HomeMy WebLinkAbout13 Alderson Water Sewer and Traffic Estimate L7�
ENGINEERING&
L LAND SURVEYING
December 22, 2021
City of Bozeman Engineering Dept.
Attn: Alicia Paz-Solis
20 E. Olive Street
P.O. Box 1230
Bozeman, MT 59771-1230
RE: Water&Wastewater Demand and Traffic Estimate, Alderson V, 806 Alderson Drive,
City of Bozeman Project#21164
Dear Alicia,
The water and sewer demand estimates and trip generation estimate are provided below as
requested in the Site Plan Review Memorandum Dated September 14, 2021.
Sanitary Sewer Demand Estimate:
The Alderson V project proposes a total of 5 dwelling units.
Estimated Average Daily Sewer Flow:
5 dwelling units
2.17 persons/dwelling unit
64.4 gpdpc
(5 units)(2.17 persons/dwelling unit)(64.4 gpdpc)= 699 gpd (0.49 gpm)
Amax 18+P1 thousands)
i2 (P = Population in thds Peaking Factor =Qave — 4+P1/2 p )
Peaking Factor = 1s+(0.010911/2 = 4.41
4+(0.0109) /2
Assumed Infiltration = 150 gallons/acre/day x 0.2256 acres = 33.8 gpd
—> Max. Flow, Qmax = (Qavg x Peaking Factor) + Infiltration
_ (699 gpd x 4.41) + 33.8 gpd = 733 gpd (0.0011 cfs
T: 406.581.4097 I E MCOTTERMAN@CADDISENG.COM PO BOX 11605,BOZEMAN, MT 59719 WWW.CADDISENG.COM
Water Demand Estimate:
Estimated Average Daily Flow:
5 dwelling units
2.17 persons/dwelling unit
170 gpdpc
(5 units)(2.17 persons/dwelling unit)(170 gpdpc)= 1,845 gpd (1.28 gpm)
Estimated Maximum Daily Flow:
Maximum Day to Average Day Ratio of 2.3:1 (Per COB Design Standards)
1,845 gpd x 2.3 = 4,242 gpd (2.95 gpm)
Peak Hour Flow:
Peak Hour to Average Day Ratio of 3:1 (Per COB Design Standards)
1,845 gpd x 3 == 5,534 gpd (3.84 gpm)
Perak Hour Traffic, Trip Generation Estimate:
The 5-plex structure proposed with the Alderson V project fits the ITE definition of Multifamily
(Mid-Rise) Housing (ITE: Land Use Code 221). The 10th Generation ITE Trip Generation Manual
recommends a peak hourly trip generation factor of 0.44 trips per dwelling unit in a general
urban/suburban setting. This equates to a peak hour trip generation of 2.2 trips for the 5 dwelling
units proposed.
If you need any further information to complete your review of this project, please don't hesitate
to contact me.
Sincerely,
77//
/f ,9
Matt Cotter an, P.E., P.L.S.
21033\sewer and traffic calculations.Uocx