The following overlay districts shall be deemed to be overlays
upon the various underlying base zoning districts. These overlay districts
are enacted to regulate land uses, building and structure forms, and
other standards throughout Robinson Township. All requirements set
forth by the overlay districts as set forth by this article shall
supersede the requirements of the underlying base zoning districts
unless otherwise noted by this chapter. The type and function of overlay
districts are as follows:
A.
Mobility Overlay Districts.
(1)
The Mobility Overlay Districts create pedestrian-oriented nodes that
are centered around prominent destinations within Robinson Township,
expand the overall sidewalk, trail and multimodal circulation network
within areas of Robinson Township that can support this infrastructure,
and allow for a wider variety of land uses and building forms than
are permitted in the applicable base zoning districts.
B.
Airport Hazard Overlay District.
(1)
The Airport Hazard Overlay District addresses safety issues around
the Pittsburgh International Airport. This overlay establishes boundaries
that regulate and restrict the location and height of constructed
structures and objects of natural growth within the overlay district.
C.
Parkway Protection Overlay District.
(1)
The Parkway Protection Overlay District promotes economic development
within the overlay's define boundaries, public health, safety
and welfare of Township residents, and encourages high-quality development
and orderly community growth while protecting and preserving natural
resources and the environment.
In the event of conflicts between the provisions of this article
and any other ordinance or regulation, the more restrictive provisions
shall apply.
A.
Mobility Overlay District A - The Mall at Robinson Area (MOD - A).
(1)
Purpose. This mobility overlay district creates a pedestrian-oriented
node within Robinson Township that connects the Mall at Robinson,
existing and future residential developments, the Montour Trail, and
adjacent mobility overlay districts.
(3)
Authorized uses.
(a)
Permitted uses.
[1]
Multiple-family garden apartment dwellings.
[2]
Multiple-family low-rise apartment dwellings.
[3]
Patio homes.
[5]
Quadraplex dwellings.
[6]
Single-family detached dwellings.
[7]
Stacked attached single-family dwellings.
[8]
Townhouse dwellings.
[9]
Two-family dwelling, new.
[10]
Two-family dwelling, existing.
[11]
Day-care center, child.
[12]
Day-care center, adult.
[13]
Forestry.
[14]
Home-based business, low-impact.
[15]
Home-based business, no-impact.
[16]
Hotel/motel.
[17]
Offices, business and professional.
[18]
Offices, medical.
[19]
Planned commercial center.
[20]
Public and essential services.
[21]
Research and development facility, hazardous substances.
[22]
Retail business, convenience retail.
[23]
Retail business, shoppers retail.
(b)
Conditional uses. The following uses are permitted in accordance with the standards of this article, other applicable provisions, and Article X of this chapter:
[1]
Live-work unit.
[2]
Brew-pub.
[3]
Car wash.
[4]
Commercial recreation.
[5]
Commercial school.
[6]
Conference or training center.
[7]
Automobile sales and service.
[8]
Nursing or convalescent home.
[9]
Research and development facility, hazardous substances.
[10]
Restaurant, conventional.
[11]
Restaurant, fast-food.
[12]
School.
[13]
Smoke shop/tobacco store.
[14]
Tavern/bar.
[15]
Unified commercial development.
(4)
Area and bulk requirements.
(a)
Minimum lot area.
[1]
Single-family detached dwelling: 5,000 square feet.
[2]
Quadraplex dwelling, Stacked attached single-family dwelling:
4,800 square feet of lot area per dwelling unit.
[3]
Live-work unit: 3,000 square feet.
[4]
Other permitted residential uses: Refer to § 300-38C. Area and bulk requirements of the R-3 Minimum-Density Residential District.
[5]
Other uses: 10,000 square feet.
(8)
Sidewalks. Sidewalks shall be installed as regulated by § 250-41 of the Township of Robinson Subdivision and Land Development Ordinance, as amended. All sidewalks shall be designed in accordance with the standards as set forth by § 245-25 and § 245-26 of the Streets and Sidewalks Ordinance, as amended.
B.
Mobility Overlay District B — Clever Park Neighborhood (MOD
- B).
(1)
Purpose. This mobility overlay district creates a pedestrian-oriented
node within Robinson Township that connects public recreational facilities,
the Montour High School, existing and future residential developments,
and adjacent mobility overlay districts.
(3)
Authorized uses.
(a)
Permitted uses.
[2]
Single-family detached dwelling.
[3]
Single-family detached dwelling, existing.
[4]
Townhouse dwellings.
[5]
Two-family dwelling, new.
[6]
Two-family dwelling, existing.
[7]
Stacked attached single-family dwelling.
[8]
Farm.
[9]
Forestry.
[10]
Home-based business, no-impact.
[11]
Public and essential services.
(b)
Conditional uses. The following uses are permitted in accordance with the standards of this article, other applicable provisions, and Article X of this chapter:
(8)
Sidewalks. Sidewalks shall be installed as regulated by § 250-41 of the Township of Robinson Subdivision and Land Development Ordinance, as amended. All sidewalks shall be designed in accordance with the standards as set forth by § 245-25 and § 245-26 of the Streets and Sidewalks Ordinance, as amended.
C.
Mobility Overlay District C - Burkett Park Neighborhood (MOD - C).
(1)
Purpose. This mobility overlay district provides a walkable node
within Robinson Township, fostering pedestrian connections between
schools, shopping centers, recreational facilities, and nearby homes.
This overlay district connects to all others, promoting a cohesive
pedestrian network across all mobility overlay districts.
(3)
Authorized uses.
(a)
(b)
Conditional uses. The following uses are permitted in accordance with the standards of this article, other applicable provisions, and Article X of this chapter:
[2]
Hotel/motel.
[3]
Farming equipment sales and services.
[4]
Nursing or convalescent home.
[5]
Office, businesses and professional.
[6]
Retail business, shoppers retail.
[7]
Unified commercial development.
[8]
School.
[9]
Smoke shop/tobacco store.
[10]
Tavern/bar.
[11]
Brew-pub.
[12]
Micro-brewery.
[13]
Ale house/winery/meadery.
(4)
Area and bulk requirements.
(b)
Minimum lot width.
[1]
Single-family detached dwelling: 80 feet.
[2]
All other residential uses: 150 feet.
[3]
Unified commercial development: See § 300-98A(43).
[4]
Other uses: 55 feet.
(c)
Maximum height of structures.
[1]
Unified commercial development: See § 300-98A(43).
[2]
All other principal uses: 35 feet and 2.5 stories.
[3]
Accessory structures: 20 feet.
(d)
(8)
Sidewalks. Sidewalks shall be installed as regulated by § 250-41 of the Township of Robinson Subdivision and Land Development Ordinance, as amended. All sidewalks shall be designed in accordance with the standards as set forth by § 245-25 and § 245-26 of the Streets and Sidewalks Ordinance, as amended.
D.
Mobility Overlay District D - Settler's Cabin County Park Area
(MOD - D).
(1)
Purpose. This mobility overlay district preserves and protects one
of the most prominent public parks in the County while promoting Robinson
Township's pedestrian network and forming connections from nearby
residential and commercial areas to the Settler's Cabin County
Park.
(3)
Authorized uses.
(b)
Conditional uses. The following uses are permitted in accordance with the standards of this article, other applicable provisions, and Article X of this chapter:
(8)
Sidewalks. Sidewalks shall be installed as regulated by § 250-41 of the Township of Robinson Subdivision and Land Development Ordinance, as amended. All sidewalks shall be designed in accordance with the standards as set forth by § 245-25 and § 245-26 of the Streets and Sidewalks Ordinance, as amended.
E.
Parkway Protection Overlay District.
(1)
Purposes. The purpose of the Parkway Protection Overlay District
is to promote economic development, public health, safety and the
overall welfare of the residents of Robinson Township, to encourage
high-quality development and orderly community growth. This Overlay
District is also established to protect and preserve natural resources
and the environment and to conserve and stabilize property values.
(3)
Compliance. No structure shall be located, erected, constructed,
reconstructed, moved, altered, converted or enlarged; nor shall any
structure or land be used or be designed to be used except in full
compliance with all the provisions of this article and after the lawful
issuance of all permits and certificates required by this article.
(4)
Signs. For all regulations and requirements for signs located within the Parkway Protection Overlay District, refer to § 300-92 of this chapter.
(5)
Setbacks.
(a)
Buildings. All buildings shall be set back a minimum of two
times the maximum height of the building but in no case less than
100 feet from the nearest parkway right-of-way line, except where
the maximum depth of the lot upon which the building is located is
less than 200 feet, in which case the setback may be reduced to a
minimum of 50% of the maximum depth of the lot. However, in no case
shall the setback be reduced to less than 25 feet.
(b)
Accessory uses/parking lots/signs. All accessory uses, parking
lots and signs shall be set back at least 100 feet from the nearest
parkway right-of-way line of the parkway, except where the maximum
depth of the lot upon which the building is located is less than 200
feet, in which case the setback may be reduced to a minimum of 50%
of the maximum depth of the lot. However, in no case shall the setback
be reduced to less than 25 feet.
(c)
Retaining walls. Retaining walls shall be set back a minimum
of 35 feet from the nearest parkway right-of-way line.
(6)
Landscaped buffers.
(a)
Landscaping. All setbacks and bufferyards required by this article shall be landscaped as set forth in § 300-72 of this chapter. The exact placement of required plants shall be the decision of each user, except that the following requirements shall be satisfied:
[1]
Planting schemes shall be based on a four-season plan and materials
selected that highlight each season: spring, flowering plants; summer,
shade; fall, leaf color; winter, branch form and texture.
[2]
All buffered areas shall be seeded with grass unless ground
cover is to be established and maintained.
(b)
Views of buildings. To permit views of buildings on lots adjacent
to the parkway, up to 20% of the landscaped buffer may be planted
in low vegetation. Such planting of low vegetation shall be done in
a continuous, contiguous fashion, not interspersed throughout the
bufferyard.
(c)
Maintenance. Bufferyards shall be maintained by the owner of
the property. Debris and litter shall be cleaned on a semiannual basis.
Damage to 15% or more of the plant material for any reason, including
disease, wind or fire, shall require replacement of all such damaged
plant materials.
(d)
Ownership. Bufferyards may remain in the ownership of the original
developer of a land use or they may be transferred to any consenting
grantees, such as adjoining landowners, a park or forest preserve
district, a municipality or an open-space conservation group, provided
that Robinson Township Commissioners determine any such conveyance
adequately guarantees the protection of the bufferyards for the purposes
of this article.
(e)
Existing trees and vegetation. All existing trees and vegetation within buffers shall be protected in accordance with provisions set forth in § 300-52E(10). Existing vegetation and trees may be used to meet bufferyard landscaping requirements to the extent they satisfy all other provisions of this article.
(7)
Parking lot screening/interior landscaping. All parking lots constructed
or expanded by 5% in area or in number of spaces after the effective
date of this article shall be screened around their entire perimeter
(except on the sides directly adjacent to the buildings they serve)
with a landscaped buffer meeting the following requirements as depicted
in the accompanying illustration, which is included as an attachment
to this chapter.
(a)
Perimeter landscaping. The minimum width of any landscaped parking
lot buffer shall be 10 feet. The bufferyard shall include either of
the following:
(b)
Interior landscaping. Parking lots with more than one parking
aisle shall have a landscaped strip of a minimum width of six feet
separating each aisle. This landscaped area shall contain a minimum
of four canopy trees and three understory trees or evergreen trees
for every 100 linear feet. Parking lots with no internal aisles and
more than 10 parking bays shall have a minimum of at least one bay
of landscaping of a minimum dimension of 10 feet by 20 feet, containing
at least one canopy tree for every 10 parking spaces or fraction thereof.
(See illustration, which is included as an attachment to this chapter.)
(8)
Steep slopes provisions.
(a)
On land within the Parkway Protection Overlay District, the
following standards shall apply to all grading and development of
steep slopes, as defined below:
[1]
Twelve percent to less than 15% slope. No more than 70% of such
areas shall be developed and/or regraded or stripped of vegetation.
[2]
Fifteen percent to less than 25% slope. No more than 40% of
such areas shall be developed and/or regraded or stripped of vegetation.
[3]
Twenty-five percent to less than 30% slope. No more than 15%
of such areas shall be developed and/or regraded or stripped of vegetation.
[4]
More than 30% slope. No development shall be allowed except
upon submission of a report by a certified soil or geotechnical engineer
indicating that the steep slope may be safely developed. If development
is allowed to proceed under this subsection, no more than 15% of such
areas shall be developed and/or regraded or stripped of vegetation.
[5]
All applicants shall utilize the Soil Survey of Allegheny County
to identify landslide-prone areas on the development site. If any
landslide-prone areas are indicated, then the applicant shall have
further studies conducted by a qualified professional soils or geotechnical
engineer to determine the exact dimensions and location of the landslide-prone
areas. No such landslide-prone area may be disturbed or developed.
[6]
In any area that is cut and filled or regraded, the resulting
slope shall not exceed 33%:3:1.
[7]
All applications for subdivision or development on slopes in excess of 12% shall be accompanied by a report by a qualified professional, such as a landscape architect, planner or engineer, indicating the contours (at two-foot intervals) and percent of slope calculated at intervals of no more than 10 feet and categorized as set forth in Subsection E(8)(a)[1] through [4] throughout the property and the locations, character and extent of all areas subject to landsliding. Subdivision plats and certified site survey maps should designate landslide-prone areas as determined by the geotechnical report.
[8]
No development shall take place within 20 feet of any area determined
to be landslide-prone by a geotechnical study performed pursuant to
this article.
[9]
Where streets and roads, both public and private, are proposed
to be constructed on grades greater than 10%, evidence must be presented
that such roads can be built without environmental damage and within
acceptable public safety risks. If constructed, such streets and roads
shall, to the maximum extent feasible, respond to natural land forms
and preserve the natural character of the land. Cutting and filling
shall be held to a minimum.
(b)
Graded and filled slopes. In addition to standards set forth
in the above subsection, the following requirements shall apply to
all steep slopes within the Parkway Protection Overlay District.
[1]
Cut or filled slopes shall be limited to 33% or less. Finished
grades of 25% or less are greatly encouraged whenever possible.
[3]
To the maximum extent possible, graded slopes shall be varied
to resemble natural land contours.
[4]
Slopes exposed or revegetated in order to mitigate adverse environmental
and visual effects. Fill soil on slopes in the Parkway Protection
Overlay District must support plant growth. At a minimum, any slope
exposed or created in new development shall be landscaped or revegetated
with trees and other plant material at a density and in a pattern
as generally depicted in the accompanying illustration at the end
of this article.[6] Minimum planting per 100 horizontal feet of slope shall
include:
[6]
Editor's Note: Said illustration is included as an attachment
to this chapter.
[5]
Retaining walls or gabions may be permitted to support steep
slopes but shall not exceed five feet in height.
(9)
Stream corridors and drainage ways. All development along major stream
corridors within the Parkway Overlay District shall comply with the
following standards:
(a)
All buildings, accessory structures and parking lots shall be
set back at least 100 feet from the closest bank of designated streams.
Where application of this setback would render the site undevelopable,
up to 50% of the stream may be bridged or developed in compliance
with other local, state and federal laws, provided that the natural
channel is maintained to the maximum extent feasible.
(b)
All existing vegetation within the one-hundred-foot setback
area shall be preserved and, where necessary to provide adequate screening,
supplemented with additional landscaping.
(c)
For the purposes of this article, a major stream shall be defined
as a perennial stream as identified on relevant U.S. Geologic Survey
topographical maps.
(10)
Tree and vegetation protection survey. All plans for subdivision
or development approval shall be accompanied by an accurate delineation
of all woodland masses on the property and should identify the locations
of all trees greater than 12 inches in diameter at breast height,
their species, diameter and canopy or driplines.
(11)
Mature woodland. No more than 40% of the portion of any mature
woodland (as defined below) within the Parkway Protection Overlay
District may be cleared or developed. The remaining 60% shall be maintained
as permanent open space. Areas preferred for tree removal include
building pads, parking lots, utility trenches, detention ponds and
roads.
(12)
Young woodland. No more than 60% of any young woodland may be
cleared. The remaining 40% shall be maintained as permanent open space.
Areas preferred for tree removal include building pads, parking lots,
utility trenches, detention ponds and roads.
(13)
General woodland. No more than 50% of any other woodlands, as
defined below, may be cleared or developed. The remaining 50% shall
be maintained as permanent open space. Areas preferred for tree removal
include building pads, parking lots, utility trenches, detention ponds
and roads.
(14)
Woodlands replacement credit. Subject to satisfying the conditions
set forth in this section, a developer may clear or develop more than
the area otherwise permitted to be disturbed by this article, provided
that the total disturbed woodland or mature woodland area shall not
be increased by more than 50% of the area otherwise permitted to be
disturbed. In no case, however, shall more than 60% of mature woodlands
be disturbed and no more than 75% of other general woodlands be disturbed:
(a)
When a "woodlands replacement credit" is requested, the delineation required pursuant to this article shall be utilized in the preparation of a reforestation plan by a certified landscape architect, forester or naturalist, reflecting the existing diversity of trees on the site. Reforestation shall be at the rate of 500 seedlings similar to the species removed per acre. In addition, additional replacement trees shall be planted for every tree removed with a twelve-inch diameter or greater according to the standards set forth in Subsection E(2) herein. (See illustration, which is included as an attachment to this chapter.[7])
[7]
Editor's Note: Said illustration is included as an attachment
to this chapter.
(b)
The new woodland area shall consist of 1.2 times the surface
acreage of the woodland area disturbed pursuant to this subsection.
(c)
No clearing or timbering of any woodland may occur unless connected
with an approved site plan.
(d)
Individual trees.
[1]
In addition to the woodland protection requirements set forth
above, all healthy trees in excess of 12 inches in diameter at breast
height, wherever located on a site, shall be protected and preserved
to the maximum extent feasible.
[2]
All trees in excess of 12 inches in diameter at breast height
(dbh) that are removed during site preparation or development shall
be replaced with trees of the same species as follows:
[a]
Twelve inches in diameter, replace with six trees
of similar species four inches' diameter at breast height for
every one removed.
[b]
From 12 inches to 18 inches in diameter, replace
with nine trees of similar species four inches' diameter at breast
height for every one removed.
[c]
Greater than 18 inches in diameter, replace with
12 trees of similar species four inches' diameter at breast height
for every one removed.
(15)
Building and site design.
(a)
Roof structures. Rooftops should contribute to the visual continuity
of the corridor and should be considered as a design element that
will be seen from viewpoints at ground level, from other buildings
and from the parkway. The following standards shall apply:
[1]
Buildings having up to and including two stories shall have
fully enclosed roofs. No visible roof-mounted mechanical equipment
shall be allowed.
[2]
Buildings of three stories or more shall also have fully enclosed
roofs or articulated roof forms that express the building and at the
same time shield exposed roof-mounted mechanical systems from view.
(b)
Screening of accessory uses and technical equipment.
[1]
All mechanical equipment and trash collection areas and loading
docks shall be screened from public view and designed so as to be
integral to the site and primary architecture.
[2]
Loading docks, trash collection areas, service entrances and
similar uses shall be oriented away from the parkway whenever possible.
[3]
The visual impact of utilities, data transmission dishes and
related services should be minimized in all developments. Utility
lines shall be installed underground, and all transmitters, switching
boxes and other utility cabinets shall be screened from view of the
parkway.
(c)
Public works and utilities. When it is necessary to construct
public works and utilities such as water towers, high tension electric
lines, microwave relay towers and similar facilities on hillsides,
they should be located so as not to be visible from the parkway or
to reduce their visual impact to the maximum extent possible by locating
off the tops or brows of hills and ridgelines and being constructed
of materials whose color blends in with the surrounding landscape.
F.
Airport Hazard Overlay District.
(1)
Purpose. The purpose of this article is to create an Airport District
Overlay that considers safety issues around the Pittsburgh International
Airport, regulates and restricts the heights of constructed structures
and objects of natural growth, creates appropriate zones, establishing
the boundaries thereof and providing for changes in the restrictions
and boundaries of such zones, creates the permitting process for use
within said zones and provides for enforcement assessment of violation
penalties, an appeals process, and judicial review.
(2)
Relation to other zoning districts. The Airport District Overlay
shall not modify the boundaries of any underlying zoning district.
Where identified, the Airport District Overlay shall impose certain
requirements on land use and construction in addition to those contained
in the underlying zoning district.
(3)
Establishment of airport zones. There are hereby created and established
certain zones within the Airport District Overlay illustrated on the
Pittsburgh International Airport (PIT) Airspace Plan (Drawing 7b of
19 of the PIT Airport Master Plan, as amended), Figures 2 and 3, all
hereby adopted as part of this article and the Official Zoning Ordinance
Map of Robinson Township adopted on March 29, 1993, and subsequently
amended, which include:
(4)
Permit applications.
(a)
As regulated by Act 164 and defined by 14 Code of Federal Regulations 77.13(a) (as amended or replaced), any person who plans to erect a new structure, to add to an existing structure, or to erect and maintain any object (natural or man-made) in the vicinity of the airport shall first notify the Department's Bureau of Aviation (BOA) by submitting PENNDOT Form AV-57 to obtain an obstruction review of the proposal at least 30 days prior to commencement thereof. The Department's BOA response must be included with this permit application for it to be considered complete. If the Department's BOA returns a determination of no penetration of airspace, the permit request should be considered in compliance with the intent of this overlay section. If the Department's BOA returns a determination of a penetration of airspace, the permit shall be denied, and the project sponsor may seek a variance from such regulations as outlined in § 300-52F(5).
(b)
No permit is required to make maintenance repairs to or to replace
parts of existing structures which do not enlarge or increase the
height of an existing structure.
(c)
No notice or review under this section is required for any of
the following construction or alteration:
[1]
Any object that would be shielded by existing structures of
a permanent and substantial character or by natural terrain or topographic
features of equal or greater height, and would be located in the congested
area of a city, town, or settlement where it is evident beyond all
reasonable doubt that the structure so shielded will not adversely
affect safety in air navigation.
[2]
Any antenna structure of 20 feet or less in height except one
that would increase the height of another antenna structure.
[3]
Any air navigation facility, airport visual approach or landing
aid, aircraft arresting device, or meteorological device, of a type
approved by the Administrator, or an appropriate military service
on military airports, the location and height of which is fixed by
functional purpose.
[4]
Any construction or alteration for which notice is required
by any other FAA regulation.
(5)
Variance.
(a)
Any request for a variance shall include documentation in compliance
with 14 Code of Federal Regulations Part 77 Subpart B (FAA Form 7460-1
as amended or replaced). Determinations of whether to grant a variance
will depend on the determinations made by the FAA and the Department's
BOA as to the effect of the proposal on the operation of air navigation
facilities and the safe, efficient use of navigable air space. In
particular, the request for a variance shall consider which of the
following categories the FAA has placed the proposed construction
in:
[1]
No objection: The subject construction is determined to not
exceed obstruction standards and marking/lighting is not required
to mitigate potential hazard. Under this determination, a variance
shall be granted.
[2]
Conditional determination: The proposed construction/alteration is determined to create some level of encroachment into an airport hazard area which can be effectively mitigated. Under this determination, a variance shall be granted contingent upon implementation of mitigating measures as described in § 300-52F(8), Obstruction marking and lighting.
[3]
Objectionable: The proposed construction/alteration is determined
to be a hazard and is thus objectionable. A variance shall be denied
and the reasons for this determination shall be outlined to the applicant.
(b)
Such requests for variances shall be granted where it is duly
found that a literal application or enforcement of the regulations
will result in unnecessary hardship and that relief granted will not
be contrary to the public interest, will not create a hazard to air
navigation, will do substantial justice, and will be in accordance
with the intent of this article.
(6)
Restrictions.
(a)
Use restrictions. Notwithstanding any other provisions of this
article, no use shall be made of land or water within the Airport
District Hazard Overlay in such a manner as to:
[1]
Create electrical interference with navigational signals or
radio communications between the airport and aircraft;
[2]
Make it difficult for pilots to distinguish between airport
lights and others:
[3]
Impair visibility in the vicinity of the airport;
[4]
Create bird strike hazards; or
[5]
Otherwise endanger or interfere with the landing, takeoff or
maneuvering of aircraft utilizing the Pittsburgh International Airport.
(b)
Height restrictions. Any of the following types of construction
or alteration within the boundaries of this overlay district must
comply with applicable FAA and PennDOT regulations regarding height
restrictions in the designated zones:
[1]
Any construction or alteration of more than 200 feet in height
above the ground level at its site.
[2]
Any construction or alteration of greater height than the imaginary
surfaces extending outward and upward from the nearest point of the
nearest runway at Pittsburgh International Airport as regulated by
Act 164 and defined by 14 Code of Federal Regulations Part 77.
[3]
Any highway, railroad, or other traverse way for mobile objects, of a height which would exceed a standard of Subsection B(2) above as adjusted in the following manner:
[a]
Seventeen feet for an interstate highway that is
part of the National System of Military and Interstate Highways where
overcrossings are designed for a minimum of 17 feet vertical distance.
[b]
Fifteen feet for any other public roadway.
[c]
Ten feet or the height of the highest mobile object
that would normally traverse the road, whichever is greater, for a
private road.
[d]
Twenty-three feet for railroad.
[e]
An amount equal to the height of the highest mobile
object that would normally traverse a waterway or any other traverse
way not previously mentioned.
(7)
Preexisting nonconforming uses. The regulations prescribed by this
article shall not be construed to require the removal, lowering, or
other change or alteration of any structure or tree not conforming
to the regulations as of the effective date of this article, or otherwise
interfere with the continuance of a nonconforming use. No nonconforming
use shall be structurally altered or permitted to grow higher, so
as to increase the nonconformity, and a nonconforming use, once substantially
abated (subject to the underlying Zoning Ordinance), may only be reestablished
consistent with the provisions herein.
(8)
Obstruction marking and lighting. Any permit or variance granted pursuant to the provisions of this article may be conditioned according to the process described in § 300-52E(5) to require the owner of the structure or object of natural growth in question to permit the municipality, at its own expense, or require the person requesting the permit or variance, to install, operate, and maintain such marking or lighting as deemed necessary to assure both ground and air safety.