Regional Recycled Water Advanced Purification Center: Phase I
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A Look Inside How It Works
The Pure Water demonstration facility uses a 3-step purification process. The first step involves membrane bioreactors, the second step is reverse osmosis, and the third step is ultraviolet disinfection and advanced oxidation. What makes this treatment process innovative is the use of MBRs in water reuse treatment. They have been used in the wastewater industry for decades but are new to the world of water reuse. Their effectiveness also has been studied internationally in countries like Australia and Singapore, where the technology effectively purified water for eventual consumption. The MBRs are able to remove materials dissolved in water like organic matter, nitrogen and other particles down to a microscopic level. Their eventual use in the purification process, once granted regulatory approval, is what makes the Pure Water process innovative.
The Purification Process
Membrane bioreactors use biological processes and membrane technology to clean water.
Air is added to biological process tanks to create an environment where helpful microorganisms thrive. The microorganisms remove organic material and nitrogen compounds, such as ammonia and nitrate.
The water flows into membrane tanks where thousands of straw-shaped membranes with tiny pores filter and remove microscopic materials, including microorganisms and other particles. Many are smaller than 1/100 of a grain of sand.
Reverse osmosis is often considered the core water purification process and eliminates more than 99% of all impurities. Water leaving the MBRs is pressurized with a series of pumps and applied to tightly wound membranes, which selectively allow water molecules through the membranes’ pores, while blocking the passage of microscopic materials, such as bacteria, pharmaceuticals and salts.
Reverse osmosis is widely used to purify water, most commonly to remove salt in seawater desalination projects. It is also used in many bottled water processes and groundwater replenishment projects.
Ultraviolet Light/Advanced Oxidation
Ultraviolet light is a powerful disinfectant used to inactivate viruses in water. When ultraviolet light is combined with a strong oxidant, either hydrogen peroxide or sodium hypochlorite, extremely reactive molecules are created. These molecules remove trace chemical compounds that may remain. The combination of the ultraviolet light and strong oxidant is referred to as the Advanced Oxidation Process. This is a final polishing step that ensures the water is safe and highly purified.
The Los Angeles County Sanitation Districts’ Whittier Narrows Water Reclamation becomes the first plant in the U.S. designed to recycle water and recharge groundwater basins.
Metropolitan launches the Local Resources Program, which provides financial incentives for local projects like recycling, groundwater recovery and desalination and encourages what will become more than 100 different projects throughout the Southland to date.
Metropolitan initiates discussion and technical studies with Sanitation Districts for what is named the Regional Recycled Water Program.
Pilot studies on purification technologies and feasibility studies begin and conclude in 2016.
Demonstration plant construction starts.
The demonstration plant comes online.
Metropolitan’s board approves a four-year environmental planning phase.
Metropolitan and the Sanitation Districts complete the first phase of testing at the demonstration plant.
Pure Water Southern California becomes the official name of the program. Other milestones include $80 million in funding from the State of California and the launch of the program’s environmental review process.
Partner agencies will consider the Environmental Impact Report in decision making, and construction could start as early as 2025.
Select Pure Water Southern California facilities may be online.
Operations are scheduled to begin.
Innovation at Work
Pure Water Southern California is novel in its scale and purification process, but the concept of recycling water is not new. Several communities across Southern California, including some in Los Angeles, Orange and San Bernardino counties, - not to mention uses worldwide - use recycled water for drinking and other applications.
Click on the to explore various innovative programs in development and operation throughout our region.
The City of San Diego is constructing a new water recycling plant and associated facilities to produce 30 million gallons of purified water daily. This is the first phase in its multi-year Pure Water Program that will provide one-third of the City’s water supply by 2035.
The Edward C. Little Water Recycling Facility purifies water from the City of Los Angeles' Hyperion Wastewater Treatment Plant and produces water for irrigation water, industrial use, and adding to groundwater to prevent seawater intrusion.
The Groundwater Replenishment System is the world's largest advanced water purification system. The system produces 100 million gallons of purified water daily to help refill groundwater basins. It is currently undergoing an expansion to 130 million gallons daily.
The Albert Robles Center purifies and recycles approximately 14.8 million gallons of water daily, which is used for groundwater replenishment. The Center is a multipurpose and multi-benefit site which includes an Advanced Water Treatment Facility, a fully digital Learning Center, and a water-efficient Demonstration Garden.
Pure Water Oceanside is an advanced water purification program that purifies recycled water to create a new, local source of drinking water. Between 3 to 5 million gallons of drinking water is created each day, enough to provide 32% of the City of Oceanside’s water supply.
Recycled water makes up more than one-third of Eastern Municipal Water District’s water supply portfolio. Recycled water is used for agriculture, irrigation and industrial use. EMWD is also planning to produce purified recycled water for groundwater replenishment through its Purified Water Replenishment program.
The City of Oxnard’s Advanced Water Purification Facility produces recycled water for irrigation of parks, medians, golf courses and athletic fields; watering of agriculture crops; and process water for local industries. The City plans to expand its facility and use recycled water for groundwater replenishment.
IEUA receives and cleans more than 50 million gallons per day of wastewater, which is then used for agriculture, municipal irrigation, industrial uses, and for groundwater replenishment. IEUA is also planning to provide additional purified recycled water for groundwater replenishment by 2028.
The East County Advanced Water Purification Program will create a new drinking water supply utilizing state-of-the-art technology to recycle the region’s wastewater. The project is under construction and scheduled to be online in 2025.
The Los Angeles County Sanitation Districts began replenishing groundwater with recycled water in 1962 at their Whittier Narrows Water Reclamation Plant. Recycling has since expanded to 10 treatment plants and they have recycled over 1 trillion gallons.
Environmental Review Documents and Resources
Awards & Recognitions