U.S. Department of the InteriorBureau of Reclamation

A profile of the in-house and

partnered research conducted on

brackish groundwater and

Colorado River water at the Bureau

of Reclamation's Water Quality

Improvement Center, for the year

beginning October 1, 2007.

Water Quality Improvement Center

Advanced WaterTreatment Research2008

Drought Has Affected Western WaterSupplies

Water Research Identifies New Waysto Increase Water Availability

More than 20 million people in Arizona, California,Nevada, and Northern Mexico depend on ColoradoRiver water delivered by the Bureau of Reclamationthrough publically-funded dams and distributionsystems. Water delivered grows our nation's crops,supplies our cities and rural communities, servesour industries, provides recreational opportunities,and sustains plants and animals.

For the last six-to-nine years, the Colorado Riverbasin has suffered a drought that affects both waterquantity and water quality. Some states (Nevada,Colorado) have already imposed mandatory waterconservation measures; others (Arizona, California)are considering them.

No one can predict when the drought will end, buteven when it does, water supply and quality issueswill still remain.

Water quality is key to water availability - if a wateris naturally low-quality (high in minerals, forexample) or has been impaired by industrial ormunicipal use (for example, sewage effluent orplant wastewater), it would be re-usable for potablepurposes if extensively treated. The “recycled”water would increase the overall supply availablefor drinking, bathing, etc. However, treating low-quality water increases the overall cost of the water,and in many places in the U.S., this additionaltreatment is not economical.

That's where water treatment research comes in.

Research develops technologies and methods toeconomically improve water quality. Applyingthese water quality solutions makes more wateravailable for use (agricultural, municipal, orenvironmental) in the U.S. and Mexico.Technology developed through research is also usedto treat agricultural drainage for return or reuse.This gives Reclamation more options to managegroundwater.

WQIC research staff pursue two goals:

identify processes and technologies to reduce thecost of operating the Yuma Desalting Plant (a 73million-gallon-per-day, reverse osmosis desaltingplant; the site of the WQIC);

identify technologies and processes to advance thestate of water treatment technology, and reduce thecosts to treat impaired waters.

WQIC water sources include custom-mixedformulations, lower-stem Colorado River water andlocal brackish groundwater.

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Our Mission

Ensure Tomorrow’s Water Supplyby Pioneering New Technologies

Exploring Ways to Reduce the Cost andImprove the Efficiency of Treating Water

The Water Quality Improvement Center helps increaseusable water supplies by pioneering technologies andprocesses to improve water quality and make impairedwater usable.

In-House Projects

Program Management &Development

(Authorized under Colorado River Basin Salinity Control Act,Title I)

Title I Salinity Control (TISC) ProgramManagement and Water Quality ImprovementCenter (WQIC) Efficiency

WQIC Technical Support & ProgramDevelopment

The purpose of the TISC Program is to find ways tooperate the Yuma Desalting Plant (YDP) at a lowercost. The WQIC supports that purpose by servingas the primary site for this research. The WQIC is a14,000 square foot building housing membranewater treatment research equipment from bench-scale to full-scale. It is one of only twoReclamation-operated applied research facilitiessearching for desalination solutions. Researchconducted at the WQIC is valuable outside

Reclamation because results can be applied at otherreverse-osmosis desalination plants in the U.S. andaround the world. A Technical Assistance Teammeets twice annually to provide technical guidanceregarding best utilization of the WQIC for testingimprovements to the YDP, developing new watertreatment processes, evaluating improvements toexisting processes, and troubleshooting problemswith existing plants.

The purpose of the WQIC is to support the Title ISalinity Control Research program andReclamation's efforts to accomplish its mission byfinding ways to stretch water supplies and developnew water supply technologies. The WQICprovides critical infrastructure not available at anyother Reclamation office. Development andevolution of the WQIC presents new technicalchallenges, requiring support of process andequipment designs and modifications of thesedesigns, preparation of test programs, review ofpotential CRADAs, chemical engineering analyses,experimental design recommendations, and dataanalyses.

Water Research at the WaterQuality Improvement Center

The Yuma Desalting Plant was constructed to salvagesalty agricultural drainage water and return it to theColorado River, saving water that would otherwise needto be released from Hoover Dam for delivery to Mexico.The water saved is used in communities like LosAngeles, San Diego, Phoenix, Tucson, and many smalltowns adjacent to the River.

Yuma Desalting Plant: Our Primary Focus

FY08 YDP-Related ResearchProjects

Title I Salinity Control Management& WQIC Program Assistance $58,000

Chlorine-Resistant Membranes $60,000

High-Purity, High-RejectionCellulose Acetate Membranes $40,000

Development of Forward OsmosisWater Purification Process $22,000

Upgrading YDP PretreatmentAnd Reverse Osmosis Processes $120,000

Plant Technology Retrofits

Pioneering New Technology

YDP Aluminum-Bronze Life Analysis

YDP Pretreatment and RO Technologies

High-pressure, low pH flows appear to becorroding YDP equipment fabricated fromaluminum-bronze. This equipment includesprocess piping, pumps, and valves. YAO hascontracted with CH2M Hill to evaluate the integrityof plant aluminum-bronze piping systems andrecommend remedial measures. The company willprepare a report that will be used to support futurebudget requests to either repair or replace portionsof plant piping, and/or as a basis for supportingchanges to plant processes to prolong the life ofaluminum-bronze plant features.

When the YDP was designed in the 1970s, thedesign was based on the most reliable watertreatment and desalting technologies available.YDP uses RO desalting and “conventional”pretreatment: partial-lime softening-clarificationand gravity filtration. Over the past 20 years, anarray of advances in RO pretreatment and ROsystems has occurred These technologies need tobe evaluated to determine how suitable they wouldbe for use at the YDP. This research enables YAOnot only to comply with legislation on finding waysto run the plant cost-efficiently, but in satisfyingthat legislation, YAO satisfies its responsibility totaxpayers to protect their investment in the plant.

Forward Osmosis Water Purification Process

Chlorine-Resistant Low-Pressure MembraneStudy

(PATENT)

High-Purity High-Rejection Cellulose AcetateMembranes

Conceived by University of Arizona physicist JohnKessler, unpressurized FO holds great potential forsignificantly reducing capital and energy costs ofdesalting. The proposed project builds on previouswork funded by DARPA. The focus of theproposed project is to pursue a radical new strategyto achieve significant size, cost, and energyimprovements through the development ofinnovative new FO membrane water purificationprocesses. The proposed FO water purificationprocesses will mimic the energy-efficient osmoticprocesses utilized by biological systems. Theobjective of this project is to develop anddemonstrate unpressurized FO desalting processesas quantum improvements over existing pressurizedRO desalting systems.

A primary limiting factor in the spread of RO is thatthe process is energy-intensive, which makes theprocess relatively expensive. One way to reduce thecost of RO is to create low-pressure membranes,which require less energy to operate. Low pressuremembranes do exist, but they are degraded by oneof the most common and low-cost disinfectants inwater treatment - chlorine. Industry describes the“holy grail” of membranes as a low-pressuremembrane that will work with chlorine. Thisproject seeks to perfect the formulation for such amembrane. Upon successful, replicableformulation, the membrane will be patented andmass marketed.

While industry seeks a low-pressure, chlorine-resistant membrane, cellulose-acetate membranescontinue to hold promise, if certain shortcomingscan be overcome. One such shortcoming is that,while the intrinsictransport properties of CA

Engineers designing the YDP in 70s-80s planned forthe YDP to recover 73% of the water it processed.They also planned to use a chemical anti-scalant in theprocess. While the plant was being constructed,Reclamation began exploring new ways to operate athigher recovery levels and with fewer chemicals. Usingour demonstration scale test unit, Pilot System 1, ourengineers perfected a new operating process thatincreased our product water recoveries to 80%,without antiscalants. There is also the potential to getto 85% recovery, though at that level, anti scalantswould be required.

Cutting Costs by Increasing Product WaterRecovery, Reducing Chemical Use

membranes can exceed 99.5% salt rejection, inactual practice CA membranes operate at about95% salt rejection. Modifying CA membranes toachieve 99.5% salt rejection would require onlyrelatively minor modifications in the productionprocess of cellulose to CA in the finalmembrane. This project focuses onfinalizing these modifications andbeginning the process of applying for apatent on the process.

In some locations such as Tucson and theYuma County Foothills area, corrosionproblems have been reported whenColorado River water has been blended

with existing well water sources. The City ofSomerton, AZ, is planning to blend Colorado Riverwater with local well water in the near future. Thisstudy investigates corrosion issues of the blendedwater in order to anticipate possible problem areas.The corrosion properties of various materials ofconstruction in the water treatment, distribution,and customer piping areas will be studied. City ofSomerton well water, Colorado River water, andblended water will be used to investigate corrosionrates under static & dynamic conditions.

The goal of this project is to evaluate the corrosioncharacteristics of typical materials of constructionwith City of Somerton water supplies and blends.The effectiveness of water treatment with theaddition of corrosion inhibitors and other chemicalswill be determined.

(PATENT)

Somerton, AZ Surface and GroundWater Blending Study

(authorized under Technology Transfer Act of1986)

Partner: City of Somerton, AZ, NicklausEngineering, Burns & Roe Services Corporation.

(PATENT) = means patent either is being or will beapplied for.

PartneredResearch Projects

In the early 90s, engineers noticed that YDPmembranes made from cellulose acetate wereinexplicably degrading. They conducted testing anddetermined that iron and chlorine interacted, causingthe membranes to lose integrity. Reclamation changedthe operating process, adding ammonia to formchloramines. This has slowed the degradation to apace that doesn't affect the life of the membranes.

Solving the Mystery of MembraneDegradation

FY97 FY98 FY99 FY00 FY01 FY02 FY03 FY04 FY05

$0

$200,000

$400,000

$600,000

$800,000

$1,000,000

$1,200,000

WQIC Partnered Research Funding FY97-05

Total leveraged Total cash Total in-kind