Search Municipal Code

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.

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.

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:

Protect human life and health;

Minimize expenditure of public money for costly flood control projects;

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

Minimize business interruptions;

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

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;

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

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

[Source: Ord. 1477, 2007]

Section 11-52-4. Definitions.

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

Area of Special Flood Hazard means the land within the City subject to a one percent or greater chance of flooding in any given year. Areas of special flood hazard are more specifically the area designated as zones A, AO, AH, AL-30, AE, A99, AR, AR/AL-30, AR/AE, AR/AO, AR/AH, AR/A, VO, or VL-30, VE, or V on the flood insurance rate map. for purposes of these regulations, the term "Special Flood Hazard Area" is synonymous with the term "Area of Special Flood Hazard".

Base Flood is synonymous with the 100-year flood and intermediate regional flood, and means the flood having a one percent chance of being equaled or exceeded in any given year.

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.

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

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

The overflow of streams, rivers, or other inland water, or

The unusual and rapid accumulation of surface waters or runoff of surface waters from any source.

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.

Flood Insurance Study means the official report, originally dated March 1978 and prepared for the City of Northglenn, 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.

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.

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.

Floodway is the channel of a river or other watercourse and the adjacent land areas, as designated on the Floodway Map, that must be reserved in order to discharge the 100-year flood without cumulatively increasing the water surface elevation more than one foot.

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

Hundred Year Flood is synonymous with Base Flood.

Lowest Floor means the lowest floor of the lowest enclosed area (including basement). An unfinished or flood resistant enclosure, usable solely for parking of 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 this Ordinance.

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".

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.

Mean Sea Level means the national geodetic vertical datum (NGVD) of 1929 or other datum, to which base flood elevations are referenced.

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

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.

Recreational Vehicle means a vehicle which is:

Built on a single chassis;

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

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

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

Start of construction includes substantial improvement, and means the date the building permit was issued provided the actual start of construction, repair, reconstruction, rehabilitation, placement of addition, or other improvement was within 180 days of the permit date. The actual start means 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, temporary forms; nor does it include the installation on the property of accessory buildings, such as garages or sheds not occupied as dwelling units or not part of the main structure.

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

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:

Before the improvement or repair is started; or

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

For the purposes of this definition, substantial improvement is considered to occur when the first alteration of any wall, ceiling, floor, or other structural part of the building commences, whether or not that alteration affects the external dimensions of the structure. The term does not, however, include any project for improvement of a structure to comply with existing State or local health, sanitary, or safety code specifications which are solely necessary to assure safe living conditions. 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.

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.

[Source: Ord. 1477, 2007]

Section 11-52-5. General Provisions.

Jurisdiction. This Article 52 shall apply to all areas of special flood hazard.

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 the City of Northglenn originally dated March 1978, and this study and accompanying Flood Insurance Rate Maps, and any revisions thereto, 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 Community Development.

Interpretation. The provisions of this Article 52 shall be held to be minimum requirements and shall not be deemed a limitation or repeal of any other powers granted by State Statutes.

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.

Compliance. No structure or land shall hereafter be constructed, located, extended, converted, or altered without full compliance with the terms of this Article 52.

Abrogation and Greater Restrictions. This Article 52 is not intended to repeal, abrogate, or impair any existing easement, covenants, or deed restrictions. However, where this Article 52 and other ordinance, easement, covenant, or deed restriction, conflict, or overlap, whichever imposes the more stringent restrictions shall prevail.

[Source: Ord. 1477, 2007]

Section 11-52-6. Administration.

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

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

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

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;

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.

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.

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.

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

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.

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

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

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

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.

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

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.

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.

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 flood plain 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:

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

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

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

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.

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

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

Mapping Disputes. The flood plain 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]

Section 11-52-7. New Subdivisions.

The design of all new land subdivisions (not including resubdivisions) in special flood hazard areas shall be consistent with the need to minimize flooding.

All new subdivisions shall have public utilities and facilities located and constructed to minimize flood damage.

All new subdivisions shall have adequate drainage provided to reduce exposure to flood damage.

Base flood elevation data shall be provided.

[Source: Ord. 1477, 2007]

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

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

Anchoring.

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.

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.

Any additions to the manufactured home shall be similarly anchored.

Construction Materials and Methods.

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

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.

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.

Utilities.

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

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.

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

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.

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.

Residential Construction. New construction and substantial improvement of any residential structure shall have the lowest floor (including basement) elevated to or above the base flood elevation.

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:

Be floodproofed so that below the base flood elevation the structure is watertight with walls substantially impermeable to the passage of water;

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

Manufactured Homes. All manufactured homes erected, installed, or substantially improved shall be anchored in accordance with Section 11-52-8(b) and shall be attached to a permanent foundation. The lowest floor shall be elevated to or above the base flood elevation.

[Source: Ord. 1477, 2007]

Section 11-52-10. Floodway Restrictions.

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.

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.

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.

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

Be on the site for fewer than 180 consecutive days,

Be fully licensed and ready for highway use, or

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.

[Source: Ord. 1477, 2007]

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

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.

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

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

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

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;

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

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

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

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

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

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

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

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.

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.

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

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

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.

Conditional Approval. Upon consideration of the criteria listed in Section 11-52-11(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.

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

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

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

[Source: Ord. 1477, 2007]

Section 11-52-12. Severability. If any provision of this Ordinance or the application thereof to any person, property, or circumstance shall be judged invalid by any court, such invalidity shall not affect or impair the integrity or validity of the remaining portions of this Ordinance or the application thereof to other persons, property, or circumstances.

[Source: Ord. 1477, 2007]

Section 11-52-13. Reserved.

[Source: Ord. 1477, 2007]