Atwood North BLSF Letter 6-22-2017
53 Southampton Road • Westfield, MA 01085-5308 • Tel 413.562.1600
www.tighebond.com
H-1363-6-1
June 21, 2017
Sarah LaValley
Conservation, Preservation and Land Use Planner
Northampton Office of Planning and Sustainability
City Hall, 210 Main Street, 2nd Floor
Northampton MA, 01060
Re: Hospitality North – Revised BLSF Calculations
Dear Sarah and Members of the Commission:
At the June 8, 2017 public hearing for the Order of Conditions (OOC) Amendment Request
for the Hospitality North project, it was noted that the Compensatory Flood Storage
calculations, as presented, did not meet the performance standard for Bordering Land
Subject to Flooding (BLSF) as referenced in 310 CMR 10.57(4)(a). As such, Tighe & Bond
herein provides revised calculations for the Commission’s use.
It should be noted that the previously issued calculations in the March 2017 OOC
Amendment Request did not include quantity units, which resulted in confusion in the
comparison. The revised calculations, presented below, indicate the available area at each
elevation, and the associated flood volume for both existing conditions (prior to building
demolition) and the proposed conditions site.
The attached calculations, stamped by me, have been created using AutoCAD Surface
Modeling to define the surfaces (existing and proposed) then that information was analyzed
using the average end area method of calculating the storage volume available at each
elevation on the site within the 100 year flood plain. The attached analysis shows that the
proposed flood storage exceeds the existing flood storage at every incremental elevation.
Using this method, we were able to duplicate the existing flood storage volumes that were
presented and approved in the original Notice of Intent in 2013.
If you have any additional questions, please do not hesitate to reach me by email at
BSHuntley@tighebond.com, or by phone at 413-875-1301.
Very truly yours,
TIGHE & BOND, INC.
Brian Huntley, P.E.
Project Manager
Copy: Eileen O’Leary Sullivan, Atwood Partners, LLC
Travis Ward, Development Associates
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