progress report #1 for the heyburn, idaho municipal water ... · the project site is in heyburn,...
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Progress Report #1 for the Heyburn, Idaho Municipal Water Supply Expansion
Reporting Period: January 26 – February 28, 200-
Submitted by
ADAGE ENGINEERING
Jim Smith Bill Jones
Mary Reed Justin Blue
Neal Oldhome Wallace Lake
to Civil Engineering Faculty
Boise State University 28 Feb 200-
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Table of Contents Page
A. Executive Summary...............................................................................................3
B. Introduction.............................................................................................................5
C. Progress of Work....................................................................................................8
1. Geotechnical Analysis......................................................................................8
2. System Component Design............................................................................10
a. Storage Tank Design..................................................................................10
b. Disinfection System Design........................................................................12
c. Pump Selection...........................................................................................13
d. Pump House Design...................................................................................13
e. Drainage Pond Design................................................................................13
3. Site Development.............................................................................................14
a. General Site Layout.....................................................................................14
b. Access Road and Parking Lot Design.........................................................15
D. Overall Assessment of the Project........................................................................15
E. Acknowledgements..............................................................................................16
F. References...........................................................................................................17
Appendix A: Memo: DEQ Guidelines and Checklists...................................................18
Appendix B: Boring 1 Liquefaction Analysis.................................................................21
Appendix C: Boring 2 Liquefaction Analysis.................................................................25
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A. Executive Summary
Adage Engineers is designing an expansion of the Heyburn, Idaho municipal water
supply system. This includes design of a water tank, pump station and necessary
support components on a 1.17 acre lot adjacent to Lincoln Boulevard in Heyburn that is
approximately 500 feet from the Snake River. We have added a drainage pond to the
design that was not included in the original proposal. This report presents the progress
made from January 26 to February 28, 200-. No problems have been encountered, and
the project is on schedule.
The design for the water storage tank is based on a maximum daily average flow of 750
gallons per min (gpm), a maximum peak hour flow of 1,500 gpm, and a two-hour fire
flow of 1,500 gpm. The nominal size of the tank based on the first of these flows is one
million gallons (1MG). Consideration of the other flows required additional storage.
Water will be supplied by a ground water well on the property that yields 1,000 gpm.
Tasks and progress to date include the following:
A. Tank Design - We have determined that the total volume needed for the storage
tank is 1.4MG. We are in the process of selecting the tank materials and design.
B. Geotechnical Analysis – Based on data from two borings and a test pit, we have
calculated a bearing capacity of 3,500 pounds per square foot (psf) and we have
determined that the potential for liquefaction of subsurface soils is very low. We
are proceeding with tank foundation and access road designs.
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C. System Component Design – We will be specifying the number and type of
pumps required, the disinfection system, and designing the three-room pump
house in the coming weeks.
D. Site Development – A preliminary site plan was developed in which the tank is
located near the center of the lot where the land is fairly level, the pump house
and parking lot are together near the high end of the property close to Lincoln
Boulevard, and the drainage pond is at the low end of the property.
The tasks we intend to complete before the next progress report include:
• Identification of all necessary permits (Appendix A)
• Finalization of site plan
• Tank design and materials
• Disinfection system design
• Pumping system design and selection of pumps
• Standby generator selection
All the design work will meet applicable local, state, and federal requirements.
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B. Introduction
This report details the progress made from January 26 to February 28, 200-, on the
project to expand the municipal water supply system for the city of Heyburn, Idaho. The
municipal water demand in Heyburn is growing and cannot be met by the existing
supply. The new water supply tank provided by the present design is expected to
satisfactorily augment the existing water system through 2025. The water will be
supplied by an existing well which has been shown to yield a constant flow of at least
1000 gpm (cite reference here).
The project scope is to develop necessary plans, profiles, and designs to:
• Construct a water supply tank with an operating capacity of 1.4 MG,
• Construct a building to house pumps, a standby generator, and chlorination
equipment
• Provide connection to the existing water system
• Provide roadways for access and fencing for access control and safety
The project site is in Heyburn, shown on the state map in Figure 1a, and is near 7th
Street in Heyburn (Figure 1b). The site is a rectangular plot measuring 210 ft by 243 ft (
1.17 acres). Water supply requirements, as specified by the city, are to meet an average
daily demand of 750 gpm, a maximum peak hour demand of 1,500 gpm, and a two-hour
fire flow of 1,500 gpm.
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Figure 1. a) Project location, and b) Aerial photograph of site (cite references)
The project work includes the following tasks:
1. Permitting
2. Geotechnical Analysis
3. System Component Design
a. Storage Tank
b. Disinfection System
a) b)
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c. Pumping System and Connection to Existing Distribution System
d. Pump House and Standby Power Generator
e. Drainage Pond
4. Site Development
a. General Site Layout
b. Access Road and Parking Lot Design
We are using IDAPA 58.01.08 (DEQ,2000a) and “Checklists for Plan and Specification
Review for Engineers and Developers” (DEQ, 2000b) as guides for the design.
As of Feb. x, 200x, we have determined the required water tank storage volume,
completed the geotechnical analysis necessary for design of the tank foundation and the
roadways, and developed a preliminary site layout. We anticipate completing water tank
design, pump sizing, connection piping design, generator selection, and chlorination
system design by March 18 and building, road, and drainage pond plans by April 22.
Work on the project is due to be completed and a final report submitted by May 1, 200-.
C. Progress to date
1. Geotechnical Analysis Figure 2 shows the location of the two boreholes and a test pit that provided the
geotechnical data for the site. These data were used to estimate the bearing capacity
and liquefaction potential of the soil. The bearing capacity was calculated using
Terzaghi’s bearing capacity equations for a square footing (Das, 2006):
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qu = 1.3c’N’c + qN’q + 0.4γBN’γ (1)
and
qall = qu / FS (2)
where qu = the ultimate bearing capacity in pounds per square foot (psf),
qall = the gross allowable bearing capacity in psf,
c’ = cohesion coefficient [assumed = 0 for sands (Das, 2006)],
ɸ’ = angle of friction for loose sand [assumed = 30 degrees (Das, 2006)],
N’c , N’q , and N’γ = modified bearing capacity factors from Das (2006) for loose sand with ɸ’ = 30 degrees, gave values, respectively, 37.16, 22.46, and 19.13,
B = length of footing in ft [assumed = 3 ft],
γ = unit weight of soil in pounds per cubic foot (pcf) [assumed = 120 pcf],
q = surcharge in psf [Bγ = 360], and
FS = factor of safety, [assumed = 3].
Eq. 1 and 2 yielded a bearing capacity of 3613 psf, which was used to design the
tank foundation.
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Figure 2. Boring and Test Pit Locations (Google, 2008).
Liquefaction potential of the site was investigated. Boring 1 showed a layer of elastic silt
from 21 feet to 27 feet below ground surface (bgs) and Boring 2 showed a layer of fat
clay from 20.5 feet to 26 feet bgs. These layers have the potential to cause liquefaction
where the fat clay/elastic silt layer comes in contact with an overlying sand layer so we
performed a liquefaction analysis with a software program called LiqIT (GeoLogismiki,
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2006).The program used soil data and other factors to calculate the Owasaki
Liquefaction Potential Index (LPI) for the soils from the two borings at the site. The LPI
values obtained at both sites were zero, indicating that the probability of liquefaction and
resulting settling due to liquefaction is very low. The results of the analysis are shown
in Appendices B and C.
2. System Component Design
a. Storage Tank Design
The first step in the storage tank design was to calculate the actual volume of the tank.
The nominal operating volume provided as a design requirement was 1MG, but other
factors that must be considered added volume to the requirement. We used IDAPA
58.01.08 Section 003.12 and Section 501.03 (DEQ, 2000a) as a guide in calculating
these additional volumes according to flow quantities specified by the city of Heyburn for
the design (e.g., 750 gpm for the maximum daily average, 1,500 gpm for the maximum
peak hour, and 1,500 gpm for two hours of fire flow).
Each component of total required volume for the tank is indicated and estimated below.
• Operational: One day of maximum daily average flow [750 gpm x 24 hrs = 1.08
MG].
• Equalization: Make-up storage between flows at maximum peak hourly rate and
well supply rate during estimated time of maximum peak hourly flow [(1,500 –
1,000) gpm for 2 hours = 0.06 MG]. This is exclusive of fire flow.
• Fire Suppression: Storage for fire flow [1,500 gpm for 2 hours = 0.18 MG].
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• Dead Volume - Water that, for whatever reason, may not be usable. For
example, this would be water located in the tank below an outflow pipe. We
intend to design the tank with no dead volume, so we used a value of zero
gallons for dead volume.
• Standby: Storage usually recommended to round the tank volume up to the
nearest 100,000 gal. [1.08 + 0.06 + 0.18 = 1.32 MG; Standby = 0.08 MG]
The total volume of the tank according to these estimates was calculated to be 1.4 MG.
The turnover time of 31 hours for the tank was calculated by dividing the volume of the
tank by the maximum daily average flow rate. This is a criterion used in design to make
sure the tank is not oversized. If the turnover time is too long, one risks stagnation
problems in the water; if it is too short, one risks running out of water quickly if supply is
interrupted. The value of 31 hours is within the range recommended by DEQ (2000a).
The next step in the tank design is to select the shape, either cylindrical or rectangular
and material of construction, reinforced concrete or steel. Our research so far favors
constructing a rectangular tank of reinforced concrete construction. We intend to have
our choice made and the design completed by the date of the next progress report.
b. Disinfection System Design
The ground water used to supply the storage tank will likely need no treatment beyond
what is required by typical disinfection with chlorine. Additional water treatment to meet
public water supply requirements, if needed, is beyond the scope of this project.
We are considering the following aspects in the design of the disinfection system:
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• Type of disinfectant to be used
• Source of the disinfectant
• Public safety
• Means to introduce the disinfectant into the water supply
• Mixing and detention time
• Residual concentration
Our preference at this time is to use chlorination with chlorine gas generated on site.
This is a common system used in many other locations to provide residual disinfection
throughout distribution systems (cite reference). This approach minimizes safety
problems associated with locating large tanks of chlorine gas on site. With on-site
generation, the chlorine gas is injected into the supply line coming from well and is
mixed by the turbulence in the pipe. The large volume of the storage tank provides the
required detention time after mixing before the water is pumped out to the distribution
lines. Baffling or other means needed to prevent short circuiting and guarantee
adequate detention times will be addressed in our design of the tank. Since the water
from the new tank will tie into the existing water supply system, we must design to match
the chlorine residual concentration at the tie-in point. The design will follow IDAPA
58.01.08 section 541.04 (DEQ, 2000a).
c. Pump Selection
The city of Heyburn requires an average pressure of 40 pounds per square inch (psi),
and a maximum of 70 psi in the water distribution system. We will provide a design of
multiple pumps that meet these pressures while pumping up to 750 gpm for normal flow,
1,500 gpm for maximum flow, and 3,000 gpm for maximum flow plus fire flow. We
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believe that three identical variable frequency drive water booster pumps of adequate
capacity would provide the benefits of economical operation, maintenance, and
replacement.
d. Pump House Design
The pump house will consist of three rooms: pump room, generator room, and
chlorination room. Selection of materials for the pump house will be based on cost and
availability. Alternative materials for walls include concrete masonry units (CMUs),
precast concrete, wood, or poured in place concrete. We are considering wood or steel
trusses for the roof. A window and an access door will be included between the main
pump room and the chlorination room for monitoring purposes. We will follow IDAPA
58.01.08 section 541.01 (DEQ, 2000a) to guide our design.
e. Drainage Pond Design
Our initial proposed design did not include a drainage pond. Such a pond is necessary
to provide catchment for tank overflow and for storage when the tank must be drained.
The pond must be there to contain water from the site and prevent any contamination of
the ground water or the nearby Snake River. We will design the pond to provide fail-
safe control.
a. General Site Layout
Figure 3 shows our preliminary site layout. The lot is 210 ft by 243 ft and slopes
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Figure 3. Initial Site Layout [Topo map from Sunrise (2000)]
approximately ten feet from the northeast corner to the southwest corner. The middle of
the lot is relatively flat.
We propose to locate the water tank in the center where there will be a minimal grading
required. The pump house is near an easy access point and is on relatively flat ground.
The pond is on the lowest area of the property. The slope of the lot would allow for
gravity flow from the tank to the pond. .
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b. Access Road and Parking Lot Design
An access road will connect the site to adjoining Lincoln Boulevard and a 3,200 ft2
parking lot will be provided (Figure 3). The design of the access road will follow the
Idaho Transportations Department (ITD) standards (ITD, 2005). Our plan is for a 16-ft
wide access gate and for the property to be protected on all sides with a 6-ft high chain
link fence topped by barbed wire. Gravel will be used for the parking lot and for a 15 ft
wide access road around the perimeter of the water tank in accordance with applicable
standards.
D. Summary
The project is on schedule. The water tank volume has been finalized and design of the
tank is underway. We have analyzed the geotechnical data and determined the bearing
capacity of the soil and evaluated the potential of liquefaction at the site. We are
proceeding with design of the tank foundation. We have done preliminary work on the
pump house design, pump selection, and the disinfection system. We have added a
pond for tank overflow and/or drainage and we will design it. A preliminary site plan has
been drawn with placement of the tank, the pump house, a parking area, access roads,
an access gate, and fencing. We have encountered no major problems in meeting our
schedule.
E. Acknowledgements
We would like to thank Sunrise Engineers and Strata, Inc. for providing us maps and
needed data concerning the project. Thanks to Keller Associates for giving input on
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storage tank design and to Materials Testing & Inspection for allowing us to use
software and resources for the geotechnical analysis.
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F. References Das, B.M (2006). Principals of Geotechnical Engineering, Sixth Edition, Thomson,
Toronto, Canada, 686 pgs.
Google (2008). “Google Maps,” Internet: http://maps.google.com/. Accessed 2/27/08.
Idaho Department of Environmental Quality (DEQ) (2000a). “Checklists for Plan and
Specification Review for Engineers and Developers,” Internet:
http://www.deq.idaho.gov/water/assist_business/engineers/checklists.cfm.
Accessed 2/20/08.
Idaho Department of Environmental Quality (DEQ) (2000b). “IDAPA 58.01.08 – Idaho
Rules for Public Drinking Water Systems,” Boise, ID, 114 pgs.
Idaho Transportation Department (ITD). (2005) “Road Design Policy Manual”. Boise,
ID, 643 pgs.
Sunrise Engineering, 2008, Water Tank Topo.dwg.
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Appendix A: Memo: DEQ Guidelines and Checklists
INTEROFFICE MEMORANDUM
TO: LE Planner and Designers
FROM: Wes Rood
SUBJECT: Propose a Change in Scope of Work for City of Heyburn
DATE: 2/14/2009
CC: Municipal Group
Hey Guys,
I met with Dr. Miller last Friday 2/15/08 at 2:30 pm to discuss the permits needed for
our project. When discussing with her I soon discovered we are not using the proper
design guidelines needed for our project. I started to see the purpose of the CE480
senior design class. The purpose of the class is to teach us how to put a project together
using state and federal rules and regulations. If we do not follow these rules our project
will never get hypothetically funded or built. Yes, it is true there is a hundred different
ways to design anything and make it work but, there is only one way to get our project
approved by the state and federal agencies. We need to use the design check lists
supplied by our state and federal agencies.
The CE480 class does not require us to have a complete set of drawings for our
municipal water project, though the class does require that we follow the correct
procedure for designing a project. I believe if we followed these rules and regulations we
will be able to perform any job or know were to start a job when we enter the work force,
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actually we will be ahead of the game because so many engineers never follow these
guidelines and end up fighting the system.
The following links will show you the guidelines that we need to follow:
http://adm.idaho.gov/adminrules/rules/idapa58/0108.pdf
Page 35 in this document is very critical we need to explain that we covered all these
requirements in our progress reports. In the final report say we need have a qualified
operator to run the new municipal system.
http://www.deq.idaho.gov/water/assist_business/engineers/checklists.cfm
This site has the engineer’s permits and check lists. Twin falls Idaho DEQ is the
regulating agency which is monitoring the City of Heyburn not the DEQ in Boise.
When we submit our final report we need to include the following: In the future before
we would start designing, we would have preliminary design drawings that we would use
to show the state and federal agencies and ask them what they will require in order for
the project to pass state and federal rules and regulations (i.e. codes). We will also need
to include these rules in our appendix (checklists and permits). We will also need to
include a TFM report this is a report explaining how the new system will effect or modify
the existing water system.
Dr. Miller has offered to sit down with us and go over the proper method of
submitting a project to state and federal agencies. She will be available on Thursday the
2/21/08 or Friday 2/22/08 we just need to set up a meeting with her. I would recommend
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this because I learned a lot from the meeting I had with her on Friday the 2/15/08. I
know this will set us back in our design but I do believe that this is very important.
Note: She said we are not allowed to move test bore pits around to suit our water
system site because this would be falsifying information. Though we can use the worst
case on the site and assume the characteristics across the site.
Bill: The correct size of the booster pump building is 30’x36’ sorry I did not get this to
you sooner. I think the site looks good we just need to check it against the codes.
Mo: I left a message on Dr. Millers white board explaining that I would be there at her
office at 10:40am because I for got I had class until 10:30am. Sorry!
Let me know your opinion. I think we need to have a meeting tomorrow 2/19/08 to
discuss this issue.
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Appendix B: Boring 1 Liquefaction Analysis
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Appendix C: Boring 2 Liquefaction Analysis
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