246-696 Audubon Road NOI 2016-07-27
53 Southampton Road • Westfield, MA 01085-5308 • Tel 413.562.1600
www.tighebond.com
N-936-10-01-03 (7100)
July 27, 2016
City of Northampton Conservation Commission
City Hall – Room 11
210 Main Street
Northampton, MA 01060
Re: Audubon Road Utilities and Road Reconstruction Project
MassDEP File #246-696
Dear Members of the Commission:
We are in receipt of regulatory file number and comments with regard to the above-referenced
Notice of Intent (NOI) submitted to the Commission on February 3, 2016 by Tighe & Bond,
Inc. on behalf of the City of Northampton Engineering Department (City). Comments have
been provided by the Massachusetts Department of Environmental Protection (MassDEP)
Western Region Wetlands Program. A copy of the comment letter is provided in Attachment
A, for reference. The comments are also reiterated below in italic font in the order in which
they were received. Our responses follow each comment.
1.1.1 MADEP Comments
MassDEP issued a Notification of Wetlands Protection Act file number and comments on July
20, 2016. MADEP assigned file number WE 246-696 to the NOI and offered the following
comments. The NOI review was completed by Mark Stinson.
The project proposes the replacement of one or more stream crossings, yet does not appear
to conform with the General Performance Standards at 310 CMR 10.54(4)(a)(6) and 310 CMR
10.56(4)(a)(5), which require a full span or properly embedded structure 1.2 times the mean
channel width. Conformance with these General Performance Standards is the primary way
to demonstrate the proposed project complies with and contributes to the protection of the
interests of the Wetlands Protection Act. Alternatively, for the replacement of an existing
crossing and per 310 CMR 10.53(8), the applicant may demonstrate that conformance with
the Massachusetts River and Stream Crossing Standards (Standards) has been achieved to
the maximum extent practicable, and shall consider site constraints in meeting the Standards
– compared to the costs – by evaluating the following criteria: (1) The potential for
downstream flooding; (2) Upstream and downstream habitat (in-stream habitat, wetlands);
(3) Potential for erosion and head-cutting; (4) Stream stability; (5) Habitat fragmentation
caused by the crossing; (6) The amount of stream mileage made accessible by the
improvements; (7) Storm flow conveyance; (8) Engineering design constraints specific to the
crossing; (9) Hydrologic constraints specific to the crossing; (10) Impacts to wetlands that
would occur by improving the crossing; (11) Potential to affect property and infrastructure;
and (12) Cost of replacement.”
As noted above, the proposed project includes the replacement of an existing stream crossing
(i.e., culvert) and, as such, the work complies with the Massachusetts River and Stream
Crossing Standards to the maximum extent practicable per 310 CMR 10.53(8)(a).
The regulatory language set forth at 310 CMR 10.54(4)(a)(6) states that “Work on a stream
crossing shall be presumed to meet the performance standard set forth in 310 CMR
10.54(4)(a) provided the work is performed in compliance with the Massachusetts Stream
Crossing Standards by consisting of a span or embedded culvert in which, at a minimum, the
bottom of a span structure or the upper surface of an embedded culvert is above the elevation
of the top of the bank, and the structure spans the channel width by a minimum of 1.2 times
the bankfull width. This presumption is rebuttable and may be overcome by the
- 2 -
submittal of credible evidence from a competent source. Notwithstanding the
requirement of 310 CMR 10.54(4)(a)5., the impact on bank caused by the installation of a
stream crossing is exempt from the requirement to perform a habitat evaluation in accordance
with the procedures contained in 310 CMR 10.60.”
The regulatory language set forth at 310 CMR 10.56(4)(a)(5) is generally consistent with the
language cited above, and reads “Work on a stream crossing shall be presumed to meet the
performance standard set forth in 310 CMR 10.56(4)(a) provided the work is performed in
compliance with the Massachusetts Stream Crossing Standards by consisting of a span or
embedded culvert in which, at a minimum, the bottom of a span structure or the upper surface
of an embedded culvert is above the elevation of the top of the bank, and the structure spans
the channel width by a minimum of 1.2 times the bankfull width. This presumption is
rebuttable and may be overcome by the submittal of credible evidence from a
competent source. Notwithstanding the requirements of 310 CMR 10.56(4)(a)4., the impact
on Land under Water Bodies and Waterways caused by the installation of a stream crossing
is exempt from the requirement to perform a habitat evaluation in accordance with the
procedures established under 310 CMR 10.60.”
Existing and proposed culvert conditions are presented in the June 2016 NOI at Section 3.1.2
and Table 3-1 (pages 3-1 and 3-2, respectively) and on Sheet 8 (of 13) “Drainage Culvert
Plan and Section” as provided in Appendix A of the NOI. The proposed culvert matches the
existing culvert location/elevation, but improves upon the overall existing condition by
increasing the openness ratio from 0.62 (existing) to 0.76 (proposed) as a result of the
increased cross-sectional area from 18 square feet (sf) to 22 sf due to the increase in interior
height from 3 feet to 4 feet.
Summary of Alternatives for the Day Brook Replacement at Audubon Road Relative to 310 CMR
10.53(8)
Evaluation Criteria Replacement Culvert as Proposed
Potential for downstream flooding No change
Upstream and downstream habitat
(in-stream habitat, wetlands)
Limited downstream habitat due to historical stream
channelization, additional crossings, and proximity of
development
Potential for erosion and head-
cutting
No change
Stream stability No change
Habitat fragmentation caused by
the crossing
Minimal reduction due to small area and proximity of
downstream restrictions; removing upstream barrier
The amount of stream mileage
made accessible by the
improvements
No change (next stream passage barrier is a 36-inch culvert on
private property located approx. 50 lf downstream)
Storm flow conveyance(1) No change
Engineering design constraints
specific to the crossing
Depth of gravity sewer pipe relative to culvert footings;
roadway grades approaching crossing
Hydrologic constraints specific to
the crossing
No change
Potential to affect property and
infrastructure
No change
Cost of replacement $100,000 (approx.)
Per the sample worksheet provided, MassDEP requires that three different stream crossing
alternatives be considered: 1) structure replacement in-kind; 2) a structure that meets the
- 3 -
General Performance Standards; and 3) a structure that complies with the minimum
applicable Massachusetts River & Stream Crossing Standards for replacement crossings,
namely one designed to avoid or mitigate one or all of the following attributes: a) inlet drops;
b) outlet drops; c) flow contraction that produces significant turbulence; d) tailwater
armoring; e) tailwater scour pools; f) physical barriers to fish and wildlife passage. A “No
Action” alternative need not be evaluated. This assessment is required in order to determine
whether the project will require an Individual Massachusetts Clean Water Act Section 401
Water Quality Certificate (WQC) from the MassDEP, per 314 CMR 9.03(1)(c). A project that
is not designed in accordance with the General Performance Standards or with the minimum
applicable Massachusetts River & Stream Crossing Standards for replacement crossings will
require a WQC from MassDEP. Upon receipt of this requested information MassDEP will inform
all parties as to whether an Individual WQC will be required.
As presented in Section 4.2.1 of the June 2016 NOI, the following culvert replacement
alternatives:
• No Action
• Culvert Replacement
• Bridged Crossing
However, as per MassDEP’s comment, the worksheet provided in Attachment B presents the
following alternatives for the benefit of discussion and disclosure:
1. In-kind Culvert Replacement
2. Structure that meets the General Performance Standards
3. Structure that complies with the minimum applicable Massachusetts River & Stream
Crossing Standards for replacement crossings
Design Considerations and Site Constraints
Maintenance and improvement of existing infrastructure requires understanding and
consideration of design alternatives, the environmental regulatory environment, and site
constraints. The Day Brook Culvert at Audubon Road consists of an open-bottom three-sided
concrete box culvert with a span of 6 feet, an interior height of 3 feet, and a total length of
29 feet.
Immediately upstream of the culvert is a field stone wall/weir originally constructed to create
a small impoundment of Day Brook. The impoundment has long since filled in, but Day Brook
flows around the edges of the former impoundment before flowing over the stone wall/weir
and through the culvert at Audubon Road. Immediately downstream of the culvert is a stone-
lined channel that conveys Day Brook approximately 50 feet to a private driveway crossing
with a 36-inch diameter metal culvert.
Existing site constraints at the culvert include the gravity sanitary sewer and roadway grades
approaching the crossing location. As opposed to sewer force mains, the function of gravity
sewers is dependent on proper grades and pipe slopes. Even small adjustments to the
alignment of the sewer could affect its function upstream and downstream of this location.
The depth of the pipe below grade is related to the depth of the concrete footings for the
existing culvert. A change in the footing design dimensions (e.g., larger to support a wider
culvert) would require the reconstruction of the gravity sewer. However, the reconstruction
of the sewer would extend significantly to the east and west to achieve a new proper slope
for the pipe.
- 4 -
Given the site constraints noted above and the stream crossing improvements proposed as
part of the design submitted in the June 2016 NOI, we respectfully suggest that it is within
the Commission’s authority per 310 CMR 10.53(8) to approve the replacement culvert as
proposed.
Compliance with Section 401 of the federal Clean Water Act and its implementing regulations
(314 CMR 9.00) is addressed in Section 4.4.2 of the June 2016 NOI. The culvert replacement
project improves upon the existing conditions relative to the Massachusetts River & Stream
Crossing Standards and meets the minimum criteria for replacement crossings.
ADDITIONAL REQUIREMENTS:
This project proposes a discharge of dredged or fill material into “Waters of the United States”
potentially subject to the federal Clean Water Act. Per the Massachusetts General Permit
(MAGP) issued under the federal Clean Water Act, you may be required to notify the US Army
Corps of Engineers, New England District of this project proposal.
Compliance with the federal Clean Water Act and/or MAGP is addressed in Section 4.4.4 of
the June 2016 NOI.
Based on the information provided in this response, we respectfully rebut the presumptions
at 310 CMR 10.54(4)(a)(6) and 10.56(4)(a)(5), regarding the proposed culvert replacement
project. We look forward to discussing this project with the Commission at its July 28, 2016
public hearing. If the Commission would like to schedule a site visit or has any questions,
please contact Melissa Coady at (413) 572-3224 / MPCoady@tighebond.com or me at (413)
572-3279 / ZPChornyak@tighebond.com.
Very truly yours
TIGHE & BOND, INC.
Zachariah P. Chornyak, PE
Project Manager
Copy: Mark Stinson, MassDEP Western Region, Wetlands Program
David Veleta, P.E., City Engineer, City of Northampton DPW
J:\N\N0936 Northampton DPW\10 - Audubon Road Drain and Water Project\Permitting\NOI\RESPONSE\2016-07-27\1 -
letter.doc.docx
ATTACHMENT A Tighe&Bond
MassDEP File # 246-696 - Audubon Road Utilities and Road Reconstruction Project (Leeds/Northampton)
DATE:July 20, 2016 Municipality NORTHAMPTON
(city/town)
RE: NOTIFICATION OF WETLANDS PROTECTION ACT FILE NUMBER
The Department of Environmental Protection has received a Notice of Intent filed in accordance with the
Wetlands Protection Act (M.G.L. c. 131, §40):
Applicant:
Address:
LOCUS:
CITY OF NORTHAMPTON DPW
125 LOCUST STREET
AUDUBON ROAD
Owner:
Address:
This project has been assigned the following file # :WE 246-0696
Although a file # is being issued, please note the following:
Commissioner
MARTIN SUUBERG
Secretary
MATTHEW A. BEATON
Lieutenant Governor
KARYN E. POLITO
Governor
CHARLES D. BAKER
A FILE NUMBER ONLY INDICATES THAT THE APPLICATION CONTAINS THE MINIMAL
SUBMITTAL REQUIREMENTS AND IS ADMINISTRATIVELY COMPLETE - NOT THAT
THE INFORMATION IN THE APPLICATION IS ADEQUATE FOR ISSUANCE OF AN ORDER
OF CONDITIONS.
436 DWIGHT STREET, SPRINGFIELD, MA 01103 413-784-1100
WESTERN REGIONAL OFFICE
DEPARTMENT OF ENVIRONMENTAL PROTECTION
EXECUTIVE OFFICE OF ENERGY & ENVIRONMENTAL AFFAIRS
COMMONWEALTH OF MASSACHUSETTS
NORTHAMPTON, MA
The project proposes the replacement of one or more stream crossings, yet does not appear to conform with the
General Performance Standards at 310 CMR 10.54(4)(a)(6) and 310 CMR 10.56(4)(a)(5), which require a full span
or properly embedded structure 1.2 times the mean channel width. Conformance with these General Performance
Standards is the primary way to demonstrate the proposed project complies with and contributes to the protection
of the interests of the Wetlands Protection Act. Alternatively, for the replacement of an existing crossing and per
310 CMR 10.53(8), the applicant may demonstrate that conformance with the Massachusetts River & Stream
Crossing Standards (Standards) has been achieved to the maximum extent practicable, and shall consider site
constraints in meeting the Standards, undesirable effects of risk in meeting the Standards, and the environmental
benefit of meeting the Standards—compared to the costs—by evaluating the following criteria:
(1) the potential for downstream flooding; (2) upstream and downstream habitat (in-stream habitat, wetlands); (3)
potential for erosion and head-cutting; (4) stream stability; (5) habitat fragmentation caused by the crossing; (6) the
amount of stream mileage made accessible by the improvements; (7) storm flow conveyance; (8) engineering
design constraints specific to the crossing; (9) hydrologic constraints specific to the crossing; (10) impacts to
wetlands that would occur by improving the crossing; (11) potential to affect property and infrastructure; and (12)
cost of replacement.
This information is available in alternate format. Call Donald M. Gomes, ADA Coordinator at 617-556-1057. TDD# 1-866-539-7622 or 1-617-574-6868.
http://www.mass.gov/dep
Printed on Recycled Paper
CITY OF NORTHAMPTON DPW
125 LOCUST STREET
NORTHAMPTON, MA
Per the sample worksheet provided, MassDEP requires that three different stream crossing alternatives be
considered: 1) structure replacement in-kind; 2) a structure that meets the General Performance Standards; and 3)
a structure that complies with the minimum applicable Massachusetts River & Stream Crossing Standards for
replacement crossings, namely one designed to avoid or mitigate one or all of the following attributes: a) inlet
drops; b) outlet drops; c) flow contraction that produces significant turbulence; d) tailwater armoring; e) tailwater
scour pools; and e) physical barriers to fish and wildlife passage. A “No Action” alternative need not be evaluated.
This assessment is required in order to determine whether the project will require an Individual Massachusetts
Clean Water Act Section 401 Water Quality Certificate (WQC) from the MassDEP, per 314 CMR 9.03(1)(c). A
project that is not designed in accordance with the General Performance Standards or with the minimum applicable
Massachusetts River & Stream Crossing Standards for replacement crossings will require a WQC from MassDEP.
Upon receipt of this requested information MassDEP will inform all parties as to whether an Individual WQC will be
required.
ADDITIONAL REQUIREMENTS:
This project proposes a discharge of dredged or fill material into “Waters of the United States” potentially subject to
the federal Clean Water Act. Per the Massachusetts General Permit (MAGP) issued under the federal Clean Water
Act, you may be required to notify the US Army Corps of Engineers, New England District of this project proposal.
If you have any questions regarding this letter, please contact: MARK STINSON @ (413)-755-2257
Cc: Northampton Conservation Commission, CITY HALL, 210 MAIN STREEET RM 11, Northampton, MA, 01060
Representative: Tighe and Bond, 53 Southampton Road, WESTFIELD, MA, 01085
This information is available in alternate format. Call Donald M. Gomes, ADA Coordinator at 617-556-1057. TDD# 1-866-539-7622 or 1-617-574-6868.
http://www.mass.gov/dep
Printed on Recycled Paper
ATTACHMENT B Tighe&Bond
MassDEP File # 246-696 - Audubon Road Utilities and Road Reconstruction Project (Leeds/Northampton)
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