HomeMy WebLinkAbout12 - Design Report - Town Pump - Baxter & 19th - Water Water Main Extension Engineer's Report
Town Pump — Baxter Lane and North 19t" Avenue
February 2012
Submitted to:
City of Bozeman Engineering Department
20 East Olive
Bozeman, MT 59715
Montana Department of Environmental Quality
Permitting and Compliance Division
Public Water and Subdivisions Bureau
PO Box 200901
Helena, MT 59620-0901
Prepared by:
Stahly Engineering and Associates
7585 Shedhorn Drive
Bozeman, MT 59718
(406) 522-9526
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Engineer's Report
Contents
Note: The Engineer's Report format for the Town Pump Water Main Extension
follows DEQ-1 organization. Additional information required by the City of
Bozeman Design Standards is added where required.
Report Narrative
1.1.1 General information
1.1.2 Extent of water works system
1.1.3 Alternate plans
1.1.4 Site conditions
1.1.5 Water use data
1.1.6 Flow requirements
1.1.7 Sewage system available
1.1.8 Sources of water supply
1.1.9 Proposed treatment processes
1.1.10 Waste disposal
1.1.11 Automation
1.1.12 Project Sites
1.1.13 Financing
1.1.14 Future Extensions
Figures and Tables
Figure 1. Vicinity Map (included separately)
Figure 2. Water Distribution System Map (included separately)
Table 1. Estimated Water Use
Water Mains 1 3/22/2012
1.1.1 General Information
The proposed new Town Pump is located within the City of Bozeman at
5851 East Baxter Lane. The site is comprised of Lot 1 B of Gardner
Simmental Plaza Subdivision owned by Town Pump with a total acreage
of 4.03 acres. The site is currently occupied by the existing Anderson Pre-
cast building and storage yard. The current building will be demolished
prior to construction of the proposed Town Pump.
The property owner's contact information is:
Town Pump, Inc.
c/o Dan Sampson, Construction and Development Manager
600 South Main Street
Butte, MT 59701
Water supply and wastewater treatment will be provided by the City of
Bozeman's municipal systems. The system owner's contact information
is:
City of Bozeman Public Service Department
Debra Arkell, Director
PO Box 1230
Bozeman, MT 59771-1230
The location of the proposed Town Pump is shown on the Vicinity Map in
Figure 1 included separately at the back of this report.
1.1.2 Extent of Water Works System
Water supply to the existing structure at the site is provided from an
existing 12" water main in Baxter Lane. This main will supply the
proposed town pump with water supply via a 4"fire service line and a 2"
domestic service line. A 1" water line will run from the building to the RV
dump location for use at that location. An 8" water main extension is
proposed on the east side of the property and extends approximately 285
feet to the north from the existing 12" main located in Baxter Lane. This
extension will end with a fire hydrant. The proposed water supply layout
can be seen on Figure 2 attached to this report. Additional fire hydrants
are located at the southeast corner of the intersection of Baxter Lane and
North 19t" Avenue and the Southwest corner of the intersection of Baxter
Lane and Commerce Way.
Existing pressure conditions were obtained from the City of Bozeman's
Water Facility Plan. Water junction J-1661 in the model indicates a steady
state pressure of 107 psi. Extension from this junction to the north 285
Water Mains 2 3/22/2012
feet will have little influence on this steady state pressure and this steady
state pressure indicates water pressure and flow are sufficient for this
extension.
1 .1.3 Alternate Plans
Due to the project's location within the City of Bozeman, extension of
public mains was the only water supply alternative.
1 .1.4. Site Conditions
The site is typical of Bozeman with fine grained soils overlying gravel
deposits. Geotechnical borings have determined the depth to gravel
ranges from 5 to 6 feet. Estimated depth to groundwater obtained from
the geotechnical borings is 3 feet. If mains are installed during high
groundwater times dewatering may be required.
1.1.5. Water Use Data
Water use for the proposed Town Pump was estimated using Table 5-1 of
DEQ-4 for stores. Estimates on customer volume and employee counts
were based on previous similar Town Pump stores. Estimated water
usage for the proposed Town Pump is in Table 1 below. The City of
Bozeman water system model indicates the system is capable of
supplying this proposed use and this lot is included in the service are in
the City of Bozeman Water Facility Plan.
TABLE 1. Estimated Water Use-Town Pump
User Class Proposed Town Pump
Customer volume 500
-Average Day Flow d/customer 3
Subtotal Inmate Water Use 1,500
Staff Population 25
-Average Day Flow d/sta 10
Subtotal Staff Water Use 2,500
-Average Day Flow d 4,000
-Peaking Factor to Maximum Day 2.5
Maximum Day Flow d 10,000
Maximum Day Flow m 6.9
-Peaking Factor to Maximum Hour 3.0
Maximum Hour Flow m 8.3
Water Mains 3 3/22/2012
Fire flow requirements are based on the Uniform Fire Code. The hydrant
flow is determined using Table H.5.1 of the Uniform Fire Code. An 8,200
sq ft Type V-B building requires a fire flow of 2,500 gpm. The fire
department is allowing a 75% reduction due to the fire sprinkler system
down to the minimum required fire flow of 1,500 gpm. The total fire flow
required from the hydrants and sprinkler system is 1500gpm.
1 .1.6. Flow Requirements
The water main extension for the proposed Town Pump is 285 feet long.
Because of the size and pressures (107 psi steady state) in the existing
12" water main, a hydraulic analysis was not performed. The head loss
through the pipe extension and hydrant assembly will not significantly
change from the existing conditions.
1.1.7. Sewage System Available
Sewer service will be provided by city mains. The proposed Town Pump
will be connected to existing sewer mains located in Baxter Lane. Where
new water and sewer mains are parallel a 10-foot separation will be
provided between pipes. Where water mains cross sewer mains 18" of
vertical separation will be provided.
1.1.8. Sources of Water Supply
This section is not applicable.
1.1.9 Proposed Treatment Process
This section is not applicable.
1 .1.10 Waste Disposal
This section is not applicable.
1.1.11 Automation
This section is not applicable.
1.1.12 Project Sites
This section is not applicable.
Water Mains 4 3/22/2012
1 .1.13 Financing
This section is not applicable.
1.1 .14 Future Extensions
This section is not applicable.
Water Mains 5 3/22/2012
Town Pump - Baxter Lane and North 19th Avenue
Water Extension Capacity Calculations
Total Area Served= 6.31 acre (Includes future development)
Community Commercial(Table V-2)= 2400 gal/acre/day
Irrigation Demand(assume 1 acre at IVday)= 18.82 gal/min
Total Daily Flow= 42245 gal/day
Total Daily Flow= 1760 gal/hr
Total Daily Flow= 29.3 gal/min
Max Day Flow(2.3.1)= 67.5 gal/min
Required Fire Flow(IFC 2009)= 1500 gal/min (min allowed w/sprinklers)
Total Max Day Plus Fire Flow= 1567.5 gal/min
8-inch Extension Calculations at Total Max Day Pius Fire Flow
Use Hazen-Williams
Velocity in 8-inch pipe at 1568 gpm= 10.0 fUsec less than 15 ft/sec so ok
Hydrant Flow test from City of Bozeman
Static Pressure= 102.0 psi
Flow(4.5"nozzle)= 2000.0 gpm
Residual Pressure at flow= 92.0 psi
Head Losses(at fire hydrant flow test flow rate)
hs -2.5 ft
hf= 23.8 ft
hm 1.6 ft
ht,ta= 22.9 ft
Residual Pressure from hydrant flow test= 92 psi
212.3 ft
Redisdual Pressure at End Fire Hydrant at 2000 gpm= 82.1 psi
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2 0 2 0
Shaping Our Future Together
CITY OF BOZEM
HYDRANT PRESSURE/FLOW REQUEST FORM
Date: 4/5/12
Location H drant Static Pressure Pito Pressure Residual Pressure
Commerce Way 440 13.5#
Baxter Lane 1256 102# 92#
Requested By:Ryan Ritter
Fax#emailed
Nozzle Size Flowed:4.5"
Done By: ES/JB
Comments: 2000 GPM
1178 1714
1158 1159. 11,56 __12 1161 1 i 171'.-4,4
2193 210 —_-- —
1137
1958 441 2059
2192 2191 15
2060 "
1591 1593 1957
2062