ORDINANCE NO.  501.00

 

                                                                          IN THE MATTER OF ZONING THE

                                                                                DETROIT LAKES AIRPORT

 

THE CITY COUNCIL OF THE CITY OF DETROIT LAKES, MINNESOTA, DOES ORDAIN:

 

Section 1.  Definitions:  As used in this ordinance, unless the context otherwise requires:

 

1.  Airport:  Means Detroit Lakes Airport.

 

2.  Airport Elevation:  Means the established elevation of the highest point on the usable landing area.

 

3.  Airport Hazard:  Means any structure, tree, or use of land which obstructs the airspace required for, or is otherwise hazardous to, the flight of aircraft in landing or taking off at the airport.

 

4.  Airport Reference Point:  Means the point established as the approximate geographic center of the airport landing area and so designated.

 

5.  Height:  For the purpose of determining the height limits in all zones set forth in this ordinance and shown on the zoning map, the datum shall be mean sea level elevation unless otherwise specified.

 

6.  Instrument Runway:  Means a runway equipped or to be equipped with a precision electronic navigation aid or landing aid or other air navigation facilities suitable to permit the landing of aircraft by an instrument approach under restricted visibility conditions.

 

7.  Landing Area:  Means the area of the Airport used for the landing, taking off, or taxiing of aircraft.

 

8.  Nonconforming Use:  Means any pre-existing structure, tree, natural growth, or use of land which is inconsistent with the provision of this ordinance or any amendment thereto.

 

9.  Non-instrument Runway:  Means a runway other than an instrument runway.

 

10. Person: Means an individual, firm, partnership, corporation, company, association, joint stock association or public body politic and includes a trustee, receiver, assignee, administrator, executor, guardian, or other representative.

 

11. Runway:  Means the paved surface of an airport landing strip.

 

12. Structure:  Means an object constructed or installed by man, including, but without limitation, buildings, towers, smoke-stacks, and overhead transmission lines.

 

13. Tree:  Means any object of natural growth.

 

Section 2.  Zones:  In order to carry out the provisions of this ordinance, there are hereby created and established certain zones which include all of the land lying within the instrument approach zones, non-instrument approach zones, transition zones, horizontal zone, and conical zone.  Such areas and zones are shown on the Detroit Lakes Airport Zoning Map consisting of two (2) pages prepared by Winston C. Larson & Associates and dated 1970, which is attached to this ordinance and made a part hereof.  The variance zones are hereby established and defined as follows:

 

1.  Instrument Approach Zone:  An instrument approach zone is established at each end of the instrument runway for instrument landings and takeoffs.  The instrument approach zones shall have a width of 1,000 feet at a distance of 200 feet beyond each end of the runway, widening thereafter uniformly to a width of 16,000 feet at a distance of 50,200 feet beyond each end of the runway, its centerline being he continuation of the centerline of the runway.

 

2.  Non-instrument Approach Zone:  A non-instrument approach zone is established at each end of all non-instrument runway for non-instrument landings and takeoffs. The non-instrument approach zone shall have a width of 500 feet at a distance of 200 feet beyond each end of the runway, widening thereafter uniformly to a width of 2,500 feet at a distance of 10,200 feet beyond each end of the runway, its centerline being the continuation of the center-line of the runway.

 

3.  Transition Zones (not applicable to VFR airports):  Transition zones are hereby established adjacent to each instrument and non-instrument runway and approach zone as indicated on the zoning map.  Transition zones symmetrically located on either side of runways have variable widths as shown on the zoning map.  Transition zones extend outward from a line 250 feet on either side of the centerline of the non-instrument runway, for the length of such runway plus 200 feet on each end; and 500 feet on either side of the centerline of the instrument runway, for the length of such plus 200 feet on each end, and are parallel and level with such runway centerlines.  The transition zones along such runways slope upward and outward one (1) foot vertically for each seven (7) feet horizontally to the point where they intersect the surface of the horizontal zone.  Further, transition zones are established adjacent to the instrument approach zones for the entire length of the approach zones, and the non-instrument approach extends upward and outward on a seven (7) to one (1) slope until it intersects the horizontal  on conical surfaces. These transition zones have variable widths, as shown on the zoning map.  Such transition zones flare symmetrically with either side of the runway approach zones from the base of such zones and slope upward and outward at the rate of one (1) foot vertically for each seven (7) feet horizontally to the points where they intersect the surfaces of the horizontal and conical zones.  Additionally, transition zones are established adjacent to the instrument approach zone where it projects through and beyond the limits of the conical zone, extending a distance of 5,000 feet measured horizontally from the edge of the instrument approach zones at right angles to the continuation of the centerline of the runway.

 

4.  Horizontal Zone:  A horizontal zone is hereby established as the area within a circle with its center at the Airport Reference Point and having a radius of 7,000 feet.  The horizontal zone does not include the instrument and non-instrument approach zones and the transition zones.

 

5.  Conical Zone: A conical zone is hereby established as the area that commences at the periphery of the horizontal zone and extends outward therefrom a distance of 5,000 feet.  The conical zone does not include the instrument approach zones and transition zones.

 

6.  Land Use Safety Zone:  In order to carry out the purpose of this ordinance, there are hereby created and established the following safety zones:

 

                        (a)       Zone A:  All that land in the approach zone of a runway which is located within a horizontal distance of 3,730 feet from each end of the primary zone.

 

                        (b)       Zone B:  All that land in the approach zones of a runway which is located within a horizontal distance of 5,600 feet from each end of the primary zone and is not included in Zone A.

 

                        (c)        All that land which is enclosed within the perimeter of the horizontal zone and which is not included in Zone A or Zone B.

 

Section 3.  Height Limitations:  Except as otherwise provided in this ordinance, no structure or tree shall be erected, altered, allowed to grow or maintained in any zone created by this ordinance to a height in excess of the height limit herein established for such zone.  Such height limitations are hereby established for each of the zones in question as follows:

 

1.  Instrument Approach Zone:  One (1) foot in height for each fifty (50) feet in horizontal distance beginning at a point 200 feet from and at the centerline elevation of the end of the instrument runway and extending until it intersects the horizontal zone then extending horizontally until it reaches the periphery of the horizontal zone, then extending upward on a fifty (50) to one (1) slope to a distance of 10,200 feet from the end of the runway; thence one (1) foot in height for each forty (40) feet in horizontal distance to a point 50,200 feet from the end of the runway.

 

2.  Non-instrument Approach Zone:  One (1) foot in height for each forty (40) feet in horizontal distance beginning at a point 200 feet from and at the centerline elevation of the end of the non-instrument runway and extending to a point where it intersects the horizontal zone and continues horizontally until it reaches the periphery of the horizontal zone, then extending upward at a forty (40) to one (1) slope to a point 10,200 feet from the end of the runway.

 

3.  Transition Zone:  One (1) foot in height for each seven (7) feet in horizontal distance beginning at a point 250 feet normal to and at the elevation of the centerline of non-instrument runways, extending 200 feet beyond each and thereof and 500 feet normal to and at the elevation of the centerline of the instrument runway, extending 200 feet beyond each end thereof, extending to a height of 100 feet above the airport elevation which is 1,396 feet above the mean sea level.  In addition to the foregoing, there are established height limits of one (1) foot vertical height for each seven (7) feet horizontal distance measured from the edge of all approach zones for the entire length of the approach zones and extending upward and outward to the points where they intersect the horizontal or conical surfaces.  Further, where the instrument approach zone projects through and beyond the conical zone, a height limit of one (1) foot for each seven (7) feet of horizontal distance shall be maintained beginning at the edge of the instrument approach zone and extending a distance of 5,000 feet from the edge of the instrument approach zone measured normal to the center-line of the runway extended.

 

4.  Horizontal Zone:  One hundred feet (100) above the airport elevation or a height of 1,396 feet above mean sea level.

 

5.  Conical Zone:  One (1) foot in height for each twenty (20) feet of horizontal distance at the periphery of the horizontal zone, extending to a height of 1,746 feet above the airport elevation.

 

Section 4.  Use Restrictions:

 

 (1) General:  Subject at all times to the height restrictions set forth in Sub Section 6, Paragraph 3, no use shall be made of any land in any of the safety zones defined with the operations of radio or electronic facilities on the Airport, or with radio or electronic communications between the Airport and aircraft, makes it difficult for pilots to distinquish between airport lights and other lights, results in glare in the eye of pilots using the airport, impairs visibility in the vicinity of the airport, or otherwise endangers the landing, taking off, or maneuvering of aircraft.

 

(2)  Zone A:  Subject at all times to the height restrictions set forth in Sub Section 6, Paragraph 3k and to the general restrictions contained in Sub Section 4, Paragraph 1.

Areas designated as Zone 1, shall contain no buildings and shall be restricted to those uses which will not create, attract, or bring together an assembly of persons thereon.  Permitted uses may include agriculture, light outdoor recreation (nonspectator), and auto parking.

 

(3)  Zone B:  Subject at all times to the height restrictions set forth in Sub Section 6, Paragraph 3, and to the general restrictions contained in Section 4, areas designated as Zone B shall be used for the following purposes only:

 

                                                (a)       For agricultural and residential purposes, pro-vided there shall not be more than one single family dwelling per three acre tract of land.

 

                                                (b)       Any commercial or industrial use which meets the following minimum standards:

 

1.  Each single commercial or industrial use shall not create, attract, or bring together a site population that would exceed 15 times that of the site acreage.

 

2.  Each single commercial or industrial site shall be of a size not less than three acres.

 

3.  Each single commercial or industrial site shall contain no dwellings and shall contain no more than one building per three acre tract of land.

 

4.  The maximum ground area to be covered by a single commercial or industrial building shall not exceed the following minimum ratios with respect to the building site area:

 

                                                                                                                  1st Floor        Max Site

At Least      But Less                                                      Bldg. Area      Population

(Acres)     Than (Acres)                     Ratio                   (Sq. Ft.)     (15 Persons-A)

 

                        3                      4                                 12.1                          10,900           45

                                                                                    12.1

                        4                       6                                 10.1                         17,400           60

                                                                                    10.1

6                      10                                8.1                           32,600           90

                                                                                     8.1

                        10                                                        6.1                           72,500         150

                        20                                                        4.1                         218,000         300

                                                and up                         4.1

 

                        (c)        The following uses are specifically prohibited in Zone B:  churches, hospitals, schools, theatres, stadiums, hotels and motels, trailer courts, campgrounds, and other places of public or semi-public assembly.

 

4.  Zone C:  Shall contain no lights which would make it difficult for pilots to distinguish between airport lights and other lights, or results in glare in the eyes of pilots using the airport, impairs visibility in the vicinity of the airport, or otherwise endangers the landing, taking off, or maneuvering of aircraft, or any concentration of smoke that impairs the visibility in the vicinity of the airport.

 

Section 5.  Nonconforming Uses: 

 

(a)  Regulations not Retro-active.  The regulations prescribed by this ordinance shall not be construed to require the removal, lowering, or other changes or alteration of any structure or tree not conforming to the regulations as of the effective date of this ordinance, or otherwise interfere with the continuance of any nonconforming use.  Nothing herein contained shall require any change in the construction, alteration, or intended use of any structure, the construction or alteration of which was begun prior to the effective date of this ordinance and is diligently prosecuted.

 

(b)  Marketing and Lighting.  Notwithstanding the preceding provision of this Section, the owner of any nonconforming structure or tree is hereby required to permit the installation, operation, and maintenance thereon of such markers and lights as shall be deemed necessary by the Airport Commission to indicate to the operators of aircraft in the vicinity of the airport, the presence of such airport hazards.  Such markers and lights shall be installed, operated, and maintained at the expense of the Airport Commission.

 

Section 6.  Permits:

 

 (a)  Future Uses:  Except as specifically provided in Paragraphs 1, 2, and 3 hereunder, no material change shall be made in the use of the land and no structure or tree shall be erected, altered, planted, or otherwise established in any zone hereby created unless a permit therefor shall have been applied for and granted.  Each application for a permit shall indicate the purpose for which the permit is desired, with sufficient particularity to permit it to be determined whether the resulting use, structure, or tree would conform to the regulations herein prescribed.  If such determination is in the affirmative, the permit shall be granted:

 

1.  In the area lying within the limits of the horizontal zone and conical zone, no permit shall be required for any tree or structure less than 75 feet of vertical height above the ground, except when because of terrain, land contour or topographic features, such tree or structure would extend above the height limits prescribed for such zone.

 

2.  In the areas lying within the limits of the instrument and non-instrument approach zones but at a horizontal distance of not less than 4,200 feet from each end of the runways, no permit shall be required for any tree or structure less than 75 feet of vertical height above the ground, except when such tree or structure would extend above the height limit prescribed for such instrument or non-instrument approach zone.

 

3.  In the areas lying within the limits of the transition zones beyond the perimeter of the horizontal zone, no permit shall be required for any tree or structure less than 75 feet of vertical height above the ground except when such tree or structure, because of terrain, land contour, or topographic features would extend above the height limit prescribed for such transition zones.

 

Nothing contained in any of the foregoing exceptions shall be construed as permitting or intending to permit any construction, alteration, or growth of any structure or tree in excess of any of the height limits established by this ordinance except as set forth in Section 3.

 

(b)  Existing Uses.  No permit shall be granted that would allow the establishment or creation of an airport hazard or permit a nonconforming use, structure, or tree to be made or become higher, or become a greater hazard to air navigation; than it was on the effective date of this ordinance or any amendments thereto or than it is when the application for a permit is made.  Except as indicated, all applications for such a permit shall be granted.

 

(c)  Nonconforming Uses Abandoned or Destroyed.  Whenever the zoning administrator determines that a nonconforming structure or tree has been abandoned or more than eighty (80) percent torn down, physically deteriorated, or decayed, no permit shall be granted that would allow such structure or tree to exceed the applicable height limit or otherwise deviate from the zoning regulations.

  

(d)  Variances.  Any person desiring to erect or increase the height of any structure, or permit the growth of any tree, or use his property, not in accordance with the regulations prescribed in this ordinance, may apply to the Board of Adjustment for a variance from such regulations.  Such variances shall be allowed where it is duly found that a literal application or enforcement of the regulations would result in practical difficulty or unnecessary hardship and the relief granted would not be contrary to the public interest but will do substantial justice and be in accordance with the spirit of this ordinance.

 

(e)  Hazard Marking and Lighting.  Any permit or variance granted may, if such action is deemed advisable to effectuate the purpose of this ordinance and be reasonable in the circumstances, be conditioned as to require the owner of the structure or tree in question to permit the Airport Commission at its own expense to install, operate, and maintain thereon such markers and lights as be necessary to indicate to flyers the presence of any airport hazard.