasing the water surface elevation more than a designated height. The Colorado statewide standard for the designated height to be used for all newly studied reaches shall be one-half foot (six inches). Letters of map revision to existing floodway delineations may continue to use the floodway criteria in place at the time of the existing floodway delineation.

(x)

Floodway and Floodplain Zoning Administrator is the City Manager of the City of Northglenn or the City Manager's authorized representative.

(y)

Freeboard means the vertical distance in feet above a predicted water surface elevation intended to provide a margin of safety to compensate for unknown factors that could contribute to flood heights greater than the height calculated for a selected size flood such as debris blockage of bridge openings and the increased runoff due to urbanization of the watershed.

(z)

Highest Adjacent Grade means the highest natural elevation of the ground surface prior to construction next to the proposed walls of a structure.

(aa)

Historic Structure means any structure that is:

(1)

Listed individually in the National Register of Historic Places (a listing maintained by the Department of the Interior) or preliminarily determined by the Secretary of the Interior as meeting the requirements for individual listing on the National Register;

(2)

Certified or preliminarily determined by the Secretary of the Interior as contributing to the historical significance of a registered historic district or a district preliminarily determined by the Secretary to qualify as a registered historic district;

(3)

Individually listed on a state inventory of historic places in states with historic preservation programs which have been approved by the Secretary of the Interior; or

(4)

Individually listed on a local inventory of historic places in communities with historic preservation programs that have been certified either:

(A)

By an approved state program as determined by the Secretary of the Interior; or

(B)

Directly by the Secretary of the Interior in states without approved programs.

(bb)

Letter of Map Revision (LOMR) means FEMA's official revision of an effective flood insurance rate map (FIRM), or flood boundary and floodway map (FBFM), or both. LOMRs are generally based on the implementation of physical measures that affect the hydrologic or hydraulic characteristics of a flooding source and thus result in the modification of the existing regulatory floodway, the effective base flood elevations (BFEs), or the special flood hazard area (SFHA).

(cc)

Letter of Map Revision Based on Fill (LOMR-F) means FEMA's modification of the special flood hazard area (SFHA) shown on the flood insurance rate map (FIRM) based on the placement of fill outside the existing regulatory floodway.

(dd)

Lowest Floor means the lowest floor of the lowest enclosed area (including basement). Any floor used for living purposes which includes working, storage, sleeping, cooking and eating, or recreation or any combination thereof. This includes any floor that could be converted to such a use such as a basement or crawl space. The lowest floor is a determinate for the flood insurance premium for a building, home or business. An unfinished or flood resistant enclosure, usable solely for parking or vehicles, building access or storage in an area other than a basement area is not considered a building's lowest floor; provided that such enclosure is not built so as to render the structure in violation of the applicable non-elevation design requirements of Section 60.3 of the National Flood Insurance Program Regulations.

(ee)

Manufactured Home means a structure, transportable in one or more sections, which is built on a permanent chassis and is designed for use with or without a permanent foundation when connected to the required utilities. This term also includes park trailers, travel trailers, and other similar vehicles placed on a site for greater than 180 consecutive days. The term "Manufactured Home" does not include a "Recreational Vehicle".

(ff)

Manufactured Home Park or Subdivision means a parcel (or contiguous parcels) of land divided into two or more manufactured home lots for rent or sale.

(gg)

Mean Sea Level means the National Geodetic Vertical Datum (NGVD) of 1929 or other datum, to which base flood elevations are referenced.

(hh)

National Flood Insurance Program (NFIP) means FEMA's program of flood insurance coverage and floodplain management administered in conjunction with the Robert T. Stafford Relief and Emergency Assistance Act. The NFIP has applicable federal regulations promulgated in Title 44 of the Code of Federal Regulations. The U.S. Congress established the NFIP in 1968 with the passage of the National Flood Insurance Act of 1968.

(ii)

New Construction means structures for which the start of construction commenced on or after the effective date of this Ordinance, as amended.

(jj)

No-rise Certification means a record of the results of an engineering analysis conducted to determine whether a project will increase flood heights in a floodway. A no-rise certification must be supported by technical data and signed by a registered Colorado professional engineer. The supporting technical data should be based on the standard step-backwater computer model used to develop the 100-year floodway shown on the flood insurance rate map (FIRM) or flood boundary and floodway map (FBFM).

(kk)

Obstruction means sandbars formed by the natural flow of a watercourse, temporary structure, planks, snags, and debris in and along an existing channel which cause a flood hazard.

(ll)

Physical Map Revisions (PMR) means FEMA's action whereby one or more map panels are physically revised and republished. A PMR is used to change flood risk zones, floodplain, and/or floodway delineations, flood elevations, and/or planimetric features.

(mm)

Recreational Vehicle means a vehicle which is:

(1)

Built on a single chassis;

(2)

400 square feet or less when measured at the largest horizontal projection;

(3)

Designed to be self-propelled or permanently towable by a light duty truck; and

(4)

Designed primarily not for use as a permanent dwelling but as temporary living quarters for recreational, camping, travel or seasonal use.

(nn)

Special Flood Hazard Area means the land in the floodplain within a community subject to a one percent or greater chance of flooding in any given year, i.e., the 100-year floodplain.

(oo)

Start of Construction means and 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 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.

(pp)

Structure means a walled and roofed building or manufactured home, or a gas or liquid storage tank that is principally above ground.

(qq)

Substantial Damage means damage of any origin sustained by a structure whereby the cost of restoring the structure to its before damaged condition would equal or exceed 50 percent of the market value of the structure before the damage occurred.

(rr)

Substantial Improvement means any repair, reconstruction, or improvement to a structure, the cost of which equals or exceeds 50 percent of the market value of the structure either:

(1)

Before the improvement or repair is started; or

(2)

If the structure has been damaged and is being restored, before the damage occurred.

This term does not, however, include any project for improvement of a structure to comply with existing state or local health, sanitary, or safety code specifications which are necessary to assure a safe living condition. Nor shall this term include any alteration of a structure listed on the National Register of Historic Places or a state inventory of historic places, provided that the alteration will not preclude the structure's continued designation of a "historic structure".

(ss)

Threshold Planning Quantity (TPQ) means a quantity designated for each chemical on the list of extreme hazardous substances that triggers notification by facilities to the state that such facilities are subject to emergency planning requirements.

(tt)

Variance means a grant by the Board of Adjustment of relief from the requirements of this Ordinance which permits construction in a manner that would otherwise be prohibited by this Ordinance.

(uu)

Violation means the failure of a structure or other development to be fully compliant with the community's floodplain management regulations. A structure or other development without the elevation certificate, other certifications, or other evidence of compliance required in Section 60.3(b)(5), (c)(4), (c)(10), (d)(3), (e)(2), (e)(4), or (e)(5) of the National Flood Insurance Regulations is presumed to be in violation until such time as that documentation is provided.

(vv)

Water Surface Elevation means the height, in relation to the National Geodetic Vertical Datum (NGVD) of 1929 (or other datum, where specified), of floods of various magnitudes and frequencies in the floodplains of coastal or riverine areas.

[Source: Ord. 1477, 2007; 1662, 2013; 1708, 2015]

Section 11-52-5. General Provisions.

(a)

Jurisdiction. This Article 52 shall apply to all areas of special flood hazard and areas removed from the floodplain by the issuance of a FEMA letter of map revision based on fill (LOMR-F) within the jurisdiction of the City of Northglenn.

(b)

Basis for Establishing Areas of Special Flood Hazard. The Federal Emergency Management Agency has identified the areas of special flood hazard in the Flood Insurance Study for Adams County, Colorado and Incorporated Areas, dated January 20, 2016, with accompanying flood insurance rate maps and/or flood boundary floodway maps (FIRM and/or FBFM), and this study and accompanying Flood Insurance Rate Maps, are hereby adopted by reference and declared to be a part of this Ordinance. For the purpose of final determination of the areas of special flood hazard, the flood profile shall control. The Flood Insurance Study and the Flood Insurance Rate Maps are on file in the Department of Public Works.

(c)

Establishment of Floodplain Development Permit. A development permit shall be required to ensure conformance with the provisions of this Article.

(d)

Compliance. No structure or land shall hereafter be located, altered, or have its use changed without full compliance with the terms of this Article and other applicable regulations.

(e)

Abrogation and Greater Restrictions. This Article is not intended to repeal, abrogate, or impair any existing easements, covenants, or deed restrictions. However, where this Article and another ordinance, easement, covenant, or deed restriction conflict or overlap, whichever imposes the more stringent restrictions shall prevail.

(f)

Interpretation. In the interpretation and application of this Ordinance, all provisions shall be:

(1)

Considered as minimum requirements;

(2)

Liberally construed in favor of the governing body; and

(3)

Deemed neither to limit nor repeal any other powers granted under state statutes.

(g)

Warning and Disclaimer of Liability. The degree of flood protection required by this Article 52 is considered reasonable for regulatory purposes and is based upon engineering and scientific methods of study. Larger floods may occur on occasions or the flood height may be increased by manmade or natural causes. This Ordinance does not imply that land outside areas of special flood hazard or land uses permitted within such areas will always be totally free from flooding or flood damages. Nor shall this Section create a liability on the part of, or create a cause of action against the City of Northglenn or any officer or employee thereof, or the Federal Emergency Management Agency, for any flood damages that may result from reliance on this Ordinance or any administrative decision lawfully made thereunder.

[Source: Ord. 1477, 2007; 1662, 2013; 1708, 2015]

Section 11-52-6. Administration.

(a)

Designation of Administrator. The City Manager, or the City Manager's authorized representative shall be the floodplain administrator and shall administer, interpret, and implement this ordinance by granting or denying development permit applications in accordance with its provisions.

(b)

Duties of the Administrator. The duties of the floodplain administrator shall include, but not be limited to:

(1)

Review of all development permits to insure that the permit requirements of this Ordinance have been satisfied;

(2)

Review of all development permits to insure that all necessary permits have been obtained from which prior approval is required, including, but not limited to, Federal and/or State law including Section 404 of the Federal Water Pollution Control Act amendments of 1972, 33 U.S.C. 1334;

(3)

Review of all development permits to determine if the proposed development is located in the floodway. If located in the floodway, assure that the encroachment provisions of Section 11-52-10 are met.

(4)

Review of all development permits to determine that all such proposals are consistent with the need to minimize flood damage within the flood-prone area, that all public facilities and utilities such as sewer, gas, electrical and water systems are located and constructed to minimize or eliminate flood damage and to assure that adequate drainage is provided to reduce exposure to flood hazards.

(5)

Obtain and record the elevation in Mean Sea Level of the lowest floor, including basement, of any new or substantially improved structures located in a special flood hazard area, and whether or not the structure includes a basement.

(6)

For all new or substantially improved floodproofed structures located in a special flood hazard area:

(A)

Require that a professional engineer or architect licensed in the State of Colorado develop and/or review all structural design specifications and plans for such structures.

(B)

Verify and record the actual elevation, in Mean Sea Level, to which the structure has been floodproofed.

(C)

Maintain the floodproofing certifications required in Section 11-52-6(d)(4) of this Ordinance.

(7)

Maintain for public inspection all records pertaining to the provisions of this Ordinance.

(8)

Notify adjacent communities and the Colorado Water Conservation Board prior to any alteration or relocation of a watercourse, and submit evidence of such notification to the Federal Emergency Management Agency.

(9)

Require that maintenance is provided within the altered or relocated portion of a watercourse so that the flood carrying capacity is not diminished.

(10)

Review of State and Federal regulations related to the National Flood Insurance Program and to maintain this ordinance in compliance with those regulations through periodic updates and revisions.

(c)

Alternate Sources of Data. When base flood elevation data has not been provided in accordance with Section 11-52-5(b), the flood plain administrator shall obtain, review and reasonably utilize any base flood elevation and floodway data available from Federal, State, or other source as criteria for requiring that new construction, substantial improvement, or other development in any area of special flood hazard of the Flood Insurance Rate Map is administered in accordance with Section 11-52-9.

(d)

Development Permit Required. A development permit shall be obtained before construction or development begins within any area of special flood hazard. Application for a development permit shall be made on forms furnished by the floodplain administrator and may include, but not be limited to: plans drawn to scale showing the nature, location, dimensions, and elevations of the area in question; existing or proposed structures; fill; storage of materials outside; drainage facilities; and the location of the foregoing. Specifically, the following information is required:

(1)

Base flood elevation data in relation to the land surface that is proposed for development.

(2)

Elevation in relation to Mean Sea Level of the lowest floor (including basement) of all new and substantially improved structures.

(3)

Elevation in relation to Mean Sea Level to which any structure has been floodproofed.

(4)

Certification by a registered professional engineer or architect licensed in the State of Colorado that the construction or development complies with all requirements of this Article 52.

(5)

Description of the extent to which any watercourse will be altered or relocated as a result of proposed development.

(6)

All necessary permits for which prior approval may be required, including, but not limited to, any applicable Federal and/or State law.

(e)

Approval or denial of a development permit by the floodplain administrator shall be based on all of the provisions of this Ordinance and the following relevant factors:

(1)

The danger to life and property due to flooding or erosion damage;

(2)

The susceptibility of the proposed facility and its contents to flood damage and the effect of such damage on the individual owner;

(3)

The danger that materials may be swept onto other lands to the injury of others;

(4)

The compatibility of the proposed use with existing and anticipated development;

(5)

The safety of access to the property in times of flood for ordinary and emergency vehicles;

(6)

The costs of providing governmental services during and after flood conditions including maintenance and repair of streets and bridges, and public utilities and facilities such as sewer, gas, electrical and water systems;

(7)

The expected heights, velocity, duration, rate of rise and sediment transport of the flood waters and the effects of wave action, if applicable, expected at the site;

(8)

The necessity to the facility of a waterfront location, where applicable;

(9)

The availability of alternative locations, not subject to flooding or erosion damage, for the proposed use; and

(9)

The relationship of the proposed use to the comprehensive plan for that area.

(f)

Mapping Disputes. The floodplain administrator shall make interpretations, where needed, as to the exact location of the boundaries of the areas of special flood hazards. The Board of Adjustment shall decide cases in which a boundary is disputed, according to the provisions for appeal contained in Section 11-52-11.

[Source: Ord. 1477, 2007; 1662, 2013; 1708, 2015]

Section 11-52-7. New Subdivisions. An application for a new subdivision pursuant to Chapter 12 of the Northglenn Municipal Code shall include the submittal of an application for a development permit under this Article 52 showing the following:

(a)

That the design of the new land subdivisions (not including resubdivisions) in a special flood hazard area is consistent with the need to minimize flooding;

(b)

That public utilities and facilities are located and constructed to minimize flood damage;

(c)

That adequate drainage is provided to reduce exposure to flood damage; and

(d)

That base flood elevation data is provided.

[Source: Ord. 1477, 2007; 1662, 2013]

Section 11-52-8. Construction Standards -- All Flood Hazard Areas.

(a)

Application. The following standards are required for all new construction and substantial improvements in all special flood hazard areas.

(b)

Anchoring.

(1)

All new construction and substantial improvements shall be anchored to prevent flotation, collapse or lateral movement of the structure and to withstand hydrostatic and hydrodynamic loads including the effects of bouyancy.

(2)

All manufactured homes must be elevated and anchored to resist flotation, collapse, lateral movement, and hydrostatic and hydrodynamic loads. Methods of anchoring may include, but are not limited to use of over-the-top or frame ties to ground anchors. This requirement is in addition to applicable state and local anchoring requirements for resisting wind forces.

(A)

Any additions to the manufactured home shall be similarly anchored.

(c)

Construction Materials and Methods.

(1)

All new construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage.

(2)

All new construction and substantial improvements shall be constructed using methods and practices that minimize flood damage, including anchoring to resist flotation and lateral movement.

(3)

All new construction and substantial improvements that have fully enclosed areas below the lowest floor that are used solely for parking of vehicles, building access or storage in an area other than a basement and which are subject to flooding shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs for meeting this requirement must either be certified by a registered professional engineer or architect licensed in the State of Colorado, or meet or exceed the following minimum criteria: a minimum of two openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding shall be provided. The bottom of all openings shall be no higher than one foot above grade. openings may be equipped with screens, louvers, valves, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters.

(d)

Utilities.

(1)

All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of floodwaters into the system.

(2)

New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwater into the system and discharges from the system into floodwaters.

(3)

On-site waste disposal systems shall be located to avoid impairment to them or contamination from them during flooding.

(4)

Electrical, heating, ventilation, plumbing, and air-conditioning equipment and other service facilities shall be designed and/or located so as to prevent floodwater from entering or accumulating within the components.

[Source: Ord. 1477, 2007]

Section 11-52-9. Construction Standards Where Base Flood Elevation is Provided.

(a)

Application. In all areas of special flood hazard where base flood elevation data has been provided as set forth in Section 11-52-5(b), Basis For Establishing Areas of Special Flood Hazard, or Section 11-52-6(c), Alternate Sources of Data, the following standards are required.

(b)

Residential Construction. New construction and substantial improvement of any residential structure shall have the lowest floor (including basement) electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities (including ductwork), elevated to one (1) foot above the base flood elevation. A registered professional engineer, architect, or land surveyor shall submit a certification to the floodplain administrator that the standard of this subsection is satisfied.

(c)

Nonresidential Construction. New construction or substantial improvement of any nonresidential structure shall either have the lowest floor (including basement) elevated to the level of the base flood elevation, or together with attendant utility and sanitary facilities, shall:

(1)

Be floodproofed so that the structure is watertight one (1) foot above the base flood elevation with walls substantially impermeable to the passage of water;

(2)

Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy.

(d)

Manufactured Homes. All manufactured homes erected, installed, or substantially improved within zones A1-30, AH, and AE on the community's FIRM on sites outside of a manufactured home park or subdivision shall be elevated and anchored on a permanent foundation such that the lowest floor of the manufactured home, electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities (including ductwork), be elevated to one foot above the base flood elevation.

[Source: Ord. 1477, 2007; 1662, 2013]

Section 11-52-10. Floodway Restrictions.

(a)

No encroachment, including fill, new construction, substantial improvement, or other development shall be permitted in the Floodway as defined in Section 11-52-4(K), unless certification consistent with the requirements of 44 CFR 59-78, by a professional engineer or architect licensed in the State of Colorado is provided demonstrating that encroachment will not result in any increase in flood levels during occurrence of the base flood.

(b)

All new construction or substantial improvements in the floodway shall comply with all applicable construction standards of Sections 11-52-8 and 11-52-9.

(c)

All new construction and substantial improvements in zones AH and AO of the special flood hazard areas shall have adequate drainage paths around structures on slopes to guide floodwaters around and away from the proposed structures.

(d)

All recreational vehicles placed on sites within zones A1-30, AH and AE shall conform with one of the following conditions:

(1)

Be on the site for fewer than 180 consecutive days,

(2)

Be fully licensed and ready for highway use, or

(3)

Meet the permit requirements of this Article 52 and the elevation and anchoring requirements for "Manufactured Homes" of this Article 52.

A recreational vehicle is ready for highway use if it is on its wheels or jacking system, is attached to the site only by quick disconnect type utilities and security devices, and has no permanently attached additions.

(e)

Under the provisions of 44 CFR Chapter 1, Section 65.12 of the National Flood Insurance Regulations, the City may permit encroachments within the adopted regulatory floodway that would result in an increase in base flood elevations, provided that the community first applies for a CLOMR and floodway revision through FEMA.

[Source: Ord. 1477, 2007; 1662, 2013]

Section 11-52-11. Alteration of a Watercourse. For all proposed developments that alter a watercourse within a special flood hazard area, the following standards apply:

(a)

Channelization and flow diversion projects shall appropriately consider issues of sediment transport, erosion, deposition, and channel migration, and properly mitigate potential problems through the project as well as upstream and downstream of any improvement activity. A detailed analysis of sediment transport and overall channel stability should be considered, when appropriate, to assist in determining the most appropriate design.

(b)

Channelization and flow diversion projects shall evaluate the residual 100-year floodplain.

(c)

Any channelization or other stream alteration activity proposed by a project proponent must be evaluated for its impact on the regulatory floodplain and be in compliance with all applicable federal, state and local floodplain rules, regulations and ordinances.

(d)

Any stream alteration activity shall be designed and sealed by a registered Colorado professional engineer or certified professional hydrologist.

(e)

All activities within the regulatory floodplain shall meet all applicable federal, state and city floodplain requirements and regulations.

(f)

Within the regulatory floodway, stream alteration activities shall not be constructed unless the project proponent demonstrates through a floodway analysis and report, sealed by a registered Colorado professional engineer, that there is not more than a 0.00-foot rise in the proposed conditions compared to existing conditions floodway resulting from the project, otherwise known as a no-rise certification, unless the community first applies for a CLOMR and floodway revision in accordance with the provisions of this Article 52.

(g)

Maintenance shall be required for any altered or relocated portions of watercourses so that the flood-carrying capacity is not diminished.

[Source: Ord. 1477, 2007; 1662, 2013]

Section 11-52-12. Properties Removed from the Floodplain by Fill. A floodplain development permit shall not be issued for the construction of a new structure or addition to an existing structure on a property removed from the floodplain by the issuance of a FEMA letter of map revision based on fill (LOMR-F), unless such new structure or addition complies with the following:

(a)

Residential Construction. The lowest floor (including basement), electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities (including ductwork), must be elevated to one foot above the base flood elevation that existed prior to the placement of fill.

(b)

Nonresidential Construction. The lowest floor (including basement), electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities (including ductwork), must be elevated to one foot above the base flood elevation that existed prior to the placement of fill, or together with attendant utility and sanitary facilities be designed so that the structure or addition is watertight to at least one foot above the base flood level that existed prior to the placement of fill with walls substantially impermeable to the passage of water and with structural components having the capability of resisting hydrostatic and hydrodynamic loads of effects of buoyancy.

[Source: Ord. 1477, 2007; 1662, 2013]

Section 11-52-13. Standards for Critical Facilities. A critical facility is a structure or related infrastructure, but not the land on which it is situated, as specified in Rule 6 of the Rules and Regulations for Regulatory Floodplains in Colorado, that if flooded may result in significant hazards to public health and safety or interrupt essential services and operations for the community at any time before, during and after a flood.

(a)

Classification of Critical Facilities. It is the responsibility of the City Council to identify and confirm that specific structures in their community meet the following criteria:

(b)

Critical facilities are classified under the following categories: (1) essential services; (2) hazardous materials; (3) at-risk populations; and (4) vital to restoring normal services.

(1)

Essential services facilities include public safety, emergency response, emergency medical, designated emergency shelters, communications, public utility plant facilities, and transportation lifelines.

These facilities consist of:

(A)

Public safety (police stations, fire and rescue stations, emergency vehicle and equipment storage, and, emergency operation centers);

(B)

Emergency medical (hospitals, ambulance service centers, urgent care centers having emergency treatment functions, and non-ambulatory surgical structures but excluding clinics, doctors offices, and non-urgent care medical structures that do not provide these functions);

(C)

Designated emergency shelters;

(D)

Communications (main hubs for telephone, broadcasting equipment for cable systems, satellite dish systems, cellular systems, television, radio, and other emergency warning systems, but excluding towers, poles, lines, cables, and conduits);

(E)

Public utility plant facilities for generation and distribution (hubs, treatment plants, substations and pumping stations for water, power and gas, but not including towers, poles, power lines, buried pipelines, transmission lines, distribution lines, and service lines); and

(F)

Air transportation lifelines (airports (municipal and larger), helicopter pads and structures serving emergency functions, and associated infrastructure, aviation control towers, air traffic control centers, and emergency equipment aircraft hangars).

(2)

Specific exemptions to this category include wastewater treatment plants (WWTP), non-potable water treatment and distribution systems, and hydroelectric power generating plants and related appurtenances.

(3)

Public utility plant facilities may be exempted if it can be demonstrated to the satisfaction of the City Council that the facility is an element of a redundant system for which service will not be interrupted during a flood. At a minimum, it shall be demonstrated that redundant facilities are available (either owned by the same utility or available through an intergovernmental agreement or other contract) and connected, the alternative facilities are either located outside of the 100-year floodplain or are compliant with the provisions of this Article, and an operations plan is in effect that states how redundant systems will provide service to the affected area in the event of a flood. Evidence of ongoing redundancy shall be provided to the City Council on an as-needed basis upon request.

(4)

Hazardous materials facilities include facilities that produce or store highly volatile, flammable, explosive, toxic and/or water-reactive materials. These facilities may include:

(A)

Chemical and pharmaceutical plants (chemical plant, pharmaceutical manufacturing);

(B)

Laboratories containing highly volatile, flammable, explosive, toxic and/or water-reactive materials;

(C)

Refineries;

(D)

Hazardous waste storage and disposal sites; and

(E)

Above ground gasoline or propane storage or sales centers.

(5)

Facilities shall be determined to be critical facilities if they produce or store materials in excess of threshold limits. If the owner of a facility is required by the Occupational Safety and Health Administration (OSHA) to keep a material safety data sheet (MSDS) on file for any chemicals stored or used in the work place, and the chemical(s) is stored in quantities equal to or greater than the threshold planning quantity (TPQ) for that chemical, then that facility shall be considered to be a critical facility. The TPQ for these chemicals is: either 500 pounds or the TPQ listed (whichever is lower) for the 356 chemicals listed under 40 CFR § 302 (2010), also known as extremely hazardous substances (EHS); or 10,000 pounds for any other chemical. This threshold is consistent with the requirements for reportable chemicals established by the Colorado Department of Public Health and Environment. OSHA requirements for MSDS can be found in 29 CFR § 1910 (2010). The Environmental Protection Agency (EPA) regulation "Designation, Reportable Quantities, and Notification," 40 CFR § 302 (2010) and OSHA regulation "Occupational Safety and Health Standards," 29 CFR § 1910 (2010) are incorporated herein by reference and include the regulations in existence at the time of the promulgation this Ordinance, but exclude later amendments to or editions of the regulations.

(6)

Specific exemptions to this category include:

(A)

Finished consumer products within retail centers and households containing hazardous materials intended for household use, and agricultural products intended for agricultural use.

(B)

Buildings and other structures containing hazardous materials for which it can be demonstrated to the satisfaction of the local authority having jurisdiction by hazard assessment and certification by a qualified professional (as determined by the local jurisdiction having land use authority) that a release of the subject hazardous material does not pose a major threat to the public.

(C)

Pharmaceutical sales, use, storage, and distribution centers that do not manufacture pharmaceutical products.

These exemptions shall not apply to buildings or other structures that also function as critical facilities under another category outlined in this article.

(7)

At-risk population facilities include medical care, congregate care, and schools. These facilities consist of:

(A)

Elder care (nursing homes); The lowest floor (including basement), electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities (including ductwork), must be elevated to one foot above the base flood elevation that existed prior to the placement of fill, or together with attendant utility and sanitary facilities be designed so that the structure or addition is watertight to at least one foot above the base flood level that existed prior to the placement of fill with walls substantially impermeable to the passage of water and with structural components having the capability of resisting hydrostatic and hydrodynamic loads of effects of buoyancy.

(B)

Congregate care serving 12 or more individuals (day care and assisted living);

(C)

Public and private schools (pre-schools, K-12 schools, before-school and after-school care serving 12 or more children).

(8)

Facilities vital to restoring normal services including government operations. These facilities consist of:

(A)

Essential government operations (public records, courts, jails, building permitting and inspection services, community administration and management, maintenance and equipment centers);

(B)

Essential structures for public colleges and universities (dormitories, offices, and classrooms only).

These facilities may be exempted if it is demonstrated to the City Council that the facility is an element of a redundant system for which service will not be interrupted during a flood. At a minimum, it shall be demonstrated that redundant facilities are available (either owned by the same entity or available through an intergovernmental agreement or other contract), the alternative facilities are either located outside of the 100-year floodplain or are compliant with this Ordinance, and an operations plan is in effect that states how redundant facilities will provide service to the affected area in the event of a flood. Evidence of ongoing redundancy shall be provided to the City Council on an as-needed basis upon request.

(c)

Protection for Critical Facilities. All new and substantially improved critical facilities and new additions to critical facilities located within the special flood hazard area shall be regulated to a higher standard than structures not determined to be critical facilities. For the purposes of this Ordinance, protection shall include one of the following:

(1)

Location outside the special flood hazard area; or

(2)

Elevation of the lowest floor or floodproofing of the structure, together with attendant utility and sanitary facilities, to at least two feet above the base flood elevation.

(d)

Ingress and Egress for New Critical Facilities. New critical facilities shall, when practicable as determined by the City Council, have continuous non-inundated access (ingress and egress for evacuation and emergency services) during a 100-year flood event.

[Source: Ord. 1477, 2007; 1662, 2013]

Section 11-52-14. Variance and Appeal Procedure.

(a)

Designated Appeal Board. The Board of Adjustment shall hear and decide appeals and requests for variance from the requirements of this Article 52, in accordance with the provisions of Article 42 of this Zoning Ordinance with the special provisions provided below.

(b)

Evaluation Criteria, Variances and Appeals. In passing upon such application for variance or appeal, the Board of Adjustment shall consider:

(1)

All technical evaluations, all relevant factors, and standards specified in other sections of this Article 52;

(2)

The danger to life and property due to flooding or erosion damage;

(3)

The susceptibility of any proposed development, structure, facility, and property to flood damage and the effect of such damage on the individual owners of the site in question or any other sites within or outside of the boundaries of the City;

(4)

The importance to the community of the services provided by the proposed development, structure, facility, or use of the property;

(5)

The availability of alternative locations for the proposed use which are not within a special flood hazard area;

(6)

The safety of access to the site by ordinary emergency vehicles in times of flood;

(7)

The relationship of the proposed use to the floodplain management program for the area;

(8)

The expected heights, velocity, duration, rate of rise and sediment transport of the floodwaters expected at the site; and

(9)

The cost of providing governmental services during and after flood conditions, including maintenance and repair of public utilities and facilities.

(c)

Variance Limitations. A variance may be issued only in accordance with the following limitations:

(1)

For new construction and substantial improvements on lots of one-half acre or less and contiguous to and surrounded by lots in a special flood hazard area with structures with the lowest floor constructed below the base flood level and provided that the criteria established in Section 11-52-11(b) have been fully considered.

(2)

Variances shall not be granted within any floodway designated in the flood insurance study of the City of Northglenn if any increase in flood levels during the base flood discharge would result.

(3)

Variances shall only be granted upon determination that the variance is the minimum necessary to afford relief.

(4)

Variances shall only be granted upon determination that failure to grant the variance would result in exceptional hardship to the applicant.

(5)

Determination that the granting of a variance will not result in increased flood heights, additional threats to public safety, extraordinary public expense, creation of nuisances, cause fraud and/or victimization of the public, or conflict with any existing City ordinances or regulations.

(d)

Conditional Approval. Upon consideration of the criteria listed in Section 11-52-14(b), and the purposes of this Article 52, the Board of Adjustment may attach such conditions to the granting of variances, as it deems necessary.

(e)

Records of Appeals and Variances. The floodplain administrator shall maintain the records of all appeal actions, including technical information, and report any variances to the Federal Emergency Management Agency.

(f)

Recording. Notice of variances granted shall be recorded at the office of the Adams County Clerk and Recorder.

(g)

Notice of Increased Cost of Flood Insurance. Any applicant to whom a variance is granted shall be given written notice by the floodplain administrator that the cost of flood insurance will be commensurate with the increased risk.

[Source: Ord. 1662, 2013]