HomeMy WebLinkAbout6_Icon Apartments_Email exchange with City_06-24-2019 tims@mad-eng.com
From: James R. Nickelson <jnickelson@m-m.net>
Sent: Monday,June 24, 2019 9:56 AM
To: Bob Murray (BMurray@bozeman.net)
Cc: Will Ralph; Matt E. Ekstrom
Subject: FW: Icon Apartments - Revised Sewer Flow Memo
Bob,
Just checking to see if you need any more information on this?
Thanks
James
0 James R. Nickelson, PE
Senior Engineer, Morrison-Maierle
_ %406 M 6824 direct 1 406.579.3108 mobile
From:James R. Nickelson
Sent: Monday, May 20, 2019 10:20 AM
To: Bob Murray<BMurray@BOZEMAN.NET>
Cc: Kevin D.Jacobsen <kjacobsen@m-m.net>; 'Will Ralph' <wralph@blackridgeco.com>;Shawn Kohtz
<SKohtz@ BOZEMAN.NET>
Subject: RE: Icon Apartments- Revised Sewer Flow Memo
Bob and Shawn,
In order to see if the flow monitoring approximates the pumped flow accurately I developed a simplified model
using SewerCad software. The simplified model includes a manhole at Durston/Cottonwood, a manhole at
Durston/Flanders Mill, the flow monitored manhole in Flanders Mill and an outfall. In order to see if the peak
flows shown on the flow monitoring graph on page 3 of the memo were reasonable the model included a base
flow of 150 gpm flowing in at Durston/Cottonwood and a pumped flow of 620 gpm at intervals. The intervals
were set on for 0.02 hours (1.2 minutes) and set to go on every 0.4 hours (2.5 times per hour). The model was
set to iterate at 0.01 hour intervals.
Running the model for 2 hours using the extended period simulation feature, the model results show a peak
flows as follows:
Durston/Cottonwood —770 gpm
Durston/Flanders Mill —234 gpm
Flanders Mill Manhole— 186 gpm
This model information demonstrates that the peak pumped flow of 620 gpm quickly drops as it flows down the
sewer line. As noted in my memo, the volume pumped from the station shows up in the flow monitoring
results.
Let me know if this is adequate information to address the concern.
I can construct a more detailed model with all of the manholes, allocate the flow based on unit counts, etc., if
needed but I am thinking that the information provided with a quick analysis shows that the monitoring data is
within reason.
i
Thanks
James
James R. Nickelson, PE
Senior Engineer, Morrison-Maierle
_ L 406 922 6824 direct 1 406.579.3108 mobile
From: Bob Murray[mailto:BMurray@BOZE MAN.NET]
Sent: Friday, May 17, 2019 11:41 AM
To:James R. Nickelson<inickelson@m-m.net>
Cc: Kevin D.Jacobsen<kiacobsen@m-m.net>; 'Will Ralph' <wralph@blackridgeco.com>;Shawn Kohtz
<SKohtz@ BOZE MA N.N ET>
Subject: FW: Icon Apartments -Revised Sewer Flow Memo
James, see Shawn's comment below. That is one of the things we talked about needing to be addressed. Let me know if
we need to do an additional monitoring to answer that question.
From:Shawn Kohtz<SKohtz@BOZE MAN,NET>
Sent: Monday, May 13, 2019 9:29 AM
To: Bob Murray<BMurray@BOZEMAN.NET>
Subject: FW: Icon Apartments-Revised Sewer Flow Memo
The measured peak flow still doesn't make sense. They note the firm capacity of the Laurel Glen Lift Station as 620 gpm,
but the measured flow is 505 gpm, which includes flows from other areas in addition to the Laurel Glen Lift
Station. Something isn't accurate.
From:James R. Nickelson<inickelson@m-m.net>
Sent: Monday, May 13, 2019 9:14 AM
To: Bob Murray<BMurray@BOZEMAN.NET>
Cc: Kevin D.Jacobsen <kiacobsen@m-m.net>; wralph@blackridgeco.com; Shawn Kohtz<SKohtz@BOZEMAN.NET>
Subject: Icon Apartments-Revised Sewer Flow Memo
Bob,
Attached is the updated memorandum. The memo has been updated to incorporate your comments. As you
predicted, the revised analysis methodology shows that the full buildout of the basin with the full buildout of the
Icon Apartment project can be completed without any offsite sewer line improvements.
Let me know if you have any questions.
Thanks
James
James R. Nickelson, PE
■■ Senior Engineer, Morrison-Maierle
L 406 922.6824 direct 1 406 579.3108 mobile
- V 2880 Technology Blvd W, Bozernan, MT 59718
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