35 New England Business Center Drive Suite 140 Andover, MA 01810

35 New England Business Center Drive
                                                                                                               Suite 140
                                                                                                  Andover, MA 01810

Ref:        8979

July 14, 2021

Nashua Planning Board
City of Nashua
229 Main Street
Nashua, NH 03060

Re:         Traffic Impact Study Peer Review Response
            Nashua Landing
            Nashua, New Hampshire

Dear Chairman LeClair and Members of the Planning Board:

Vanasse and Associates, Inc. (VAI) has been retained by BJ’s Wholesale Club to review responses to peer
review comments issued by Hoyle Tanner & Associates, Inc. as part of their peer review of Traffic Impact
Study1 (TIS) for the Nashua Landing mixed-use development project. Specifically, VAI has reviewed the
June 7, 2021 response to comment letter2 and supplemental technical information provided by Fuss &
O’Neill in their response to the Hoyle Tanner & Associates, Inc. peer review. The focus of our review is
the anticipated impact of the Nashua Landing development on traffic operations along Daniel Webster
Highway and the corridors that will provide access to the project, with specific focus on the impacts to
Adventure Way, including access to an approved BJ’s fueling facility whose sole means of access is via the
Adventure Way corridor.

Based on our review of the updated information provided in response to the City’s peer review, the initial
concerns outlined in our prior June 2, 2021 review of the initial TIS remain, that the traffic impacts
associated with the Nashua Landing project will result in significant increases to motorist delays and vehicle
queuing along the Adventure Way corridor, which will result in adverse impacts to motorists entering and
exiting the BJ’s fueling facility as well as other commercial uses along the corridor.

The supplemental information provided by Fuss & O’Neill indicates the trip generation projections for the
project, as outlined in the initial TIS were understated, and assumed an unsupportable level of internal trip
making between the Costco facility and the future Phase II commercial uses, as well as an overestimation
of the pass-by traffic associated with the Costco facility. The supplemental information also indicates that
based on empirical data collected at operational Costco fueling facilities, the Saturday midday traffic
generation exceeds industry data for fueling facilities that were utilized as the basis for the traffic analysis.
Lastly, the updated traffic analyses do not address concerns raised by both VAI and Hoyle Tanner &
Associates, Inc., that the assignment of traffic to the site from Daniel Webster Highway does not accurately
account for the convenience of Adventure Way as a direct route to Costco’s primary parking field, thereby
continuing to underestimate the projected impact of project-related traffic to Adventure Way’s traffic
operations.

1
    Traffic Impact Study- Nashua Landing, Nashua, New Hampshire, Fuss & O’Neill, February 4, 2021.
2   Self-Storage Facility and Costco – Nashua Landing, 2 East Spit Brook Road, BL Companies and Fuss & O’Neill, June 7, 2021

                    www.rdva.com                       (978) 474-8800                    (978) 688-6508

Nashua Planning Board
July 14, 2021
Page 2

The following summarizes our review.

Trip Generation

As noted in our initial review of the Nashua Landing TIS, concern was raised that the trip generation
projections for both Phase I and Phase II of the project were understated due to errors in the calculation of
both the internal and pass-by trips associated with Phase I and Phase II of the project. In response to
comments issued by the peer review consultant, the applicant has provided supplemental information
relative to empirical Costco gas station trips and has adjusted the pass-by and internal capture rate for Phase
I and Phase II of the development. Both adjustments result in higher trip generation than was identified in
the initial TIS and as such the impacts of project-related traffic, as outlined in the TIS, were understated.

It is also noted that the empirical fueling facility data provided by Fuss & O’Neill for the four surveyed
Costco sites revealed that the empirical Saturday midday trip generation was approximately 27 percent
higher, and ranged as much as 67 percent higher than the ITE trip generation data utilized as part of the
initial TIS. Specifically the initial TIS projected 230 peak hour trips on a Saturday midday for the Costco
fueling facility. However, the empirical data provided by the applicant in their response to peer review
comments indicates that the four surveyed Costco facilities averaged 292 Saturday midday peak hour trips,
and ranged as high as 385 Saturday midday peak hour trips. As such, the Saturday midday trip generation
for the Costco fueling facility likely remains understated in the updated analysis.

Trip Assignment

As part of our initial review, concern was raised that the assignment of Nashua Landing trips to Adventure
Way, both associated with Phase I and Phase II of the project, were underestimated due to the convenience
this corridor provides to the primary parking field that serves the Costco development. Specifically,
concern was raised that contrary to the distribution patterns utilized in the TIS, more traffic would use
Adventure Way than projected, with less traffic traveling the more circuitous route to Spit Brook Road to
access either the Costco parking lot or Daniel Webster Highway. This concern was echoed by the City’s
peer review consultant who noted:

‘The Applicant should consider adjusting these distributions as the Adventure Way entrance appears
much more accessible to the primary parking area for Costco where the bulk of the trips will be
generated.’

The applicant’s trip assignment continues to assume that one third of the Phase I (Costco) trips arriving
from Daniel Webster Highway, north of the project, will travel past Adventure Way, which provides the
shortest and most direct route to the Costco parking field, and instead travel a quarter mile further south to
make a less convenient turn onto Spit Brook Road, before reversing direction on site and traveling north
back to the Costco parking field. This assignment results in a significantly longer and more circuitous route
where motorists avoid the direct access to the Costco parking lot via Adventure Way, and travel an
approximate one half mile longer route by continuing to travel south before reversing direction north via
the site’s internal access drive. This assumed distribution pattern likely results in an underestimation of the
actual southbound left-turns that will occur by motorists accessing Costco from the north. As such, the
delays and associated queuing in the southbound left-turn lane, which provides the sole means of access to
the BJ’s facility for customers arriving from the north, are likely understated, and should be reassessed.

It is noted that the applicant acknowledges that all trips arriving and departing to and from the north on
Daniel Webster Highway, associated with Phase II of the project, would use Adventure Way exclusively

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and not continue to the more circuitous route to Spit Brook Road. Given that Adventure Way terminates
at the Costco parking lot, it is expected that a similar distribution pattern would occur for Costco trips as
the applicant has applied for Phase II traffic, with traffic arriving and departing via Daniel Webster Highway
to the north utilizing Adventure Way as the means of access and egress.

The trip assignment also continues to assume that no new traffic associated with the Costco facility would
utilize Adventure Way as a means to access Daniel Webster Highway southbound to Spit Brook Road
westbound. Specifically, the TIS and June 7th response to peer review comments acknowledge that due to
the convenience Adventure Way offers as a means of egress from the Costco parking lot to Daniel Webster
Highway, one third of traffic destined to the south on Daniel Webster Highway would do so by way of
Adventure Way. This amounts to approximately 10 to 14 vehicles per hour, based on the applicant’s
updated trip assignment projections. However, of the 163 to 251 peak hour trips that are projected to exit
the site towards the Route 3 Exit 1 interchange with Spit Brook Road, zero new trips are assigned to
Adventure Way. This trip assignment is inconsistent with the trip distribution patterns utilized by the
applicant for Phase II, which assumed that new trips associated with this phase would utilize Adventure
Way to Daniel Webster Highway southbound, prior to turning right onto Spit Brook Road. Applying the
same one third distribution to the trips destined to Exit 1, this would amount to approximately 54 to 84
additional exiting trips onto Adventure Way, which were not accounted for in the TIS or updated analysis.

It is also noted that the City’s peer review consultant suggested that Adventure Way may be utilized by
local traffic familiar with the area to access Royal Ridge Road as a means of bypassing several intersections
prior to the Exit 1 interchange. The TIA and updated analysis continue to assign zero new trips to Royal
Ridge Road via Adventure Way.

Based on the comments issued in our initial review, which were also noted by the City’s peer review
consultant, concern remains that the assignment of trips to Adventure Way, both arriving from the north
and departing to points south, including to Exit 1 via Spit Brook Road, remain unaddressed with the
potential impacts to Adventure Way underestimated.

Traffic Operations

As noted in our initial June 2, 2021 letter, based on the applicant’s traffic analysis, the impact of the Nashua
Landing project-generated traffic to Adventure Way is projected to result in significant increases to vehicle
delays. Specifically, as documented in the initial TIS, the addition of Phase I traffic results in the westbound
left-turn movement delays increasing from ~52 seconds under 2022 No-Build conditions to ~105 seconds
under 2022 Build conditions. Similarly, during the Saturday midday peak hour, delays for westbound left
turns from Adventure Way are projected to increase from ~65 seconds per vehicle (LOS E) under 2022 No-
Build conditions to ~218 seconds (LOS F) under 2022 Build conditions with Phase I traffic alone. The
addition of Phase II traffic under 2032 Build conditions further exacerbates delays for westbound left-turn
movements, with the TIS analysis indicting left-turn delays will increase to ~125 seconds and ~372 seconds
during the weekday evening and Saturday midday peak hours, respectively. The increase in delays for left-
turns from Adventure Way during the Saturday midday peak, between 2022 No-Build and 2032 Build
Phase II conditions, based on the applicant TIS analysis, amounts to greater than 300 seconds per vehicle,
or approximately 5 minutes of additional delay. Table 1 summarizes the impacts as outlined in the
applicant’s February 4, 2021 TIS and our initial review letter.

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Table 1
PROJECTED DELAYS – DANIEL WEBSTER HIGHWAY AT ADVENTURE WAY

                                       Weekday Evening Peak Hour                                   Saturday Midday Peak Hour
                          2022 No-Build    2022 Build with 2032 Build with           2022 No-Build      2022 Build with 2032 Build with
                            with BJ’s          Phase 1           Phase 2               with BJ’s            Phase 1          Phase 2
    Movement              Fueling Facility Nashua Landing Nashua Landing             Fueling Facility Nashua Landing Nashua Landing

 Adventure Way              51.6 Seconds             105.3 Seconds   124.6 Seconds    64.7 Seconds     217.9 Seconds     372.1 Seconds
 WB LT

Source: Traffic Impact Study – Nashua Landing, Nashua, New Hampshire; Fuss & O’Neill, February 4, 2021.

   As previously noted, the applicant has indicated that the initial TIS understated the impacts of the project,
   with both pass-by rates and internal capture rates utilized that understated the number of external trips and
   new trips that the project would generate. As such, the actual impacts are greater than those summarized
   in Table 1.

   It is noted that the response to peer review comments does not provide a detailed summary of the projected
   delays for all movements at this intersection under either 2022 Build or 2032 Build conditions, based on
   the higher traffic generation. It is customary to include a summary LOS and delay matrix to allow for a
   comparison between No-Build and Build conditions to allow for a determination of project-related impacts.

   Vehicle Queuing

   The applicant has provided an updated vehicle queue analysis based on the SimTraffic simulation model,
   which in general results in lower levels of vehicle queuing than the prior SYNCHRO queue analysis results
   as presented in the initial TIA. The results of the updated queue analysis continue to demonstrate that the
   Nashua Landing project will result in significant increases to queuing along Adventure Way, particularly
   during the Saturday midday peak hour, that will result in the blockage of both the proposed BJ’s driveway
   and opposing shared access drive that is utilized by CVS and the rear entrance to the Best Buy parking
   garage.

   Specifically, based on the applicant’s analysis, the average Saturday midday queue for westbound left-turns
   from Adventure Way, under No-Build conditions (BJ’s only) is expected to extend approximately 89 feet
   on average with maximum queues of approximately 159 feet. This level of queueing would not extend to
   either the BJ’s fueling facility driveway or the shared access driveway utilized by CVS and the rear entrance
   to the Best Buy parking garage.

   The addition of Phase I traffic is projected to increase the average and maximum queue lengths to 266 feet
   and 402 feet, respectively, which will block both driveways under both average and maximum queue
   conditions. The addition of Phase II traffic is projected to increase average and maximum queues to 319
   feet and 408 feet, respectively, which will further exacerbate the impact of queueing on access to BJ’s and
   other commercial driveways along the corridor.

   Conclusion

   As documented in this letter, the updated information provided in the June 7, 2021 response to peer review
   comments does not address the concerns raised in our initial June 2, 2021 review of the TIS prepared for

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the project, particularly with respect to the anticipated impacts to delays and queuing along Adventure Way.
While the applicant has acknowledged that the trip generation projections outlined in the initial TIS were
incorrect and understated, a detailed summary of the projected delays for all movements at the intersection
of Daniel Webster Highway and Adventure Way based on the corrected volumes was not provided.
Furthermore, the analysis continues to utilize trip distribution assignments to Adventure Way that assume
zero new vehicles associated with the Phase I Costco development would utilize Adventure Way as a means
to access Exit 1 via Spit Brook Road, despite assigning Phase II traffic along this exact route.

The results of the applicant’s capacity analyses continue to demonstrate significant increases to delays for
vehicles turning from Adventure Way, resulting in level of service F conditions that would not exist
independent of the Nashua Landing project. Lastly, the results of the updated vehicle queue analyses
indicate Nashua Landing project-related impacts, which are likely understated for the aforementioned
reasons, will result in regular blockage of the BJ’s fueling facility and CVS/Best Buy driveways, during
peak periods, that would not occur absent the Nashua Landing traffic increases.

If you have any questions or need any additional information, please feel free to contact me directly.

Sincerely,

VANASSE & ASSOCIATES, INC.

Shaun P. Kelly
Associate

Enclosure

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