AN ORDINANCE AMENDING
SECTION 10.89
OF THE MANKATO CITY CODE
WHEREAS, zoning ordinances are
designed for the purpose of promoting the public health, safety, and general welfare; and
WHEREAS, from time to time it is
in the best interest of the community to amend the zoning ordinance for the purpose of
promoting the public health, safety, and general welfare; and
WHEREAS, the City Council
established a Task Force to draft an exterior lighting ordinance to be included in Chapter
10 (Zoning) of the Mankato City Code; and
WHEREAS, the Task Force drafted
a proposed ordinance; and
WHEREAS, the Environmental
Committee has reviewed the proposed ordinance and has recommended adoption by the City
Council; and
WHEREAS, the Planning Commission
has reviewed the proposed ordinance and has recommended adoption by the City Council.
NOW, THEREFORE, BE IT ORDAINED
by the Mankato City Council that the following shall be adopted as Section 10.89,
Subdivision 4, of the Mankato City Code:
Section 10.89, Subdivision 4.
Exterior Lighting
Subpart 1. Purpose and Intent. The
purpose of this lighting ordinance is to create standards for outdoor lighting which will
provide for nighttime safety, security and utility while reducing light pollution, light
trespass, and conserving energy.
It is the intent of this ordinance
to require appropriate lighting levels, efficient (watts to lumens) lighting sources, full
cut off lighting, and to minimize/discourage lighting glare, lighting pollution and
lighting trespass.
Subpart 2. Definitions: For the purpose of applying the regulations of this section,
the following definitions shall apply:
1)Cutoff: The point at which all
light rays emitted by a lamp, light source or luminaire is completely eliminated (cutoff)
at a specific angle above the ground.
2)Cutoff Angle: The maximum angle
formed by a line drawn in the direction of emitted light rays at the light source and a
line perpendicular to the ground from the light source.
3)Full Cutoff-Type Luminaire: A
luminaire constructed or shielded to direct all light at a cutoff angel of less than 90
degrees. Also, referred to as a Horizon Limited Luminaire.
4)Foot-candle: A unit of
illumination produced on a surface, all points of which are one foot from a uniform point
source of one-candle.
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Exterior Lighting
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5)Glare: Direct light emitted from a
light source which causes eye discomfort.
- 6)Light Pollution: The shining of light produced by a
luminaire above the height of the luminaire and into the sky.
7)Light Trespass: The shining of light produced by a luminaire beyond the boundaries of
the property on which it is located.
8)Luminaire: A complete lighting
unit consisting of a light source and all necessary mechanical, electrical and decorative
parts.
- 9)Lighting Districts: The districts as depicted on
the Official District Lighting Map. The Official Lighting District Map (attached) shall be
considered part of this ordinance.
Subpart 3. General Standards: In addition to the regulations specific to each
lighting district outlined in Subpart 7 of this Subdivision, the following provisions
shall apply:
A. General Standards for Lighting on
Private Property:
1) No flashing light shall be
permitted.
2)Light for outdoor advertising
shall be designed to function as full cut off luminaires. Lighting intended for outdoor
advertising which projects light into the sky shall be prohibited. The temporary use of
lasers and spotlights that project light into the sky may be allowed subject to the
restrictions of temporary signs contained in Section 10.87.
3)Light sources or luminaires shall
not be located within transitional yards except along pedestrian walkways.
4) All luminaires located on
commercial, industrial, or institutional property shall be designed so that the light
source (bulb or lamp) is completely shielded from direct view of an observer standing at a
point five feet above grade on the lot line abutting a transitional yard or at any
location on residentially zoned property
5)All luminaires located on private
property shall be designed or positioned so that the maximum illumination at the property
line shall not exceed one-half (&127;) foot candle.
6)The use of exterior lighting for
nonresidential uses shall observe the same hours of operation as the use itself, except
that a minimum level of lighting for security purposes may be left on beyond the normal
hours of operation.
7)Lighting for canopies covering
fueling stations at automobile service stations and drive-thru facilities shall not
illuminate abutting properties and the luminaires shall be designed so that the light
source (bulb or lamp) is completely shielded from direct view of an observer standing at
the property line at a point five feet above grade.
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Exterior Lighting
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8)Because of their unique
requirement for nighttime visibility and their limited hours of operation, ball diamonds,
playing fields and tennis courts are exempted from the general standards of this section.
Lighting for these outdoor recreational uses shall be shielded to minimize light and glare
from spilling over onto adjacent residential properties. The maximum permitted
illumination at the property line shall not exceed two foot candles.
9)As part of the approval of public
street or sidewalk projects, the City Council may vary from the requirements of this
Section.
10)The illumination levels contained
in the Lighting Handbook, Illuminating Engineering Society of North America, as amended
from time to time, shall be used as a guide for providing adequate and safe illumination
levels. The City Council may require conformance with the illumination levels contained in
the Lighting Handbook, Illuminating Engineering Society of North America as part of the
review and approval of a private or public development project.
B.Method of Measurement:
Illumination levels shall be measured in foot candles with a meter sensor in a horizontal
position at an approximate height of 3 feet above grade. Maximum illumination readings are
to be taken directly beneath the luminaire. Readings should normally be taken after a
cumulative initial lamp burn in period of at least 200 hours.
To determine minimum permitted
illumination, illumination levels shall be measured in foot candles with a meter sensor in
a horizontal position at an approximate height of 3 feet above grade. The point at which
readings shall be taken is dependent upon the area classification and fixture arrangement
as follows:
1.Opposite Spaced Street Lighting:
(Requires 2 readings) Readings should be taken as described above 1.) At the center of the
street, equidistant between two sets of fixtures, and 2.) at the curbline equidistant
between two fixtures on the same side of the street.
2.Public Sidewalks: (Sharing a
lighting system with the street) Readings should be taken as described above at the
farthest "house" side of the pavement, equidistant between two fixtures.
3.Public Sidewalks: (Separate
lighting system from street lighting) Readings should be taken as described above in the
center of the pavement, equidistant between two fixtures.
4.Parking Areas: (Perimeter lit)
Readings should be taken as described above equidistant between two fixtures at the
perimeter, as well as at the location of the property farthest from the fixtures.
5.Parking Areas: (Centrally lit or
combination of central/perimeter lighting) Readings should be taken as described above in
the center of large parking areas, equidistant between all of the fixtures illuminating
the area. If perimeter lighting is also used, take readings as described in Parking Areas,
Perimeter lit.
In instances where only one fixture
is located on a property, the minimum illumination level shall be measured in foot candles
with a meter sensor in a horizontal position located approximately 3 feet above grade.
Readings should be taken at the location on the property farthest from the fixture.
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Exterior Lighting
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Subpart 4. Exemptions. The
following are exempt from the standards contained in this ordinance:
1)Decorative seasonal lighting with
a power rating of less than or equal to 75 watts.
2)Lighting for one- and two family
dwellings, provided that the lamps have a power rating of less than or equal to 75 watts,
a cut off component is incorporated in the design of the luminaire, and the lighting level
at the property line shall not exceed the maximum level contained in Subpart 3. The
maximum lighting level at the property line may be exceeded in cases where the lamp is
turned on and off by a motion sensor and the lamp is not on for a continuous period
exceeding ten minutes.
3)Temporary emergency lighting used
by police, fire fighters, or other emergency services, as well as all vehicular
luminaires.
4)Hazard warning luminaires which
are required by federal regulatory agencies.
Subpart 5. Exterior Lighting Plan Required.
A lighting plan shall be required
anytime exterior lighting is proposed, or modified, that is associated with use of greater
intensity than a one or two-family dwelling. The lighting plan shall be submitted with the
site plan information required in Section 10.90, Subd. 6, of the Mankato City Code.
The plan shall be prepared by a
certified engineer, architect, landscape architect or lighting engineer or designer. The
plan shall identify the location, size, type of luminaire, height of luminaire, a
photometric plan of the site, and fixture data sheets. The plan shall also contain a
certification by the property owner or agent and the preparer of the plan that the
exterior lighting depicted on the plan complies with the requirements of this subdivision.
Once the plan is approved, the exterior lighting of the property shall conform to the
plan.
Subpart 6. Nonconforming Luminaires.
Exterior lighting luminaires in
existence on the effective date of this chapter shall be exempt from the standards of this
chapter and shall be considered legally nonconforming. Such fixtures may be repaired and
maintained. However, if any legal nonconforming luminaire is moved or damaged by any means
to an extent that its total replacement is necessary, the luminaire, or replacement, shall
comply with this subdivision.
Exterior lighting luminaires
existing on the effective date of this ordinance which are located on private commercially
zoned property and are found to direct light or glare to private property located in a
residential zoning district may be declared a public nuisance if the level of illumination
on private property located in the residential zoning district, which is caused by the
luminaire, is equal to or greater than &127; foot candle. Such fixtures shall be altered
to reduce the level of illumination in the residential zoning district to less than &127;
foot candle within six months of receiving a written notice of violation from the Zoning
Administrator.
Subpart 7. District Standards:
The zones referred to in the standards are depicted on the Official Lighting Map, as
adopted as part of this Subdivision:
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Exterior Lighting
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A. Downtown Lighting District.
Luminaires located in the Downtown Lighting District shall have a design that allows not
more 10 percent of the light from the luminaire to be projected above the fixture.
Luminaires shall be designed to provide adequate pedestrian illumination levels as
outlined in Lighting Handbook, Illuminating Engineering Society of North America. The
appearance of luminaires shall be complementary and compatible with significant
architectural features or themes found in the Downtown Lighting District.
B. General Lighting District.
Luminaires located in the General Lighting District (GLD) shall be designed to function as
full cutoff luminaires and prevent light from the luminaire to be projected into the sky
or across zoning lot lines.
Exceptions to the full cut off
requirement of this district may be approved by the City Council as part of the review and
approval of an Institutional Overlay District, planned unit development, or street
improvement. Standards for considering an exception include all of the following:
a.The proposed development or
district is characterized by a high degree of pedestrian traffic.
b.The purpose and design of the
luminaire are to provide adequate pedestrian illumination levels as outlined in Lighting
Handbook, Illuminating Engineering Society of North America.
c.The purpose of the luminaire's
design is to be compatible with significant architectural features or themes associated
with the development or planning area.
d.No full cut off luminaire is
available which is architecturally compatible with the development and provides adequate
illumination levels for pedestrian traffic.
e.The design of the fixture
incorporates a cut off component which allows a minimal amount of light emitted from the
luminaire to be projected above the height of the luminaire.
f.The luminaire shall comply with all other requirements of this Section.
This Ordinance shall, in accordance
with the provisions of Sections 2.14 and 5.06 of the Mankato City Charter, become
effective thirty (30) days after publication of notice of its adoption.
Adopted this ________ day of ___________________________, 1997.
_______________________________________
Mayor
Attest: _________________________________
City Clerk