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Article 11: Interpretation and Definitions
Section 11.5. Terms and Uses Defined
11.4.2. Exceptions and Variations
June 23, 2017
Morrisville, NC
Page 11-34
Unified Development Ordinance
E
NGINEER
,
L
ICENSED
P
ROFESSIONAL
A professional individual licensed by the State of North Carolina to practice in the field of engineering
sciences. Also referred to as a Professional Engineer.
E
NGINEERED
S
TORMWATER
C
ONTROL
A physical device designed to trap, settle out, or filter pollutants from stormwater runoff; to alter or
reduce stormwater runoff velocity, amount, timing, or other characteristics; to approximate the pre-
development
hydrology on a developed site; or to achieve any combination of these goals. Engineered
stormwater control includes physical practices such as constructed wetlands, vegetative practices, filter
strips, grassed swales, and other methods installed or created on real property. “Engineered stormwater
control” is synonymous with “structural practice,” “stormwater control facility,” “stormwater control
practice,” “stormwater treatment practice,” “stormwater management practice,” “stormwater control
measures,” structural stormwater treatment systems,” and similar terms used in this ordinance. It is a
broad term that may include practices that do not require design by a professionally licensed engineer.
E
PHEMERAL
S
TREAM
A feature that carries only stormwater in direct response to precipitation with water flowing only during
and shortly after large precipitation events. An ephemeral stream may or may not have a well-defined
channel, the aquatic bed is always above the water table, and stormwater runoff is the primary source
of water. An ephemeral stream typically lacks the biological, hydrological, and physical characteristics
commonly associated with the continuous or intermittent conveyance of water.
E
VERGREEN
Plant material that retains its leaf material year-round.
E
XISTING
D
EVELOPMENT
Development not otherwise exempted by this ordinance that meets one of the following criteria:
It either is built or has established a statutory or common-law vested right as of the effective date
of this ordinance; or
It occurs after the effective date of this ordinance, but does not result in a net increase in built-upon
area and does not decrease the infiltration of precipitation into the soil.
E
XISTING
M
ANUFACTURED
H
OME
P
ARK OR
M
ANUFACTURED
H
OME
S
UBDIVISION
For purposes of floodplain management, a manufactured home park or subdivision for which the
construction of facilities for servicing the lots on which the manufactured homes are to be affixed
(including at a minimum, the installation of utilities, either final site grading or the pouring of concrete
pads, and the construction of streets) was completed before the original effective date of the floodplain
management regulations adopted by the community.
E
XISTING
T
REE
C
ANOPY
Tree canopy that existed for at least two years prior to development as evidenced by the aerial
photography and/or satellite imagery on file with or approved by the Town of Morrisville Planning
Department.
E
XPANSION
An increase in the floor area of an existing structure or building, or the increase of area of a use.
E
XTERIOR
I
NSULATION AND
F
INISH
S
YSTEM
(EIFS)
Multi-layered system of Styrofoam panels typically adhered to wood or gypsum sheathing and finished
with a waterproof resin.