Storage Tank Brauer

7/31/2019 Storage Tank Brauer

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Wyoming Small Public WaterSystem Design and OperationSeminar

Storage Tank Design

Thomas Brauer, CEPI


2/31

Presentation Overview

Definition of Tanks

Water Storage Tank Sizing

Storage Tank Siting and Elevation Tank Design and Standards

Tank Amenities


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Types of Water Storage Tanks Tank Materials

Welded Steel

Bolted Steel

Reinforced Concrete Tank Types

Reservoirs (diameter > height)

Standpipes (diameter < height)

Elevated Multiple Column

Spherical Pedestal (Hydrosphere)

Modified Single Pedestal


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Reservoir


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Standpipe


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Mult i-Column Elevated


7/31Hydrosphere


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Elevated Bolt ed Steel


9/31Elevated Pedestal


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Design and Cost Considerations

Reservoir Standpipe Elevated

Lowest Cost

Low Visibility

Usable StorageVolume

Water Quality

Higher Cost

High Visibility

GeotechnicalConsiderations

Low Usable StorageVolume

Improve Pressures

Reduce TransmissionMain Length

Water Quality

Highest Cost

High Visibility

GeotechnicalConsiderations

Usable StorageVolume

Improve Pressures

Reduce TransmissionMain Length

Water Quality


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Water Storage Tank Sizing Criteria

Tank Inlet Tank Outlet

Emergency Storage

Equalization Storage

Fire Storage

Tank Inlet Tank Outlet

Emergency Storage


Fire Storage

DEQ Requirements

ADD < 50,000 gal/day One day ADD

ADD: 50,000 to 500,000 gal/day ADD + Fire Flow

ADD > 500,000 25% MDD + Fire Flow


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5700

5200

5500

5400

5000

5300

4900

5100

5600

LDC Field

Tank

LDC 1

El = 5400

LDC 2

El = 5440

Indian Hills Tank Sunup Ridge Tank

Figure 5- 1

Town of Glenrock

Water Supply System

Schematic & Hydraulic Profile

Glenrock Field

Tank

GW5

34,000 gal.

Base = 5401

OF = 5419

GW7

Cl2

M

Glenrock Wellfield

Well House

M

279,000 gal.

Base = 5687

OF = 5706

M

Cl2

M

LEGEND:

Flow Direction

Point of Chlorination

Water Meter

Check Valve

Pressure Reducing Valve

Water Storage Tank

Well Building

Elevation in Feet

M

M

Cl2

MM

600,000 gal.

Base = 5173.8

OF = 5216.8

977,000 gal.

Base = 5161.8

OF = 5216.8

CemeteryPRV Vault

Town of Glenrock

Transmission and Distribution System

5000

Glenrock

Wellfield

14 PVC Transmission

16DIPTransmission

Intermediate

PRV

GW Field

PRV

LDC

Wellfield

5700

5200

5500

5400

5000

5300

4900

5100

5600

5700

5200

5500

5400

5000

5300

4900

5100

5600

LDC Field

Tank

LDC 1

El = 5400

LDC 1

El = 5400

LDC 2

El = 5440

LDC 2

El = 5440

Indian Hills Tank Sunup Ridge Tank

Figure 5- 1

Town of Glenrock

Water Supply System

Schematic & Hydraulic Profile

Glenrock Field

Tank

GW5

34,000 gal.

Base = 5401

OF = 5419

GW7

Cl2

M

Glenrock Wellfield

Well House

M

279,000 gal.

Base = 5687

OF = 5706

M

Cl2

M

LEGEND:

Flow Direction

Point of Chlorination

Water Meter

Check Valve

Pressure Reducing Valve

Water Storage Tank

Well Building

Elevation in Feet

M

M

Cl2

MM

600,000 gal.

Base = 5173.8

OF = 5216.8

977,000 gal.

Base = 5161.8

OF = 5216.8

CemeteryPRV Vault

Town of Glenrock

Transmission and Distribution System

5000

Glenrock

Wellfield

14 PVC Transmission

16DIPTransmission

Intermediate

PRV

GW Field

PRV

LDC

Wellfield


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Glenrock Wellfield Supply Storage

Analysis Fire Storage None

Emergency Storage four wells with

standby power for three wells Minimal

Equalization Well cycle time, tank fillingand draining cycles


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Wellfield Equalization StorageFigure 7-9 48 Hour System Demands vs. Source Water Supply

0

200

400

600

800

1,000

1,200

1,400

12:00AM

4:00AM

8:00AM

12:00PM

4:00PM

8:00PM

12:00AM

4:00AM

8:00AM

12:00PM

4:00PM

8:00PM

12:00AM

FlowRate(gpm

System Demand (gpm)

Source Supply (gpm)

200 GPM (2-inch PRV flow)

1,250 GPM (8-inch PRV flow)


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Glenrock Distribution Storage Analysis

Emergency Storage 8 hours to repair welltransmission pipeline at MDD

Fire Flow Storage (ISO)

Residential 1500 gpm 2 hour duration Commercial 2500 gpm 3 hour duration

Equalization MDD Diurnal Curve

15 to 20% of ADD 3 hours PHD less Supply Capacity


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Calculated Diurnal Equalization Storage

Figure 7-12 Method 1 - Equalization Storage Requirements

0.50

0.60

0.70

0.80

0.90

1.00

1.10

1.20

1.30

1.40

1.501.60

12:00AM

1:00AM

2:00AM

3:00AM

4:00AM

5:00AM

6:00AM

7:00AM

8:00AM

9:00AM

10:00AM

11:00AM

12:00PM

1:00PM

2:00PM

3:00PM

4:00PM

5:00PM

6:00PM

7:00PM

8:00PM

9:00PM

10:00PM

11:00PM

12:00AM

WaterUsageFactor

Area Under Curve = 3.0 X MDD

Required Equalization Storage

Maximum Day Demand (MDD)

MDD Diurnal Curve

Figure 7-12 Method 1 - Equalization Storage Requirements

0.50

0.60

0.70

0.80

0.90

1.00

1.10

1.20

1.30

1.40

1.501.60

12:00AM

1:00AM

2:00AM

3:00AM

4:00AM

5:00AM

6:00AM

7:00AM

8:00AM

9:00AM

10:00AM

11:00AM

12:00PM

1:00PM

2:00PM

3:00PM

4:00PM

5:00PM

6:00PM

7:00PM

8:00PM

9:00PM

10:00PM

11:00PM

12:00AM

WaterUsageFactor

Area Under Curve = 3.0 X MDD

Required Equalization Storage

Maximum Day Demand (MDD)

MDD Diurnal Curve


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Year 2010 2020 2030

MDD 1,130 gpm 1,230 gpm 1,350 gpm

PHD 1,700 gpm 1,850 gpm 2,030 gpm

Emergency Storage(8 hours X MDD) 540,000 gal 590,000 gal 650,000 gal

Fire Flow Storage

(2,500 gpm for 3 hours)450,000 gal 450,000 gal 450,000 gal


Method 1 3.0hrs * MDD 203,000 gal 220,000 gal 240,000 gal

Method 2 15% MDD 240,000 gal 270,000 gal 290,000 gal

Method 3 3 hours X (PHD 1,500 gpm) 36,000 gal 63,000 gal 95,000 gal

Calculated Storage Required

(minimum and maximum)

1,030,000 to

1,230,000

gallons

1,100,000 to

1,310,000

gallons

1,200, 000 to

1,390,000

gallons

Available Storage (Total) 1,577,000 gal.

Available Storage (Operational) 1,420,000 gal.

DEQ Equalization Storage

(25% of MDD)407,000 gal 443,000 gal 486,000 gal

DEQ Fire Storage

(2,500 gpm for 3 hours)450,000 gal 450,000 gal 450,000 gal

Calculated DEQ Storage Required 857,000 gal 893,000 gal 936,000 gal


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Usable Storage vs. Available Storage

Available Storage = Total Volume of Tanks

Usable Storage = Volume Available toMaintain 35 psi @ PHD and 20 psi @ MDD

w/ Fire Flow Reservoir Usable Storage

Standpipe Usable Storage

Elevated Tank Usable Storage Develop System and Demand Curves


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Tank Sizing Design Considerations

Dont be too Conservative! Realistic Assumptions Water Quality

Sizing Considerations Assume: Supply and Transmission Capacity = MDD No standby power Three components additive Adjust your analysis accordingly

Tank Cycling Water Quality System Operational Pressures System Curves


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Tank Siting and Elevation System Operational Pressures

35 psi normal; 20 psi MDD with Fire Flow

System Curves

Tank Cycling (ice and water quality)

Higher is better!

Geotechnical Considerations Collapsible Soils

Swell and Consolidation Analysis

Tank Drain and Overflow Piping

Slope Failure

Transmission Supply Proximity to Distribution

Transmission Storage

Water Quality


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Tank Design Standards

DEQ Chapter 12

AWWA D-100 (D-100-11 forthcoming)

API Standards Reference Standards and Specify Tank

Performance Specification vs. Structurally

Designed Solution Provide Technical Specifications and Tank

Elevations and Detail Drawings


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Design Considerations - Tank Foundation

Reinforced Concrete Ringwall Inlet and Outlet Piping

Concrete Boxes Welded Steel Piping

Separate Inlet and Outlet Piping Separate Drain Line Silt Rings

Structural Fill and Drainage Rock

Floor Slope and Drain Floor Sheet Cathodic Protection

Anodes Oil Soaked Sand


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Design Considerations Steel Tank Roof Type

Knuckled Roof Self Supporting Dome Sloped Roof

Overflow Piping Internal vs. External Overflow

Structural Members Columns Rafters

Vents Screening Sizing

Wind and Seismic Design


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Design Considerations Amenities

Ladder Safety Cage

Platforms

Safety Climb RailAccess Hatches

Roof (directly over overflow pipe)

Shell (minimum of two, maximize size) Internal

External


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Design Considerations - Ice

Ice Formation (walls and roof) Free Board

Ladders

Overflow Piping Internal

External

Weir Box

Structural Stiffeners

Tank Vents

Cathodic Protection Systems

Tank Cycling and Mixing


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Red Valve Tideflex Check Valves

and Tank Mixing Tank Water Quality Issues

Chlorine Residual

Bacteriological Growth Multiport Tank Mixing Systems

No power requirements

Constant Velocity Orifice Valve Tank Cycling is Still Important

Check Valves (inlet, overflow and drain)

Mike Duer, P.E.Red Valve Company, Inc.

Tideflex Technologies Division600 North Bell AvenueCarnegie, PA 15106

Tel: (412) 279-0044 x233


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Design Considerations - Tank

Coating Bolted Steel Tanks Glass Lined Tanks

Limited Number of Suppliers

Surface Preparation

Atmospheric Conditions Coating System

Three Coat w/ Stripe Coat

Structural Design Limitations(columns, rafters, painters rail)

Construction Monitoring and QA/QC Testing andReporting

Environmental Testing and Safety


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Reference Material

AWWA M42 Steel Water Storage Tanks AWWA M32 Distributions Network Analysis for Water

Utilities

DEQ Chapter 12

AWWA D100 Welded Steel Tanks AWWA D102 Coating Steel Water Storage Tanks

AWWA C652 Disinfection of Water Storage Facilities

AWWA D103 Factory Coated Bolted Steel Tanks

AWWA D104 Automatically Controlled Impressed-CurrentCathodic Protection Systems

API Standards

Documents

Storage Tank Brauer