HomeMy WebLinkAboutPALY_Plumbingletter_18plex_04-28-2020Page | 1
SE Engineers
PO Box 10776
Bozeman, MT 59718
04/28/20
Palisades 18-Plex Sewer Peak Hour Demand
The Peak Hourly Demand (PHD) is calculated as follows:
• Peaking Factor (Qmax/Qave) = (18 + P1/2) / (4 + P½)
o P = Population in thousands
o P = 63 people = 0.063 Thousand of People
o Qmax/Qave = (18 + 0.251) / (4 + 0.251) = 18.251 / 4.251 = 4.29
o Qmax/Qave = 4.29
• Building Maximum Daily Demand (MDD)
o Residential = (# units) X (People per Unit) X (100 GPD/Person)
▪ (18 Units) x (3.5 people per unit) x (100 GPD/ Person)
o ADD = 6,300 GPD
• Peak Hourly Demand (PHD)
o Peak Hourly Demand = (Peaking Factor (Qmax/Qave) X MDD) / 24 hours/ day
o Peak Hourly Demand = 4.29 x 6,300 GPD / 24 hr/day
o Peak Hourly Demand = 1,126 GPH
SE Engineers
Bill Edden, PE
Owner, Mechanical Engineer