MINIMIZE YOUR FOOTPRINT AND YOUR MAINTENANCE HEADACHES

SELF CLEANING TRENCH TYPEWET WELL DESIGNS

T W S ith P ETrooper W. Smith, P.E.Mukesh R. Pratap, P.E.Freese and Nichols, Inc.

1701 North Market Street, Suite 500 LB51Dallas TX 75202

AGENDA

1 Presentation Objectives1. Presentation Objectives

2. Project Background

3. Pump Station Evaluation

4. Trench Type Wet Well

5 C t ti U d t5. Construction Updates

6. Acknowledgements / Questionsg Q

PRESENTATION OBJECTIVES

Introduction to Trench Type Wet Wellsyp

Introduction to Self Cleaning OperationIntroduction to Self Cleaning Operation

Why Factor ?

TOPIC

1 Presentation Objectives1. Presentation Objectives

2. Project Background

3. Pump Station Evaluation

4. Trench Type Wet Well

5 C t ti U d t5. Construction Updates

6. Acknowledgements / Questionsg Q

PROJECT SCOPE

Trinity River Authority

Trinity River AuthorityCRWS Treatment Plant

Design and Construction of Pump Station 13B

Fl id f I t t R t A ti t d Sl dFluid of Interest: Return Activated SludgeFinal Clarifiers – Traveling Bridge Suction Clarifiers

Firm Capacity - 50MGDPS-13 – 50 MGD (North Plant, Trains 1-3)PS 13B 50 MGD (North Plant Trains 4 6)PS-13B – 50 MGD (North Plant, Trains 4-6)PS-13A – 100MGD (South Plant, Trains 7-12)

13

13B13B

13A

HISTORY OF THE PROJECT

YEAR 2005 YEAR 2007YEAR 2007

YEAR 2006YEAR 2007

to 2009

FEASIBILITY REPORT

PRELIMINARY DESIGN FINAL

DESIGNCONSTRUCTION

PHASEREPORT REPORT DESIGN PHASE

TOPIC

1 Presentation Objectives1. Presentation Objectives

2. Project Background

3. Pump Station Evaluation

4. Trench Type Wet Well

5 C t ti U d t5. Construction Updates

6. Acknowledgements / Questionsg Q

PUMP STATION EVALUATION

Dry Pit/Wet PitDry-Pit/Wet-PitHorizontal Non-Clog Centrifugal Pumps (PS 13 and PS 13A)(PS-13 and PS-13A)

Vertical Non-Clog Centrifugal Pumps (PS 6 d 6A)(PS-6 and 6A)

Wet PitWet-PitVertical Turbine Solids Handling Pumps (VTSH)

Pump Station 13A – Horizontal Non-Clog Centrifugal Pumps (Wet Pit/Dry Pit)

Pump Station 6 – Vertical Non-Clog Centrifugal Pumps (Wet Pit/Dry Pit)

Pump Station 6A – Vertical Non-Clog Centrifugal Pumps (Wet Pit/Dry Pit)

Pump Station 13A Horizontal Non-Clog Centrifugal Pump(PS-13A)

Vertical Non-Clog Centrifugal Pumps(PS-6 and 6A)

VTSH PUMPS

VTSH PUMPS

City of Phoenix, 23rd Ave. WWTP(36-inch VTSH Pumps)

LIMITATIONS AT PS-13B SITE

60-inch Final Clarifier Effluent line

84-inch Primary Clarifier Effluent line

Electrical Duct Bank

Caustic Soda Tank

2-inch to 12-inch Lines

12-foot Roadway

Existing Structures and Utilities

DRY PIT VERSUS WET PITR l t d 60 i h FCE Li

Relocated PavementRelocated 60-inch FCE Line

Footprint of Dry-Pit/Wet-Pit(Horizontal Non-Clog Pumps)

Relocated Caustic Soda Building

( o o No C og u ps)

Relocated 84-inch PCE Line

Footprint of Wet-Pit Wetwell(VTSH Pumps)

Existing Caustic Soda Storage Facility, 84-inch PCE Line, 60-inch FCE Line and Pavement Remains Unchanged

DRY PIT VERSUS WET PIT

Pump Station Type

Length/Width Depth Pump Cost ($)*

OPCC ($)**

Horizontal Non-Clog Centrifugal Pump

67’/65’ 26’ $915,000 $10.9 millionCentrifugal Pump Station (Wet Pit/Dry Pit)

Vertical Non-Clog Centrifugal Pump Station (Wet Pit/Dry Pit)

59’/54’ ~ 35’ $945,000 $11.4 million

Station (Wet Pit/Dry Pit)

VTSH Pump Station (Wet Pit)

49’/43’ 29’ $1,718,000 $9.5 million

* Total Pump Cost for 3 Pumps* Total Pump Cost for 3 Pumps** OPCC: Opinion of Probable Construction Cost

TOPIC

1 Presentation Objectives1. Presentation Objectives

2. Project Background

3. Pump Station Evaluation

4. Trench Type Wet Well

5 C t ti U d t5. Construction Updates

6. Acknowledgements / Questionsg Q

TRENCH TYPE WETWELL

i bl f iSuitable for Design Flows > 3 MGD

Pump Intakes, Confined in a Deep, Narrow Trench

Pump Intakes, Substantially Lower Than Upstream Inlet Pipe

Suitable for Different Pump Types/Arrangementsyp g

TRENCH TYPE WET WELL

AdvantagesHydraulic Environment for Pump IntakesMinimum Footprint SizeSmall Floor Area (Minimum accumulation of sludge or grit)

Ease and Quickness of Cleaning

DisadvantagesC t Mi i l St C itCompact, Minimal Storage CapacityIncreased DepthClogging if Pumps Not UsedClogging if Pumps Not Used

TRENCH TYPE WETWELL

Invented by D.H. Caldwell (1964)

1998 Breakthrough1998 Breakthrough2nd Edition of Pumping Station DesignANSI/HI 9.8 Pump Intake Designp g

TRENCH TYPE WETWELL

Illustrative View of Kirkland Pump Station (Washington)

IMPROVED TRENCH DESIGN

Dr. Robert Sanks, Ph.D., P.E.

1:1 scale model of portion of a trench floortrench floor

Result: >5fps requirement

1 3 3 l d l f th1:3.3 scale model of the Kirkland Pump Station

Result: Only a small portion of the sand was ejected at pump down until equilibrium

ANSI/HI 9.8 Pump Intake Design (1998)

ANSI/HI 9.8 Pump Intake Design (To Be Released)

WET PIT VERSUS TRENCH TYPE

Pump Station Type

Length/Width Depth(Feet)

Pump Cost ($)*

OPCC ($)**

Wet Pit Pump Station 49’/43’ 30’ $1,718,000 $9.5 MillionWet Pit Pump Station 49 /43 30 $1,718,000 $9.5 Million

Trench Type Wet WellPump Station

57’/18’ 38’ $1,718,000 $8.5 Million

* Total Pump Cost for 3 Pumps** OPCC: Opinion of Probable Construction Cost

Site Plan – RAS Pump Station 13B

W t ll T h Fl S littWetwell Trench Flow Splitter

Wet Well Plan Elevation at 415.00’

SECTION VIEWS

SlopingWalls

Water Guide

W s

FilletFlow

Splitter Trench

SECTION VIEWS

4 fps (wet pit)3 fps (dry pit)

1 fps maxabove 3 fps (dry pit)trench

Illustrative Section of Pump Station 13B – Normal Operation

SELF CLEANING CYCLE

CleaningRamp 30-60%

Flow

TrenchComponents

Trench

PumppDown

HydraulicJumpp

Mixes sludge and scum into a massthat is ejected by the last pump

Cleaning Rampg p

Illustrative Section of Pump Station 13B – Cleaning Cycle (Pump Down)

Cleaning Rampg p

Illustrative Section of Pump Station 13B – Cleaning Cycle (Pump Down)

Cleaning Rampg p

Illustrative Section of Pump Station 13B – Cleaning Cycle (Pump Down)

Cleaning Rampg p

Illustrative Section of Pump Station 13B – Cleaning Cycle (Pump Down)

PUMP STATION 13B TESTING

Scenario 1

Scenario 2A

Scenario 2B

•1 clarifier •2-3 clarifiers •2-3 clarifiers

•16MGD

•Sluice gate for proper flow

•32-50MGD

•2 pumps at full speed let

•32-50MGD

•Sluice gate for proper flowfor proper flow

rate

•Use last pump

full speed, let turbulence do the cleaning

for proper flow rate

•Use last pump

TOPIC

1 Presentation Objectives1. Presentation Objectives

2. Project Background

3. Pump Station Evaluation

4. Trench Type Wet Well

5 C t ti U d t5. Construction Updates

6. Acknowledgements / Questionsg Q

CONSTRUCTION UPDATEOctober 1, 2007

CONSTRUCTION UPDATEOctober 19, 2007

CONSTRUCTION UPDATENovember 14, 2007

CONSTRUCTION UPDATEJanuary 18, 2008

CONSTRUCTION UPDATEFebruary 13, 2008

CONSTRUCTION UPDATEFebruary 28, 2008

CONSTRUCTION UPDATEMarch 12, 2008

CONSTRUCTION UPDATEMarch 20, 2008

TOPIC

1 Presentation Objectives1. Presentation Objectives

2. Project Background

3. Pump Station Evaluation

4. Trench Type Wet Well

5 C t ti U d t5. Construction Updates

6. Acknowledgements / Questionsg Q

ACKNOWLEDGEMENTS

Trinity River Authority of Texas

ANSI/HI (Hydraulic Institute) Pump Standards, 1998

Pumping Station Design, 3rd EditionEditor-in-Chief: Garr M. Jones, P.E.Co-Editors: Dr Robert L Sanks Ph D P ECo-Editors: Dr. Robert L. Sanks, Ph.D., P.E.

Dr. George Tchobanoglouos, Ph.D., P.E.Bayand E. Bosserman II, P.E.

Dr. Robert L. Sanks, Ph.D., P.E. (Quality Control)

Dr Joel E Cahoon Ph D P E Montana State UniversityDr. Joel E. Cahoon, Ph.D., P.E., Montana State University

QUESTIONSQ

Contact InformationTrooper Smith, tws@freese.com, 214-217-2219

Mukesh Pratap, mrp@freese.com, 214-217-2208