A joint effort of the

Orange County Water District and Orange County Sanitation District

California Water

1913

1939

Delta1960s

Central Valley

Project1931

State Water Project 1960s

• Imported Supplies• Groundwater• Storm Water• Water Transfers• Desalination• Water Recycling

Orange County Water District

•OCWD, formed in 1933, is responsible for managing and protecting the Orange County groundwater basin

•OCWD encompasses 229,000 acres (925 km2) in the lower watershed of the Santa Ana River (SAR)

•Orange County groundwater basin provides water for over 2.4 million people

• Northern and central Orange County receives 62% of its water supply from a large groundwater basin managed by the Orange County Water District

• South of the city of Irvine, Orange County is 95% dependent on imported water from Northern California and the Colorado River

Orange County’s Water

Seawater Barrier

OCWD’s basin is hydraulically connected to the ocean

• OCWD has purified sewer water to drinking water

standards and injected it into a pressurized

underground sea water barrier since the 1970s

• Seawater began to go around the barrier protecting

the groundwater

• Eight new injection wells were needed to increase

barrier injection from 15 to 35 million gallons per day

to protect groundwater

Ocean Water

Seawater Barrier

Injection WellInjection Well

Intrusion BarrierIntrusion BarrierSea LevelSea Level

Desired SeawaterHolding Point Injection

Wells

Talbert Aquifer

ProductionWells

Main AquiferMain Aquifer

BetaBeta

LambdaLambda

Talbert

Alpha

Pacific OceanPacific Ocean

Current Extent of Seawater Intrusion

Seawater Intrusion

The Two Agencies

Orange County Water District Provides local water retailers with a reliable, adequate, high-quality groundwater supply at the lowest reasonable cost in an environmentally responsible manner

Orange County Sanitation District Protects public health and the environment by providing effective wastewater collection, treatment, and recycling

Long History Of Partnership

• Orange County Water District (OCWD) & Orange County Sanitation District (OCSD)• Both serve the same 2.4 million residents plus

businesses and industries in northern and central Orange County

• Came together on Water Factory 21 in 1975• OCSD contributed half the capital cost to the

Groundwater Replenishment System (GWRS) to avoid building an additional ocean outfall

• Finished as a dedicated team on the GWRS

Why Do We Need The GWRS?

• Extended drought

• Imported water shortages

Colorado River losses

State Water Project losses

Environmental restrictions

Potential levee failures• Local Projects lessen

dependency on outside sources

San Luis Reservoir before and now. Gov. Schwarzenegger declares emergency

What Is The GWRS?

• New 70 MGD (265,000 m3/day) advanced water purification facility

• Takes sewer water that otherwise would be wasted to the ocean, purifies it to near distilled quality and then recharges it into the groundwater basin

• Provides a new 72,000 acre-feet (88,000,000 m3) per year source of water, which is enough water for over 500,000 people

• Operational since January 2008

Microfiltration System

• 86 MGD (325,500 m3/day) Siemens CMF-S Microfiltration System

• Tiny, straw like hollow fiber polypropylene membrane

• Removes bacteria, protozoa, and suspended solids

• 0.2 micron pore size

• In basin submersible system

Reverse Osmosis System

• 70 MGD (265,000 m3/day) Reverse Osmosis System

• 3 stage: 78-48-24 array

• Hydranautics ESPA-2 Membranes

• Recovery Rate: 85%

• Removes dissolved minerals, viruses, and organic compounds (incl. pharmaceuticals)

• Pressure range: 150 – 200 psi

Direct Photolysis/Advanced Oxidation

• 70 MGD (265,000 m3/day) Trojan UVPhox System

• Low Pressure – High Output lamp system

• Destroys trace organics

• Uses Hydrogen Peroxide to create an Advanced Oxidation Process

• After treatment, water is so pure we need to add minerals back - lime

Regulatory Oversight

• Regional Water Quality Control Board issues permits for recycling

• CA Department of Public Health regulates drinking water and establishes reclamation criteria Treatment TOC limit Travel time Blending

• No federal role regulating reuse• CDPH hearing findings and

recommendations incorporated into permit by Regional Board

Independent Advisory Panel

• Appointed by National Water Research Institute

• Leading experts in hydrogeology, chemistry, toxicology, microbiology, engineering, public health, public communications and

environmental protection• Review operations, monitoring and water quality• Panel makes recommendations to OCWD and

regulatory agencies to assure quality and reliability

Start-up of the GWRS

• Commissioning began fall 2007

• Injection into seawater intrusion barrier and spreading in percolation basins began January 2008

• Flow limited by available effluent and diurnal variability

• Tracer study verified travel time from spreading basins to nearest well

• Trickling filter effluent pilot MF study• Blend 80% activated sludge 20%

trickling filter effluent, began May 2008

GWRS Proven Reliability

• California Department of Public Health developed permit requirements

• Test for over 200 compounds with all results well below permit levels or at non-detection (ND) levels • 28 Volatile Organic Compounds – All ND• 39 Non-Volatile Synthetic Organic Compounds – All ND• 8 Disinfection By-Products – All ND• 10 Unregulated Chemicals – All but one ND, all below permit

levels• 51 Priority Pollutants – All ND• 16 Endocrine Disrupting Chemicals and Pharmaceuticals – All

ND

Keys To Success

• Project meets Orange County’s water needs

• Board of Directors insistence on highest quality water ($480 million shared capital costs)

• History of successful water reuse in Orange County with Water Factory 21 recycling facility

• Groundwater basin provides natural and psychological barrier

• Successful outreach from conception of facility, to construction and finally commissioning

Benefits Of GWRS

• Creates a new water supply

• Reuses a wasted resource

• Expands the seawater barrier

• Increases water supply reliability

• Offsets imported water cutbacks

• Costs comparable to imported water

• Saves half the energy over imported water or desalinated seawater

• Improves quality of water in the basin

Public Outreach

• Many projects stopped by public and political opposition

• Outreach began early, over 10 years prior to start up

• Researched public concerns• Face to face presentations• Community leaders• Measured effects of outreach• Community support• Outreach continues today,

assisted by media interest

Strong Community Support

No active opposition

100% support from cities in OCWD service area

100% support from OC State and Federal elected officials

100% support from Chambers of Commerce & OCBC

Many major businesses, Edison, Semper Energy, etc.

All major environmental groups (Surfriders, Coastkeepers)

Several health experts, medical doctors, hospitals,

pharmacists and scientists supporting

Several key minority leaders

Educational, religious, police, fire leaders

More than 200 community groups like Kiwanis, Rotary, etc.

OC Tax, AARP, OC Farm Bureau & others

Proactive face-to-face outreach with more than 1,200 presentations, 700 tours and many news stories that resulted in:

What We Learned About Public Perception

• People do not know about water supply needs First must explain the need

• Messages must address health and safety• Orange County citizens want reliability, local

control, and high quality water• Women, mothers, minorities, and elderly are

key audiences• Face-to-face presentations are best• Avoid jargon• Testimonials from outsiders are important –

especially medical/public health• “Reverse osmosis” elicits positive response• Word “purified” better than reclaimed, reused,

etc

What Have We Learned From GWRS?

• Public can accept indirect potable reuse projects if: need is clear

outreach is effective and ongoing

politicians and community leaders make commitment

quality is higher than alternatives

regulators have ongoing oversight independent scientific review

• The more people know about GWRS the more they accept it

GWRS Aerial View