2019.11.14 Staff Report
Conservation Commission Staff Report 1 November 14, 2019
To: Conservation Commission From: Sarah LaValley
RE: Staff Report, November 14 Commission Meeting
5:30 PM - Continuation: Notice of Intent for construction of a 5-unit apartment building, parking
lot and associated stormwater. Ping Geng & Thomas Gu, 25 Maple Ave, Map ID 32C-171
The application proposes construction of five residential units and ten space parking lot in an area
adjacent to the former pre-diversion Mill River. Current conditions are pavement, gravel, areas of
fill, and some vegetation, which is primarily not proposed to be disturbed. Stormwater requirements
will be met through installation of a subsurface chamber with an outfall at the former channel. There
is no stormwater on the site under current conditions. Resource areas include riverfront, bank, and buffer zone. A woodland restoration area, including 12 trees and 18 shrubs, is proposed. Locations
of these are not shown and are proposed to be located in the field. Silt fence is proposed at the limit
of work, which is at its closest point approximately 20 feet from top of bank. Removal of one 40”
dbh sycamore within riverfront is proposed. The project also required planning board review and
approval as a major site plan, which was issued in October.
Application Overview:
[1] The commission first needs to review the Riverfront area on site as well as the submitted plans to
understand what is the degraded area that existed in 1996 and exists now, per the definition of
degraded per 310 CMR 10.58 (5).
DEP Comments:
The Commission confirmed resource area boundaries onsite in 2017 and noted the presence of fill, lack of topsoil, buried bricks and other debris, that existed prior to 1996 according to aerial photographs, and have been on the site likely since the rerouting of the Mill River in the late 1930s.
[2] An improvement over existing conditions is always required for work submitted under 310 CMR
10.58(5). Acceptable improvements include, but are not limited to:
1) Significant net reduction of impervious surfaces;
2) Planting of indigenous plant species;
3) Providing stormwater management demonstrably in excess of what is required per 310 CMR
10.05(6)(k) through (q);
4) Removal and proper disposal of noxious but otherwise legally located materials.
A revised plan that includes a 4,900 sf ‘woodland restoration area’ was submitted. The
Commission should discuss this plan with the applicant to ensure that the standard for improvement is met. The Order should include a condition that prohibits conversion of the restoration area to impervious surfaces or other uses, and also require that a request for certificate of compliance include documentation of planting success after three growing seasons.
[3] Table 1.0 states that all proposed disturbance will be closer than the existing degraded area but on page 5 of 6 it states that no work is closer than the existing degraded area. This should be
clarified. If any work is closer than the existing degraded area, then either 1 to 1 restoration and/or 2
to 1 mitigation is required.
The table includes a typo, work is NOT proposed closer than the existing degraded area.
Conservation Commission Staff Report 2
November 14, 2019
[4] One cannot use streamstats to overcome the perennial presumption of a stream. Please review
310 CMR 10.58(2)(a)1.d.
This is correct, the application presumes that the stream is perennial and includes riverfront area
on plans. Resource area boundaries have already been confirmed by the Conservation Commission.
[5] Please note that the Stormwater Management Standards only apply to the maximum extent practicable.
Noted. The stormwater report demonstrates compliance with the standards.
[6] Underground stormwater chambers are subject to UIC program requirements.
https://www.mass.gov/underground-injection-control-uic
Noted. The underground chamber will also need to be installed in parent material, not fill. A
condition should be added to require this specifically.
Work is proposed within the Protected Zone to bank resource. In the portion of the site that is zoned
Urban Residential C, where buildings are proposed, this zone is 35 feet but can be allowed within the
URC under the Wetlands Ordinance as a project ‘where development includes mitigation measures
that will improve the existing condition of the wetlands or adjacent upland.’ This is accomplished
through stormwater treatment which will for some standards be an improvement over pre-development conditions, and by site restoration. Other standards of the Ordinance do not apply within the URC area. Within the SC zone, where the stormwater outfall, plantings and restoration area are proposed, the Protected Zone is 50 feet, but the work as proposed can be allowed as a
“Project in or affecting protected zones or resource areas containing areas already
Consistency with the Wetlands Protection Act and Northampton Wetlands Ordinance:
degraded or developed.” The work proposed does not exceed the amount of degraded area, and is
located farther from the resource than existing degraded conditions. Bank is not proposed to be
disturbed. Riverfront standards are discussed in the application and the site is proposed to be
improved through restoration, in a supplemental plan filed on 9/26. An alternatives analysis is not
required as a redevelopment of disturbed/degraded riverfront.
Staff Recommendation:
The flared end outlet structure, including riprap, is proposed to be installed within 1 foot of bank
resource. The applicant has indicated that creation of an artificial wetland in lieu of riprap is not
feasible due to elevation and slope from the subsurface basin, but the Commission could discuss
potential improvements over existing conditions in the outflow area with the applicant to be incorporated.
The Commission should also discuss plans for invasive species removal and control on the site, and
add any conditions necessary.
Require final approval of tree and shrub locations prior to installation, to be incorporated into
construction documents.
Prohibit future alteration within the woodland restoration area.
A certificate of compliance shall include assessment of all plantings, any trees or shriubs not
surviving at that time shall be replaced.
Canadian hemlock and American White Ash are proposed as tree replacements, these species should
not be used to due hemlock woolly adelgid and emerald ash borer.
Comments in the ‘stormwater’ section of the Major Site Plan Memo should also be added for
consistency.
The area meets the definition of ‘disturbed and degraded’ riverfront and Protected Zone, and the proposal meets the performance standards of both the WPA and local Ordinance. An Order of
Conditions, including standard conditions and suggested conditions discussed, can be issued.
Conservation Commission Staff Report 3
November 14, 2019
6:15 PM - Continuation: Notice of Intent for residential driveway construction within buffer zone
to wetland resource areas. Timothy Seney, 1087 Westhampton Rd, Map ID 41-70
The applicant has requested a continuation. Continue the hearing, with no discussion to be held
tonight, until December 12 at 6:00 PM Approve Acquisition – Saw Mill Hills, Map ID 21-014