HomeMy WebLinkAbout108-Water and Wastewater Report_03102022
Water and Sewer Memo:
for
NELSON MEADOWS LOT 17
Gallatin County, Montana
March, 2022
Prepared For:
DGB Development, LLC
Prepared By:
Hyalite Engineers, PLLC
Brett Megaard, PE
Page 1
NELSON MEADOWS LOT 17
ENGINEER’S WATER AND SEWER MEMO
Owner: DGB Development, LLC
244 Cirque Dr.
Bozeman, MT 59718-9315
Introduction
This report provides an estimate of the peak-hour sanitary sewer demand as well as the
average and max day demands of domestic water usage for the proposed site development.
The City of Bozeman Design Standards and Specifications (March 2004) was used as the
primary guideline for this stormwater drainage design.
General Design
The proposed development of the site will contain 8 multifamily units, above commercial
space. The eight residential units, as well as the bathrooms serving the commercial
warehouse space, will share a new 1.5” copper water service and 6” SCH 40 PVC sewer
service. The sewer service will be connected to the 8” main that runs down Royal Wolf Road.
The sewer services will be installed at a minimum slope of ¼-inch per foot. Cleanouts will be
provided at each bend as well as at the exterior of the building. The water service will also
run off of the 8” water main that runs down Royal Wolf Road. Water services are to be 4” for
the domestic supply for a fire sprinkler system, on top of the fixture count demand as shown
in the included Fixture Count chart.
Sewer Demands for Building 1 (West)
Assuming an average daily flow of 2.17 people per dwelling with 64.4-gallons per capita per
day:
(2.17 people per dwelling) X (4 dwellings) = 8.68 people
(8.68 people) X (64.4 gallons per person per day) = 559 gallons per day
Using a peaking factor of 4.43 calculated from equation 10-1 from DEQ Circular 2:
(559 gpd) X 4.43 = 2,576 gpd (1.72 gallons per minute)
Water Demands for Building 1 (West)
Assuming 2.17 people per dwelling with an average daily usage of 170-gallons per person:
(2.17 people per dwelling) X (4 dwellings) = 8.68 people
(8.68 people) X (170 gallons per day) = 1,476 gallons per day
Using a maximum day to average day ratio of 2.3:1 from City of Bozeman Design Standards:
(1476 gpd) X 2.3 = 3,394 gallons per day (2.36 gallons per minute)
Page 2
Sewer Demands for Building 2 (East)
Assuming an average daily flow of 2.17 people per dwelling with 64.4-gallons per capita per
day:
(2.17 people per dwelling) X (4 dwellings) = 8.68 people
(8.68 people) X (64.4 gallons per person per day) = 559 gallons per day
Using a peaking factor of 4.43 calculated from equation 10-1 from DEQ Circular 2:
(559 gpd) X 4.43 = 2,576 gpd (1.72 gallons per minute)
Water Demands for Building 2 (East)
Assuming 2.17 people per dwelling with an average daily usage of 170-gallons per person:
(2.17 people per dwelling) X (4 dwellings) = 8.68 people
(8.68 people) X (170 gallons per day) = 1,476 gallons per day
Using a maximum day to average day ratio of 2.3:1 from City of Bozeman Design Standards:
(1476 gpd) X 2.3 = 3,394 gallons per day (2.36 gallons per minute)
Appendix A – Residential Water Service
N E L S O N M E A D O W S L O T 1 7
M A R C H 2 0 2 2
A P P E N D I X
APPENDIX A
RESIDENTIAL WATER SERVICE