The Town of Greenburgh finds that:
A. Land development activities and associated increases
in site impervious cover often alter the hydrologic response of local
watersheds and increase: stormwater runoff rates and volumes; flooding;
stream channel erosion; or sediment transport and deposition;
B. Stormwater runoff contributes to increased quantities
of waterborne pollutants, including siltation of aquatic habitat for
fish and other desirable species;
C. Stormwater runoff can carry pollutants into receiving
water bodies and degrade water quality;
D. Clearing and grading during construction tends to
increase soil erosion and add to the loss of native vegetation necessary
for terrestrial and aquatic habitats;
E. Improper design and construction of stormwater management
practices can increase the velocity of stormwater runoff, thereby
increasing streambank erosion and sedimentation;
F. Impervious surfaces allow less water to percolate
into the soil, thereby decreasing groundwater recharge and stream
base flow;
G. Improperly managed stormwater runoff can increase
the incidence of flooding and the level of floods that occur, endangering
property and life;
H. Substantial economic losses can result from these
adverse impacts on the waters of the municipality;
I. Stormwater runoff, soil erosion and nonpoint source
pollution can be controlled and minimized through the regulation of
stormwater runoff from land development activities;
J. The regulation of stormwater runoff discharges from
land development activities in order to control and minimize increases
in stormwater runoff rates and volumes, soil erosion, stream channel
erosion, and nonpoint source pollution associated with stormwater
runoff is in the public interest and will minimize threats to public
health and safety; and
K. Regulation of land development activities by means
of performance standards management and site design will produce development
compatible with the natural governing stormwater functions of a particular
site or an entire watershed and thereby mitigate the adverse effects
of erosion and sedimentation from development.
The purpose of this chapter is to establish minimum stormwater management requirements and controls to protect and safeguard the general health, safety, and welfare of the public residing within this jurisdiction and to address the findings of fact in §
248-2 hereof. This chapter seeks to meet those purposes by achieving the following objectives:
A. Meet the requirements of minimum measures 4 and 5
of the New York State Department of Environmental Conservation State
Pollutant Discharge Elimination System (SPDES) General Permit for
Stormwater Discharges from Municipal Separate Stormwater Sewer Systems
(MS4s), Permit No. GP-02-02, as amended or revised;
B. Require land development activities to conform to
the substantive requirements of the New York State Department of Environmental
Conservation State Pollutant Discharge Elimination System (SPDES)
General Permit for Construction Activities GP-02-01, or as amended
or revised;
C. Minimize increases in stormwater runoff from land
development activities in order to reduce flooding, siltation, increases
in stream temperature, and streambank erosion and maintain the integrity
of stream channels;
D. Prevent increases in groundwater recharge and stream
base flow.
E. Minimize increases in pollution caused by stormwater
runoff from land development activities that would otherwise degrade
local water quality;
F. Minimize the total annual volume of stormwater runoff
that flows from any specific site during and following development
to the maximum extent practicable; and
G. Reduce stormwater runoff rates and volumes, soil erosion
and nonpoint source pollution wherever possible through stormwater
management practices and to ensure that these management practices
are properly maintained and eliminate threats to public safety.
In accordance with § 10 of the Municipal
Home Rule Law of the State of New York, the Town Board of the Town
of Greenburgh has the authority to enact and amend local laws for
the purpose of promoting the health, safety or general welfare of
the Town of Greenburgh and for the protection and enhancement of its
physical environment. The Town Board may include in any such local
law provisions for the appointment of any municipal officer, employees,
or independent contractor to effectuate, administer and enforce such
local law.
For the purposes of this chapter, the following
activities are exempt from review under this chapter:
A. Any land disturbing activity, including excavating
for the construction of an addition to an existing structure, or the
creation of any impervious surface that involves fewer than 500 square
feet of disturbance.
B. Agricultural activity as defined in this chapter.
C. Silvicultural activity, except that landing areas
and log haul roads are subject to this chapter.
D. Routine maintenance activities to an existing stormwater
management facility that disturb less than 500 square feet and are
performed to maintain the original line and grade, hydraulic capacity
or original purpose of a facility.
E. Repairs to any stormwater management practice or facility
deemed necessary by the Stormwater Management Officer.
F. Any part of a subdivision if a plat for the subdivision
was approved by the Town and filed with the Westchester County Clerk,
Division of Land Records on or before the effective date of this chapter.
G. Land development activities for which a building permit
was approved on or before the effective date of this chapter.
I. Installation of fence, sign, telephone, and electric
poles and other kinds of posts or poles.
J. Emergency activity immediately necessary to protect
life, property or natural resources, as determined by the Town Engineer.
K. Activities of an individual engaging in home gardening,
such as growing flowers, vegetables and other plants primarily for
use by that person and his or her family.
The terms used in this chapter or in documents
prepared or reviewed under this chapter shall have the meanings set
forth in this section.
AGRICULTURAL ACTIVITY
The activity of an active farm, including grazing and watering
livestock, irrigating crops, harvesting crops, using land for growing
agricultural products, and cutting timber for sale, but shall not
include the operation of a dude ranch or similar operation, or the
construction of new structures associated with agricultural activities.
APPLICANT
A property owner or agent of a property owner who has filed
an application for a land development activity.
BUILDING
Any structure intended for the shelter, housing or enclosure
of any person, animal, property or substance.
CHANNEL
A natural or artificial watercourse with a definite bed and
banks that conducts continuously or periodically flowing water.
CLEARING
Any activity that removes the vegetative surface cover.
DEDICATION
The deliberate appropriation of property by its owner for
general public use.
DEPARTMENT
The New York State Department of Environmental Conservation.
DESIGN MANUAL
The New York State Stormwater Management Design Manual, most
recent version, including applicable updates, which serves as the
official guide for stormwater management principles, methods and practices.
DEVELOPER
A person who undertakes land development activities.
DISTURBANCE
Removal of vegetation, excavation or fill or any combination
thereof, including the conditions resulting from any excavation or
fill.
EROSION CONTROL MANUAL
The most recent version of the New York Standards and Specifications
for Erosion and Sediment Control Manual, commonly known as the "Blue
Book."
EXCAVATION
Any act by which earth, sand, gravel, rock, or any other
similar material is cut into, dug, quarried, uncovered, removed, displaced
or spread.
FILL
Any act by which earth, sand, gravel, rock or any other material
is deposited, placed, replaced, dumped, transported or moved to a
new location.
GRADING
To adjust the degree of inclination of the natural contours
of the land, including leveling, smoothing, and other modification
of the natural land surface.
HYDRIC SOIL
A soil that is described in the Soil Survey of Putnam and
Westchester Counties, New York (1994) as somewhat poorly drained,
poorly drained or very poorly drained. Under normal circumstances
hydric soils are inundated or saturated to within 16 inches of the
surface during the growing season. Hydric soils exhibit diagnostic
colors or mottled features as described in the Corps of Engineers
Wetlands Delineation Manual (Environmental Laboratory Technical Report
Y-87-1).
IMPERVIOUS SURFACES
The sum of the horizontal area of coverage or footprint of
all buildings, structures, paved areas, patios and other improved
surfaces on a lot preventing natural runoff to percolate into the
soil, measured in square feet. Areas paved with gravel, crushed stone
and other materials used to support vehicles shall be considered impervious
surfaces for the purposes of this chapter. Swimming pools and tennis
courts that are unenclosed shall not be considered impervious surfaces
for the purposes of this chapter.
INDUSTRIAL STORMWATER PERMIT
A State Pollutant Discharge Elimination System permit issued
to a commercial industry or group of industries that regulates the
pollutant levels associated with industrial stormwater discharges
or specifies on-site pollution control strategies.
INFILTRATION
The process of percolating stormwater into the subsoil.
LANDOWNER
The legal or beneficial owner of land, including those holding
the right to purchase or lease the land, or any other person holding
proprietary rights in the land.
MAINTENANCE AGREEMENT
A legally recorded document that acts as a property deed
restriction and provides for long-term maintenance of stormwater management
practices.
MAJOR LAND DEVELOPMENT ACTIVITY
Any land disturbance activity, including but not limited
to clearing, grading, excavating, soil disturbance or placement of
fill that results in land disturbance equal to or greater than 20,000
square feet, or activities disturbing less than a total of 20,000
square feet of land area that is part of a larger common plan of development
or sale even though multiple separate and distinct land development
activities may take place at different times and on different schedules.
MINOR LAND DEVELOPMENT ACTIVITY
For the purposes of this chapter, the following development
activities shall be considered minor projects: any land disturbance
activity, including but not limited to clearing, grading, excavating,
soil disturbance or placement of fill that results in land disturbance
on any single lot equal to or greater than 500 square feet, but less
than 20,000 square feet.
NONPOINT SOURCE POLLUTION
Pollution from any source other than from any discernible,
confined and discrete conveyances and shall include but not be limited
to pollutants from agriculture, silviculture, mining, construction,
subsurface disposal and urban runoff sources.
PHASING
Clearing a parcel of land in distinct pieces or parts, with
the stabilization of each piece completed before the clearing of the
next.
POLLUTANT OF CONCERN
Sediment or a water quality measurement that addresses sediment
(such as total suspended solids, turbidity or siltation) and any other
pollutant that has been identified as a cause of impairment of any
water body that will receive a discharge from the land development
activity.
RECHARGE
The replenishment of underground water reserves.
SENSITIVE AREAS
Cold-water fisheries, shellfish beds, swimming beaches, groundwater
recharge areas, water supply reservoirs, and habitats for threatened,
endangered or special concern species.
STABILIZATION
The use of practices that prevent exposed soil from eroding.
STOP-WORK ORDER
A written order issued by the Building Inspector or Code
Enforcement Officer that requires all construction activity on a site
to be stopped.
STORMWATER
Rainwater, surface runoff, snowmelt and drainage.
STORMWATER HOTSPOT
A land use or activity that generates higher concentrations
of hydrocarbons, trace metals or toxic materials than are found in
typical stormwater runoff, based on monitoring studies.
STORMWATER MANAGEMENT
The use of structural or nonstructural practices that are
designed to reduce stormwater runoff and mitigate its adverse impacts
on property, natural resources and the environment.
STORMWATER MANAGEMENT FACILITY
One or a series of stormwater management practices installed,
stabilized and operating for control of stormwater runoff.
STORMWATER MANAGEMENT OFFICER
The Town Engineer or officer designated by the Town to accept
and review stormwater pollution prevention plans, forward the plans
to the applicable approval authority, inspect stormwater management
practices, and enforce the requirements of this chapter.
STORMWATER MANAGEMENT PRACTICES (SMPs)
Measures, either structural or nonstructural, that are determined
to be the most effective, practical means of preventing flood damage
and preventing or reducing point source or nonpoint source pollution
inputs to stormwater runoff and water bodies.
SURFACE WATERS
Lakes, bays, sounds, ponds, impounding reservoirs, springs,
wells, rivers, streams, creeks, estuaries, marshes, inlets, canals,
the Atlantic Ocean within the territorial seas and all other bodies
of surface water, natural or artificial, inland or coastal, fresh
or salt, public or private (except those private waters that do not
combine or effect a junction with natural surface or underground waters),
which are wholly or partially within or bordering the state or within
its jurisdiction. Storm sewers and waste treatment systems, including
treatment ponds or lagoons, that also meet the criteria of this definition
are not waters of the state. This exclusion applies only to man-made
bodies of water that were neither originally created in waters of
the state (such as a disposal area in wetlands) nor resulted from
impoundment of waters of the state.
WATERCOURSE
Any natural or artificial, intermittent, seasonal or permanent,
and public or private water body or water segment. A water body is
intermittently, seasonally or permanently inundated with water and
contains a discernible shoreline and includes ponds, lakes and reservoirs.
A watercourse includes rivulets, brooks, creeks, streams, rivers and
other waterways flowing in a definite channel with bed and banks and
usually in a particular direction.
WATERWAY
A channel that directs surface runoff to a watercourse or
to the public storm drain.
WETLAND/FRESHWATER WETLAND
All areas that comprise hydric soils and/or are inundated
or saturated by surface or groundwater at a frequency and duration
sufficient to support, and that under normal circumstances do support,
a prevalence of hydrophytic vegetation as defined by the Corps of
Engineers Wetlands Delineation Manual (Environmental Laboratory Technical
Report Y-87-1). Wetland areas include vernal pools, wet meadows, marshes,
swamps, bogs and similar wet areas.