HomeMy WebLinkAboutWASTE WATER MEMO 2021.9.20
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406.586.0277
tdhengineering.com
234 East Babcock Street , St. 3
Bozeman, MT 59715
06/29/2021
Karl Johnson
City of Bozeman
20 E. Olive St.
Bozeman, MT 59715
RE: MEDICAL EYE SPECIALISTS, WASTEWATER MEMO
Mr. Johnson:
The following information is provided to summarize the wastewater design capacity for the
Medical Eye Specialists (MES) Clinic located in Lot 4 of the Eastlake Professional Center
(EPC) Subdivision.
The Master Site Plan for the EPC Subdivision estimated a total peak flow based on zone
undeveloped land usage for B-2 zoning from the City of Bozeman design standards Table V-
1. The total demand for the subdivision is estimated at 35.7 gpm of which 11.45 gpm is
devoted to lot 4 where the MES clinic is proposed. An equivalent population of 0.14 was
estimated for the development resulting in a peak factor of 4.21.
The following table is referenced from the Master Site Plan draft design guidelines that shows
the design flow rates for Lot 4.
Table 1 Wastewater Flows
PROJECTED WASTEWATER FLOWS
The MES building will be staffed with 55 employees and an additional 53 patients are
conservatively estimated for operations. The flow rate of 9.6 gal/capita/day is used to project
wastewater generated from the development. The estimated rate is an indirect per capita
use that was established for hospital facilities in the 2018 Wastewater Facilities master plan
for the City of Bozeman. Based on the number of employees at the project use rate, the
development will require 1,037 gpd (0.72 gpm). Using the same peak hour factor of 4.21 the
peak flow equates to 3.03 gpm. With the addition of 300 gpd of infiltration on the 2.0-acre
parcel amounts to a total flow of 3.24 gpm. The projected wastewater use demonstrates that
the Eastlake Subdivision has been designed to adequately serve the MES site.
Sincerely,
________________
Alex Edwards, PE
Civil Engineer
Sewer
Segment
Contributing
Area
(Acre)
Total
Flow
(gpm)
Peaking
Factor
Infiltration
(gpm)
Peak
Flow
(gpm)
Required
Pipe Dia.
(in.)
LOT 4 1.93 2.67 4.21 0.20 11.45 8