HomeMy WebLinkAboutWater and Sewer Report-03.10.251
March 10, 2025
Water and Sewer Demand Report
Gardiner Simmental Lot 1A, Tract 1, Plat J-5-F
This report outlines the water and sewer demands for the project at Gardner-Simmental Lot 1A,
Tract 1. The project proposes a Chick-fil-A restaurant on the eastern portion of the site that will
connect to existing water and sewer mains. The 5.485-acre site is currently B-2 zoning.
1.0 Water Demands
1.1 Proposed Use
The proposed site includes a Chick-fil-A Restaurant with Drive-Through, the restaurant site will
cover approximately 2.43-ac of the total 5.485-ac site. Per Table 3.7 of the COB Water Facility
Plan, a B-2 zoned 2.43-ac site produces approximately 1,713 gpd (@ 705 gpd/ac) and a MDD of
3,414 gpd (@1,405 gpd/ac). The restaurant has provided historical water usage data for peak
hour demand based on their actual water usage in other same size/capacity facilities, which are
as follows:
1.1.1 Restaurant, Domestic
The following peak hour water usage is based on how many fixtures the restaurant will have and
the demand of those fixtures per the IPC Table E.103.3(3):
• Fixture Units Cold Water = 169.50 units
o Peak Hour Demand = 58.5 gpm
Based on this data it is possible to interpolate the Maximum Day Demand at a rate of 44.9 gpm
(58.5*2.3/3)
1.1.2 Restaurant, Fire Flow
The required fire flow for the Fast-Food Restaurant, based on the current IFC, is 152 gpm.
1.1.3 Irrigation
There is an existing well on site that will be utilized for irrigation. No water provided by the city
will be used for irrigation.
1.1.4 Water Use Summary
Per the provided information above, this site with the fast-food restaurant demands an estimated
total peak hour flow of 210.5 gpm (58.5 gpm peak hour + 152 gpm fire flow). Based on the City
of Bozeman facility plan, the MDD is approximately 3,414 gpd (2.37 gpm), or if interpolation
2
from the peak hour demand is used then MDD would more conservatively be estimated at 44.9
gpm.
2.0 Sewer Demands
2.1 Proposed Use
Per DSSP Table V-1, the proposed B-2 zoning produces 2,000 gpd/ac, which equates to average
day demand of 4,860 gpd (5.61 gpm) for the 2.43-ac used of the total 5.485-ac lot. However, we
believe that a more conservative estimate to use would be to assume that the inflows equal the
outflows resulting in a peak hour demand of 58.5 gpm, after accounting for an infiltration rate of
150 gallons per acre per day the result is a sewer design flow rate 58.75 gpm.