HomeMy WebLinkAboutEmail from Att Ford 7 9 25Hi Anna,
Per our t/c please add this email to the ZBA file. It is from VHB to town DPW in response to the two
questions contained in their email of yesterday regarding the Bearses Way Pump Station.
Thank you.
Mike
FORD & FORD ATTORNEYS AT LAW
MICHAEL D. FORD, ESQ.
72 MAIN STREET, P.O. BOX 485
WEST HARWICH, MA 02671
TEL. (508)430-1900 FAX (508)430-9979
EMAIL: mike@fordandfordattorneys.com
From: Jon Moser <jmoser@VHB.com>
Sent: Tuesday, July 08, 2025 5:27 PM
To: Jakubicka, Miroslav <Miroslav.Jakubicka@town.barnstable.ma.us>
Cc: Jackson, Mark <mjackson@nedevelopment.com>; Boule, Andrew
<Andrew.Boule@town.barnstable.ma.us>; Kupfer, James <James.Kupfer@town.barnstable.ma.us>;
Wrobel, Matthew <Matthew.Wrobel@town.barnstable.ma.us>; Beaudoin, Griffin
<Philip.Beaudoin@town.barnstable.ma.us>; Michael Ford <mike@fordandfordattorneys.com>
Subject: RE: [External] RE: Wilkens Lane Sewer Capacity Analysis
Hi Miro,
Thank you for your review and the updated information on the Bearses Way Pump Station rates.
Please see responses in red below, which supports our original analysis that the Bearses Way
Pump Station can handle the new sewer flow generated by Hanover Hyannis II.
Thanks,
Jon
Jon Moser, PE
Project Manager
Licensed in MA
P 617.607.2619
www.vhb.com
From: Jakubicka, Miroslav <Miroslav.Jakubicka@town.barnstable.ma.us>
Sent: Tuesday, July 8, 2025 2:16 PM
To: Jon Moser <jmoser@VHB.com>
Cc: Jackson, Mark <mjackson@nedevelopment.com>; Boule, Andrew
<Andrew.Boule@town.barnstable.ma.us>; Kupfer, James <James.Kupfer@town.barnstable.ma.us>;
Wrobel, Matthew <Matthew.Wrobel@town.barnstable.ma.us>; Beaudoin, Griffin
<Philip.Beaudoin@town.barnstable.ma.us>; Michael Ford <mike@fordandfordattorneys.com>
Subject: [External] RE: Wilkens Lane Sewer Capacity Analysis
Hi Jon,
I'm following up on our discussion from today. As I mentioned earlier, I agree with the sewer collection
system results regarding pipe capacities and its modeling.
On the other hand, the sewer analysis evaluation of the existing Bearses Way pump station assumes
that the pumping capacity of this pump station is around 2,070 gpm per 2017 flow monitoring report
and the existing pump station should have enough pumping capacity.
The provided memo assumes that each pump adds 750 gpm without accounting for any friction losses in
the force main. Based on the listed pumping rates below, the total dynamic head (TDH) of the existing
force should also be included in the calculation.
According to Andy Boule, WPCF Division Supervisor, today's test with all three pumps running at full
speed showed the highest pumping rate of only 1,780 GPM.
Pumping rates for your reference:
1 pump = 750 gpm
2 pumps=1,460 gpm
3 pumps= 1,780 gpm (at highest reading)
a) Can you confirm that the Bearses way pump station, with the above provided pumping rates,
will still operate correctly with this increased sewer flow?
Based on our updated model, the peak flow at the Bearses Way Pump Station is 1,712 GPM
which includes the increased sewer flow from Hanover Hyannis II project. Therefore, the
three pumps at Bearses Way Pump Station, with a 1,780 GPM pumping capacity provided
above, can handle the new sewer generated by Hanover Hyannis II. The model uses
extremely conservative assumptions as follows, which demonstrates the three pumps
provide the needed capacity:
• Peak flows were assumed for each use at a peaking factor of 5.0 with both
upstream pump stations running at the same time. This would not be a typical
condition.
• If daily flows for the entire sewer shed were calculated by dividing the peak flow of
2.46 MGPD by the peaking factor of 5.0, the average daily sewer flow would be
approximately 492,000 GPD. Using TR-16, the estimated peaking factor for the
entire sewer shed is 4.2 on the ‘peak on maximum day’ curve. Using this updated
peaking factor, the total system including Hanover Hyannis II has a peak flow of
1,435 GPD. Under these assumptions, the capacity of 2 pumps can handle the peak
flows.
b) Additionally, assuming we run all three pumps simultaneously all the time means we are
operating without a redundant pump, so if one is down for repair, we would not be able to
adjust the flow during peak conditions. That being said, all the assumptions are extremely
conservative, so this is unlikely to cause an issue.
VHB notes the extremely conservative assumptions in response to comment a) above and
agree with your note this is unlikely to cause an issue. As noted above, using a peak factor
of 4.2, with the assumption both upstream pump stations are constantly running, the
pumping capacity of 2 pumps can handle the peak flows in the event one pump may be
down for repair or maintenance.
Thank you,
Miro Jakubicka, P.E.
Sr. Project Manager- CWMP Designs
Barnstable Department of Public Works
382 Falmouth Road - Hyannis, MA 02601
Cell: (508) 737 3735
miroslav.jakubicka@town.barnstable.ma.us
http://www.townofbarnstable.us/