HomeMy WebLinkAbout009 Sewer Peak Hourly Demand LetterPage | 1
SE Engineers
PO Box 10776
Bozeman, MT 59718
01/11/24
Dairy Queen Sewer Peak Hourly & Hourly Domestic Water Demands
The Peak Hourly Demand (PHD) is calculated as follows:
• Building Average Daily Demand (Qave)
o Restaurant, Full Service = 40 Gallon / Seat
(ref: 15A NCAC 02T.0114 Wastewater Design Flow Rates - see attached)
▪ Total Seats = 44
▪ Qave = 44 seats. x (40 gal / seat)
▪ Qave = = 1,760 gallon per day
• Peaking Factor (Qmax/Qave) = (18 + P1/2) / (4 + P½)
(ref: Design Standards and Specifications Policy; City of Bozeman March 2004)
o P = Population in thousands
o P = 44 occupants = 0.044 Thousand of People
o Qmax = ((18 + 0.209) / (4 + 0.209)) x 1,760
o Qmax = 4.33 x 1,760
o Qmax = 7,614 gal/ day
Hourly domestic water demand is based off attached spreadsheet:
Hourly domestic water demand = 13.0 GPM (from spreadsheet) x 60 min/ hour
Hourly domestic water demand = 780 GPH
SE Engineers
Bill Edden, PE
Owner, Mechanical Engineer
Project Name:Dairy
Date 1/11/2024
SE Engineers
PO Box 1491
Three Forks, MT 59752
406-600-8796
Flush Valve = 0, Flush Tank = X X
Static Pressure in Main (PSI)80
Elevation Rise (FT)26
Meter Loss (PSI)7
Backflow Preventor Loss (PSI) 8
Minimum Available Water Pressure (PSI) 53.82
Minimum Required Fixture Pressure (PSI) 15
Maximum Length 250
Developed Length Factor 1.5
Total Developed Length 375
Fixture Qty FU Total FU
Sink 2 2 4
Clothes Washer 0 4 0
Dishwasher (Domestic)0 1.5 0
Drinking Fountain 0 0.5 0
Drinking Fountain Assembly 0 0.75 0
One Hose Bibb 1 2.5 2.5
Each Additional Hose Bibb 1 1 1
Kitchen Sink (domestic)0 1.5 0
Hair wash sink 0 3 0
Lavatory 4 1 4
Mop Basin 1 3 3
Bath/ Shower 0 4 0
Tire Wash 0 5 0
Urinal Public (1.0 GPF)0 4 0
Urinal Assembly (1.0 GPF) 0 5 0
Water Closet Public (1.6 GPF gravity) 2 2.5 5
Water Closet Public (1.6 GPF Flushometer tank) 0 2.5 0
Water Closet Public (1.6 GPF Flushometer valve) 0 5 0
Water Closet Assembly (1.6 GPF gravity) 0 3.5 0
Water Closet Assembly (1.6 GPF Flushometer tank) 0 3.5 0
Water Closet Assembly (1.6 GPF Flushometer valve)0 6 0
19.5
13
2.9813333
1
5.05
4.15
Water Flow Velocity (FPS)
Calculated Main Friction Loss (PSI/100ft)
Project Information
Total Water Demand
Total FU
Total GPM
Allowable Friction Loss Per 100 Feet (PSI)
Water Main Sizing (Input By User)