These setbacks from the edge of wetlands are the minimum and
may be extended further if deemed necessary for the protection of
the interests of this chapter by the Commission. These setbacks may
be waived, modified, or altered in extraordinary circumstances if
the petitioner establishes by a preponderance of the evidence that
the project cannot be accomplished with any other design and there
will be minimal adverse impact to the interests of this chapter.
Wetland dependent structures (drains, outfalls, weirs), fences,
and structures necessary for upland access where reasonable alternative
access unavailable
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0-foot setback
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No disturb zone in which there shall be undisturbed natural
vegetation, except for vernal pools shall be
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50-foot setback
100-foot setback
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Driveways, roadways, structures
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75-foot setback
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Aboveground or underground storage of gasoline, oil other fuels
and hazardous materials
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100-foot setback
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Pasture and stables/barns for animals
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100-foot setback
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Plans shall adequately describe the proposed activity and its
effect on wetlands and related water resources and adjoining land
areas. Pre-project and post-project hydrology should remain fundamentally
the same as it pertains to protecting wetlands functions and values.
Of course, some minor degree of change in hydrology is inevitable
in any engineering/construction project, and within reasonable limits,
the Commission shall permit such variation when, in its judgment,
such changes will not produce a significant impact on wetlands functions
and values. The use of aboveground vegetated swales, infiltration
methods, and other low-impact drainage designs will be given preference
over subsurface drainage structures. The following items are set out
as a minimum standard and are not intended to be a complete and final
presentation as to what a plan would show. The applicant may submit,
or be required to submit to the Commission, any additional information
which would assist in the review and which is deemed necessary to
determine the proposed effect on the interests protected by the Harvard
Wetlands Bylaw.
Any revised plans shall be submitted no later than 12:00 noon
on the Thursday prior to the scheduled hearing, unless the hearing
is scheduled on a day other than a Thursday in which case the plans
shall be submitted at least one week prior to the hearing. All revised
plans shall be sent to the Department of Environmental Protection
regional office at the same time for additional review and comment.
All applications shall include:
A. General information required. The applicant upon submission of the
application may be required to provide the following:
(1) All drawings shall be drawn with the title designating the name of
the project, location and names of the person(s) preparing the drawings
and the date prepared, including the latest revision date. The Commission
may require that plans and calculations be prepared and stamped by
a registered professional engineer (PE) or other registered professional
when in its judgment, the complexity warrants this certification.
Registered professional engineers shall indicate the engineering discipline
in which they are certified. Plans depicting proposed drainage systems
must be certified by a registered professional civil engineer.
(2) An eight-and-one-half-inch by eleven-inch photocopy of the U.S.G.S.
quadrangle sheet, showing the location of the proposed project.
(3) An eight-and-one-half-inch by eleven-inch section of the Tax Assessors
map on which the site of the proposed activity is outlined in red.
B. Site plan. The applicant shall submit a site plan, at a scale of
one inch equals not more than 40 feet, showing the following items:
(1) When excavation, fill, or other construction is proposed; existing
and proposed contours (in contrasting symbols) shall be shown in feet
above sea level or relative to a datum with intervals no greater than
two feet. Date of ground survey shall be given.
(2) Delineation of all wetlands, lands subject to flooding, water bodies,
waterways, ditches, creeks, rivers, streams, and ponds, whether natural
or man-made, continuously or intermittently flowing. The upland boundary
of all bordering vegetated wetlands shall also be shown. The 100-year
flood elevation shall be shown.
(3) A delineation of the 100-foot and 200-foot (if required by §
147-4A) buffer zones.
(4) A delineation of all alterations proposed in or having an impact
on wetlands.
(5) Existing stone walls, buildings, rock ridges and outcroppings shall
be shown.
(6) Location, extent, and area of all existing and proposed structures,
roadways, paved areas, septic systems, wells, tanks, and utility easements.
(7) Proposed lowest elevation of cellars or floors.
(8) Existing and proposed location, rim elevation, and invert elevation
of all catch basins, drains, culverts, and other drainage structures
immediately upstream and downstream of the site, as well as those
on-site.
(9) Details and locations for all temporary erosion controls proposed.
(10)
Proposed permanent pollution control devices on site, such as:
hooded catch basins, flow dissipaters, or vegetative buffers.
(11)
Cross-sections showing existing and proposed slope, elevations,
bank, and bottom conditions of each watercourse to be altered. Locations
of cross sections shall be specified.
(12)
Proposed location of any fill material which will be stored
on site.
(13)
The "limit of work" line shall be shown.
(14)
All plans submitted to the Commission for review shall, when
possible, be in color or highlighted with transparent marker pen as
follows:
(b)
Green: fifty-foot setback from wetland line.
(c)
Yellow: seventy-five-foot setback from wetland line.
(d)
Pink: 100-foot (and 200-foot, if required) setback from wetland
line.
(e)
Orange: siltation barrier.
C. Stormwater management. A compliance evaluation is required to demonstrate how the proposed project meets the applicable stormwater management standards identified in this section of the regulations, when triggered. No resource area other than buffer zone, riverfront area, bordering land subject to flooding, or isolated land subject to flooding may be altered or filled for the impoundment, detention, or retention of stormwater and the applicable performance standards for these resource areas under these regulations shall apply to any such alteration or fill. Except as expressly provided in §
147-14C(1) or
(2) below, stormwater runoff from all industrial, commercial, institutional, office, residential, and transportation projects that are subject to regulation under this chapter including site preparation, construction, and redevelopment and all point source stormwater discharges from said projects within any resource area shall be provided with stormwater best management practices to attenuate peak rate and volume of runoff, attenuate pollutants, and to provide a setback from receiving waters and wetlands in accordance with the applicable standards below and the Massachusetts Stormwater Handbook. In project design, the applicant shall consider environmentally sensitive site design and low-impact development techniques to manage stormwater;
(1) The stormwater management regulations set forth at 310 CMR 10.05(6)(k)
to (q) shall apply to any project pursuant to said regulations where
any work is proposed within any bylaw resource area or where a stormwater
discharge is proposed within any resource area, including the buffer
zone. In addition to meeting the 10 stormwater management standards
at 310 CMR 10.05(6)(k), stormwater best management practices shall
be provided to reduce by at least 5%, match or improve the peak runoff
rates and volumes under proposed conditions compared to existing conditions
for the two- and ten-year frequency storm events, and peak runoff
rates and volumes under proposed conditions compared to existing conditions
shall not exceed existing peak runoff rates and volumes for the fifty-
and 100-year frequency storm events. Drainage calculations must include
existing and proposed runoff rates and volumes for the two-, ten-,
fifty-, and 100-year frequency storm events to all site design points
with a narrative summary and summary table and be stamped and signed
by a Registered Professional Engineer. Such calculations shall be
conducted in accordance with standard recognized engineering practices
using rainfall data from the "Extreme Precipitation in New York &
New England" (www.precip.net) developed by Northeast Climate Research
Center at Cornell University or other methods approved by the Commission.
The specific rainfall data to be used in such calculations under these
Regulations are from Harvard Center and are 3.05 inches for the two-year,
twenty-four-hour event; 4.54 inches for the ten-year, twenty-four-hour
event; 6.75 inches for the fifty-year, twenty-four-hour event; 8.02
inches for the 100-year, twenty-four-hour event.
(2) Projects that do not trigger the stormwater management regulations cited in §
147-14C(1) above shall, at a minimum, meet the following stormwater management standards when the proposed project would result in greater than a five-percent increase in impervious surfaces on the site;
(a)
There shall be no new stormwater conveyances that discharge
untreated stormwater directly to or cause erosion within bylaw resource
areas;
(b)
Peak runoff rates and volumes under proposed conditions must be reduced by at least 5% compared to existing conditions for the two- and ten-year frequency storm events and must not exceed existing peak runoff rates and volumes for the fifty- and 100-year frequency storm events. Drainage calculations must include existing and proposed runoff rates and volumes for the two-, ten-, fifty-, and 100-year frequency storm events using the rainfall data provided in §
147-14C(1) above to all site design points with a narrative summary and summary table and be stamped and signed by a registered professional engineer;
(c)
Loss of recharge to the groundwater shall be minimized by infiltration
measures, including, but not limited to, environmentally sensitive
site design, low-impact development techniques, stormwater best management
practices, and good operations and maintenance. This standard shall
be met when the stormwater management system is designed to infiltrate
the required recharge volume based upon soil type in accordance the
Massachusetts Stormwater Handbook. There shall be pretreatment of
stormwater runoff from any impervious surface other than a non-metal
roof prior to infiltration. Documentation from soil test pit(s) excavated
in the area of any proposed infiltration system shall be included
in the filing to demonstrate a minimum of two feet of separation from
the bottom of the proposed system and seasonal high groundwater, and
to confirm the soil type used in the infiltration calculations. In
the case where two feet of separation cannot be achieved or when the
soils do not support infiltration, other stormwater management options
including low impact development techniques shall be considered;
(d)
Site and stormwater management design shall consider the presence
of critical areas. Critical areas are recharge areas for public water
supplies as defined at 310 CMR 22.02 (i.e., Zone I, Zone II, and interim
wellhead protection areas for groundwater sources and Zone A for surface
water sources), Outstanding resource waters and special resource waters
as designated at 314 CMR 4.06, bathing beaches as defined at 105 CMR
445.000, and cold-water fisheries as defined at 314 CMR 9.02 and 310
CMR 10.04. A discharge within the Zone II of a public water supply
or within or near any other critical area requires the use of specific
source control and pollution prevention measures and the use of specific
structural stormwater best management practices identified for such
areas in the Massachusetts Stormwater Handbook. A discharge is near
a critical area if there is a strong likelihood of a significant impact
occurring to said area, considering site-specific factors. Stormwater
discharges to critical areas shall be removed from or set back from
receiving waters or wetlands and shall receive the highest and best
practical method of treatment commensurate with the scope of the proposed
project. There shall be no stormwater discharges to the Zone I of
a public water supply well unless essential to the operation of the
public water supply;
(e)
A construction period erosion and sedimentation control plan
commensurate in scope with the proposed project and its potential
to affect resource areas shall be provided for review and implemented
during construction; and
(f)
An operations and maintenance plan commensurate in scope with
the proposed project shall be provided for review and implemented
post-construction which identifies the responsible party and provides
the inspection and maintenance requirements for all proposed stormwater
system components.