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Demands.Docx
INTRODUCTION
The Pines, Phase 2 Site Plan is a proposed apartment development located on Tract 2A of [Plat F1-
D]. The proposed layout consists of one 12-unit apartment building, a drive access, a parking area,
and related stormwater and landscaping areas. The property is located within the City of Bozeman
limits and is currently zoned R-4.
The property is fronted on one side by South 19th Ave, water and sanitary sewer mains are located
within South 19th Ave. and water/sewer services are proposed to serve the development as shown
on civil sheet C2.1.
Water Distribution System Demands
The design parameters used herein are according to the City of Bozeman Design Standards and
Specifications Policy (DSSP) dated May 2017. The following calculations are presented to the
City of Bozeman to satisfy the requirement that the water main must be adequately sized to
provide maximum daily demand plus fire flow and the peak hourly demand. The proposed
building on the site is considered Group R-2 per International Fire Code (IFC) Section 202, and
therefore requires 1500 gpm as minimum available fire flow.
Average Daily Residential Usage = 170 gallons per capita per day
Average Population Density = 2.11 persons/dwelling unit
Minimum Fire Hydrant Flow = 1,500 gpm
Residual Pressure Required = 20 psi for Fire Flow
Average Day Demand (Peaking Factor = 1.0)
Maximum Day Demand (Peaking Factor = 2.3)
Peak Hour Demand (Peaking Factor = 3.0)
Water Demands (12 dwelling units)
Average Day Demand = 12 d.u. x 2.11 persons/d.u. x 170 gpcpd = 4,304 gpd = 2.99 gpm
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Demands.Docx
Maximum Day Demand = 2.99 gpm x 2.3 = 6.88 gpm
Peak Hour Demand = 2.99 gpm x 3.0 = 8.97 gpm
Total Design Demand = 6.88 gpm + 1500 gpm = 1,506.88 gpm
The total design demand is equal to maximum demand plus fire flow, which was found to be
1,506.88 gpm. From hydrant data provided by the City of Bozeman, all hydrants hydraulically
connected to the main servicing the site can meets and exceeds the total design demand flow at the
minimum residual pressure. The table below summarizes the interpolated minimum available flow
at 20 psi. The complete hydrant data and a map of the hydrants are included in Appendix A.
Hydrant Data Summary Table
Hydrant ID
Residual
Pressure
Available
Flow
PSI GPM
Hydrant #346 20 8354.11
Hydrant #348 20 17110.00
Hydrant #349 20 9115.12
Hydrant #668 20 7931.72
Sanitary Sewer Design Load
The population estimates of 2.11 people per dwelling unit, and residential flow rate of 89 gpcd,
and infiltration rate of 150-gallons/acre/day used herein are according to the City of Bozeman
Design Standards and Specifications. The peaking factor for the design area is determined using
the formula provided in the City of Bozeman Design Standards and Specifications.
Using the city average of 2.11 persons per household the equivalent population is calculated.
Connection:
Equivalent Population = (2.11 persons/dwelling unit)(12 units) = 25.32 persons
Harmon Formula: Peaking Factor = (18 + P0.5)/(4 + P0.5)
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Demands.Docx
where: P = Population in thousands
Peaking Factor = (18 + 0.025320.5)/(4 + 0.025320.5)
Peaking Factor = 4.366
Assumed infiltration rate = 150 gallons/acre/day = 150 (0.440 acres) = 66 gal/day
The peak flow rate is calculated by multiplying the City's design generation rate of 89 gallons per
capita per day by the population, multiplying by the peaking factor, and adding the infiltration rate:
Peak Flow Rate = 89 gpcpd (25.32 persons) (4.366) + 66 gpd = 9,905 gpd
= 6.88 gpm
= 0.015 cfs
APPENDIX A
4,5140.1
Miles
This product is for informational purposes and may not have been prepared for, or be suitable for legal, engineering, or
surveying purposes. Users of this information should review or consult the primary data and information sources to
ascertain the usability of the information. Feet
5260
Legend
263
Location
526
IMEG
Pines Phase II
01/02/2025
Created By:
Created For:
Date:
Hydrant Map
Fire Hydrants
Mains
Active
Abandoned
Proposed
Application Received
On Hold
Initial Review
In Review
Public Notice
Final Review
Street Names
City Limits
World Imagery
Low Resolution 15m Imagery
High Resolution 60cm Imagery
High Resolution 30cm Imagery
Citations
1.2m Resolution Metadata
GIS Hydrant #
Available Flow
(gpm)
Residual
Pressure (psi)
346
0 104.65
200 104.24
400 103.77
600 103.2
800 102.53
1,000.00 101.76
1,200.00 100.9
1,400.00 99.96
1,600.00 98.92
1,800.00 97.81
2,000.00 96.61
2,200.00 95.33
2,400.00 93.98
2,600.00 92.54
2,800.00 91.03
3,000.00 89.44
3,200.00 87.78
3,400.00 86.04
3,600.00 84.22
3,800.00 82.34
4,000.00 80.37
4,200.00 78.34
4,400.00 76.23
4,600.00 74.04
4,800.00 71.79
5,000.00 69.47
5,200.00 67.07
5,400.00 64.6
5,600.00 62.06
5,800.00 59.45
6,000.00 56.77
6,200.00 54.03
6,400.00 51.2
6,600.00 48.31
6,800.00 45.36
7,000.00 42.34
7,200.00 39.24
7,400.00 36.08
7,600.00 32.85
7,800.00 29.55
8,000.00 26.17
8,200.00 22.72
8,400.00 19.19
Hydrant Curve
8,600.00 15.61
8,800.00 11.96
9,000.00 8.24
9,200.00 4.45
9,400.00 0.59
9,430.58 0
0
20
40
60
80
100
120
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000Residual Pressure (psi)Available Flow (gpm)
Hydrant Curve
346
Data Disclaimer: Water distribution information is calculated using hydraulic modeling
software and is subject to variation. Actual field conditions may vary. This information
is provided to the requestor for evaluation purposes only, without warranty of any
kind, including, but not limited to any expressed or implied warranty arising by
contract, stature, or law. In no event regardless of cause, shall the City be liable for
any direct, indirect, special, punitive or consequential damages of any kind whether
such damages arise under contract, tort, strict liability or inequity.
GIS Hydrant #
Available Flow
(gpm)
Residual
Pressure (psi)
348
0 104.07
200 103.79
400 103.48
600 103.14
800 102.79
1,000.00 102.42
1,200.00 102.03
1,400.00 101.62
1,600.00 101.2
1,800.00 100.76
2,000.00 100.31
2,200.00 99.85
2,400.00 99.36
2,600.00 98.86
2,800.00 98.34
3,000.00 97.8
3,200.00 97.25
3,400.00 96.68
3,600.00 96.1
3,800.00 95.49
4,000.00 94.88
4,200.00 94.24
4,400.00 93.59
4,600.00 92.93
4,800.00 92.25
5,000.00 91.55
5,200.00 90.84
5,400.00 90.1
5,600.00 89.36
5,800.00 88.59
6,000.00 87.81
6,200.00 87.02
6,400.00 86.21
6,600.00 85.38
6,800.00 84.54
7,000.00 83.68
7,200.00 82.81
7,400.00 81.92
7,600.00 81.01
7,800.00 80.1
8,000.00 79.16
8,200.00 78.19
8,400.00 77.2
Hydrant Curve
8,600.00 76.2
8,800.00 75.19
9,000.00 74.16
9,200.00 73.12
9,400.00 72.05
9,600.00 70.98
9,800.00 69.88
10,000.00 68.77
10,200.00 67.65
10,400.00 66.51
10,600.00 65.35
10,800.00 64.19
11,000.00 63
11,200.00 61.8
11,400.00 60.59
11,600.00 59.36
11,800.00 58.11
12,000.00 56.86
12,200.00 55.57
12,400.00 54.29
12,600.00 52.99
12,800.00 51.67
13,000.00 50.34
13,200.00 48.99
13,400.00 47.63
13,600.00 46.25
13,800.00 44.86
14,000.00 43.45
14,200.00 42.1
14,400.00 40.65
14,600.00 39.15
14,800.00 37.68
15,000.00 36.2
15,200.00 34.72
15,400.00 33.2
15,600.00 31.67
15,800.00 30.14
16,000.00 28.58
16,200.00 26.64
16,400.00 24.91
16,600.00 23.38
16,800.00 22.23
17,000.00 20.77
17,200.00 19.37
17,400.00 17.92
17,600.00 16.22
17,800.00 14.81
0
20
40
60
80
100
120
0 2000 4000 6000 8000 10000 12000 14000 16000Residual Pressure (psi)Available Flow (gpm)
Hydrant Curve
348
Data Disclaimer: Water distribution information is calculated using hydraulic modeling
software and is subject to variation. Actual field conditions may vary. This information
is provided to the requestor for evaluation purposes only, without warranty of any
kind, including, but not limited to any expressed or implied warranty arising by
contract, stature, or law. In no event regardless of cause, shall the City be liable for
any direct, indirect, special, punitive or consequential damages of any kind whether
such damages arise under contract, tort, strict liability or inequity.
GIS Hydrant #
Available Flow
(gpm)
Residual
Pressure (psi)
349
0 109.47
200 109.06
400 108.61
600 108.09
800 107.48
1,000.00 106.79
1,200.00 106.02
1,400.00 105.17
1,600.00 104.23
1,800.00 103.22
2,000.00 102.14
2,200.00 100.98
2,400.00 99.75
2,600.00 98.45
2,800.00 97.08
3,000.00 95.63
3,200.00 94.12
3,400.00 92.54
3,600.00 90.89
3,800.00 89.17
4,000.00 87.39
4,200.00 85.54
4,400.00 83.62
4,600.00 81.64
4,800.00 79.6
5,000.00 77.49
5,200.00 75.31
5,400.00 73.07
5,600.00 70.76
5,800.00 68.4
6,000.00 65.97
6,200.00 63.47
6,400.00 60.91
6,600.00 58.3
6,800.00 55.62
7,000.00 52.88
7,200.00 50.07
7,400.00 47.2
7,600.00 44.28
7,800.00 41.29
8,000.00 38.22
8,200.00 35.09
8,400.00 31.9
Hydrant Curve
8,600.00 28.65
8,800.00 25.35
9,000.00 21.98
9,200.00 18.54
9,400.00 15.06
9,600.00 11.51
9,800.00 7.9
10,000.00 4.23
10,200.00 0.51
0
20
40
60
80
100
120
0 2000 4000 6000 8000 10000 12000Residual Pressure (psi)Available Flow (gpm)
Hydrant Curve
349
Data Disclaimer: Water distribution information is calculated using hydraulic modeling
software and is subject to variation. Actual field conditions may vary. This information
is provided to the requestor for evaluation purposes only, without warranty of any
kind, including, but not limited to any expressed or implied warranty arising by
contract, stature, or law. In no event regardless of cause, shall the City be liable for
any direct, indirect, special, punitive or consequential damages of any kind whether
such damages arise under contract, tort, strict liability or inequity.
GIS Hydrant #
Available Flow
(gpm)
Residual
Pressure (psi)
668
0 104.26
200 103.91
400 103.44
600 102.84
800 102.13
1,000.00 101.33
1,200.00 100.42
1,400.00 99.41
1,600.00 98.31
1,800.00 97.12
2,000.00 95.84
2,200.00 94.47
2,400.00 93.01
2,600.00 91.47
2,800.00 89.83
3,000.00 88.11
3,200.00 86.3
3,400.00 84.41
3,600.00 82.44
3,800.00 80.38
4,000.00 78.24
4,200.00 76.02
4,400.00 73.72
4,600.00 71.34
4,800.00 68.87
5,000.00 66.32
5,200.00 63.7
5,400.00 60.99
5,600.00 58.21
5,800.00 55.34
6,000.00 52.4
6,200.00 49.38
6,400.00 46.29
6,600.00 43.11
6,800.00 39.86
7,000.00 36.52
7,200.00 33.12
7,400.00 29.64
7,600.00 26.08
7,800.00 22.45
8,000.00 18.73
8,200.00 14.93
8,400.00 11.05
Hydrant Curve
8,600.00 7.1
8,800.00 3.08
0
20
40
60
80
100
120
0 1000 2000 3000 4000 5000 6000 7000 8000 9000 10000Residual Pressure (psi)Available Flow (gpm)
Hydrant Curve
668
Data Disclaimer: Water distribution information is calculated using hydraulic modeling
software and is subject to variation. Actual field conditions may vary. This information
is provided to the requestor for evaluation purposes only, without warranty of any
kind, including, but not limited to any expressed or implied warranty arising by
contract, stature, or law. In no event regardless of cause, shall the City be liable for
any direct, indirect, special, punitive or consequential damages of any kind whether
such damages arise under contract, tort, strict liability or inequity.