American Society of Farm Managers & Rural Appraisers Kevin Morrison, P.G. Project Coordinator – Desalination Engineering Brackish Groundwater Desalination.

American Society of Farm Managers & Rural Appraisers

Kevin Morrison, P.G.Project Coordinator – Desalination Engineering

Brackish Groundwater Desalination Program Update

October 2, 2014

October 2, 2014

Brackish Groundwater Desalination Program UpdatePage 2

Outline• Background

• Treatment Process

• Program Progress

• Program Cost

October 2, 2014


Background

October 2, 2014


SAWS Water Supply - 2014No Cutbacks

October 2, 2014


What is Brackish Groundwater?• Brackish groundwater

contains total dissolved solids (TDS) greater than 1,000 milligrams per liter – Fresh: 0 – 1,000 mg/l– Edwards: 350 – 400 mg/l – Brackish: 1,000 – 10,000

mg/l– Saline: greater than 10,000

mg/l– Seawater: greater than

35,000 mg/l

October 2, 2014


Why Brackish Desalination?

• Untapped resource

• Large volumes of available brackish water– Estimated over 2.7 billion

acre-feet

• Resource close to San Antonio

October 2, 2014


Feasibility - 2006

October 2, 2014


Carrizo – Wilcox Cross Section

October 2, 2014


Production WellsInitial Test

WellsProduction Wells

(8)Depth 1250 - 2660 1205 - 1770

Production Rate (gpm) 800-1000 800 -1100

Total Dissolved Solids (mg/L)

1437 1346

Iron (mg/L) 0.233 0.314Silica (mg/L) 18.8 18.5

Water Chemistry

October 2, 2014


Membrane Pilot Testing

• Receive TCEQ capacity rating and permit

• Test membranes from three manufacturers

• Test pre-treatment/post treatment options– “Open System” vs. “Closed System”

• Additional Investigations– Concentrate Pipe Loop Study

– Air Leak Testing

– System fouling trend and membrane autopsy SAWS Membrane Pilot Test Unit

Pilot Testing Goals

October 2, 2014


Current BGD Program • Phase I (2016)

o 12 MGD or 13,440 Acre-feet/yr

• Phase II (2021)o 12 MGD or 13,440

Acre-feet/yr

• Phase III (2026)o 6 MGD or 6,720 Acre-

feet/yr

• Totalo 30 MGD or 33,600

Acre feet/yr

October 2, 2014


Treatment Process

October 2, 2014


Diagram by Osmonics, Inc.

Reverse Osmosis Membrane Construction

RO Treatment

October 2, 2014


RO Treatment

Acid

CF

AS

Calcite Contactor,Degasification,Sodium hydroxide

Product

WellConcentrate Disposal

Raw Water Blending

RO

Concentrate

Pre-treatment

Primary treatment

Post treatment

AS: Anti-scalent CF: Cartridge Filter

13

.11

MG

D2

MG

D

10 MGD

1.1

1 M

GD

11

.11

MG

D

12 MGD

October 2, 2014


What is Concentrate/Brine• Reverse osmosis treatment plant produces

two products– 90% permeate (30-60 mg/L TDS)– 10% concentrate (~15,000 mg/L TDS)

• Concentrate stream requires disposal

October 2, 2014


Concentrate DisposalOptions Considered

October 2, 2014


Class I Test Injection WellPerforated Versus Open Hole Completion

October 2, 2014


Injection Zone

~ 860 ft. Thick

Confining Zone

~ 2,360 ft.Thick

Production Zone ~ 600 ft.

Thick

GeorgetownEdwards &

Upper Glen RoseLimestone

Midway Shale

AnacachoLimestone

Navarro Clay

Wilcox Sand(Brackish Water)

Upper Wilcox Clay

Carrizo Sand(Fresh Water)

Austin Chalk

Eagle Ford Shale, Buda

Limestone, & Del Rio Clay

Well Construction

Injection Tubing

Retrievable Packer

October 2, 2014


Class I Test Injection Well

• Total Project Cost: $4.83M• Cost Per Linear Foot: $958

Project Costs

October 2, 2014


Class I Test Injection WellInjection Well Results• Depth: 5,000 – 5,300 ft

• Injection Zone Edwards Limestone Upper Glen Rose Limestone

• Native Edwards water salinity ~ 90,000 mg/L TDS

• 450 gpm Injection Rate

• Two Injection Wells required for BGD Phase I (about 1.1 MGD)

October 2, 2014


Program Progress

October 2, 2014


20132012

Conceptual Design

Pre-Construction

Design

2015 20162014

Program Completion October

2016

Construction Management Services

Construction

Commi-ssion

Commi-ssion Warranty

Warranty

2017 2018Program Manager

(PM)

Construction Manager at Risk

(CMAR)

GMP Board AwardMarch 2014

CMAR Process• Process allows:

– Contractor’s input in the design– Engineer’s involvement in construction planning– Qualification based selection– Guaranteed maximum price (GMP)– Pursue SAWS SMWB goals

October 2, 2014


Program Components• 12 - Production Wells

• 2 – Injection Wells

• Reverse Osmosis Treatment Plant

• Pipelines

• SCADA and Electrical system

• Security

October 2, 2014


Activities Completed• Design Completed

– Wells– Conveyance– RO Treatment Plant– Electrical / SCADA– Security

• Construction and Guaranteed Maximum Price approved by SAWS Board in March

• Construction Manager at Risk in the procurement phase

October 2, 2014


Current ActivityTreatment Plant Earthwork – Jun. 21, 2014

October 2, 2014


Current ActivityTreatment Plant Earthwork – Sept. 9, 2014

October 2, 2014


Program Cost

October 2, 2014


Cost

• Total estimated construction cost:

$192.66 million

• $/AF: $1,177 / AF

• Construction in Progress

• Completion - October 2016

Phase I

October 2, 2014


Questions?

American Society of Farm Managers & Rural Appraisers

Kevin Morrison, P.G.Project Coordinator – Desalination Engineering

Brackish Groundwater Desalination Program Update

October 2, 2014

American Society of Farm Managers & Rural Appraisers Kevin Morrison, P.G. Project Coordinator – Desalination Engineering Brackish Groundwater Desalination.

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