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Facets of ‘pure water’. The Tustin PFAS Treatment Plant is one of several PFAS remediation projects Caliagua is currently engaged in.
Diving Into the Future: Pure Water Southern California
If you’re living in the greater Los Angeles area, your water comes to you via the Joint Outfall System. This is a vast network of 1,200 miles of trunk sewers and seven water treatment/ water reclamation plants which meet the water needs of 73 cities and unincorporated county territory. The A.K. Warren Water Resource Facility is a critical part of the overall network. It provides centralized processing of solids removed during wastewater treatment for all of the JOS plants. Along the way, the Warren Facility also produces electricity and reusable biosolids in the process.
Its capacity is mind-boggling; approximately 260 million gallons of wastewater are treated every day at Warren. If you filled Dodger Stadium to the brim with water, it would still require 21 Dodger Stadiums before you had this much treated water!
Presently, all that water is pumped from the Warren Facility into the ocean at a point nearly two miles off of the Palos Verdes peninsula. Three climate-related factors, decreased precipitation, increased evaporation, and more frequent droughts mean we need to manage our water better than this. Annual precipitation is projected to decline between 5% and 10%. The good news is that, by changing the way we manage our water, Southern California will continue to meet the challenges of living in an arid climate.
Rapid and multi-faceted. Disruptive and transformational. Market driven and investment fueled. These terms all describe the way industries across the globe, and in many sectors are innovating to address the climate challenge. Working together, the Metropolitan Water District and the Los Angeles Department of Sanitation are keeping pace by adopting new technologies and renewing aging infrastructure.
Planned Technologies
Underway since 2022, Pure Water Southern California is already under early construction. The new facility will make use of some newer, advanced technologies including:
· Microfiltration/Ultrafiltration
· Reverse Osmosis (RO)
· Ozone or Advanced Oxidation Processes (AOP)
· Ultraviolet (UV) Disinfection
This blog has discussed these technologies previously; you can read more about them in Caliagua’s July, 2023 article, “Water Filtration: Clean Water in California”
Here’s a summary of the major changes how our water will be treated:
The Warren Facility presently purifies only 10% of its treated water. Once running, Pure Water Southern California will yield nearly six times this amount, with an estimated daily yield of 150 million gallons of drinking water. This is enough to serve more than 500,000 homes. Beyond drinking water, purified water can also be used for groundwater replenishment, industrial purposes, and even as an additional supply into Metropolitan’s water treatment plants. It is projected that the Pure Water project will be completed by 2032 at an estimated cost of between $4.8 and $9 billion. The state of California has already funded $130 million of this amount.
As much as 60% of the purified water may be used for ground water replenishment, while the remaining 40% will be directed towards municipal water treatment facilities for blending and distribution as drinking water. While specific details about well and spreading facility locations might be subject to change based on ongoing planning and environmental considerations. Presently, there are six such locations. See the inset diagram. The two locations nearest to metro Los Angeles include:
West Coast Groundwater Basin: This basin is located near the city of Carson and could be a target for injection wells.
Central Groundwater Basin: Located in the city of Long Beach, this basin could also be a candidate for groundwater replenishment using injection wells or spreading facilities.
There are four other locations as well.
Treatment of Solids
An estimated 138,000 tons of solids are processed each year at the Warren Facility, and about 50% of these solids are used for soil amendment. Roughly 25% of these solids are used for composting, and the rest is landfilled.
The traditional methods of water extraction and solids processing used at A.K. Warren were once leading edge. They include:
Thickening: The initial step often involves thickening the removed solids. This process concentrates the solids and reduces their volume, making them easier to handle and transport. Thickening can be achieved through gravity thickening tanks or mechanical thickening devices.
Digestion: The thickened solids then undergo anaerobic digestion. In large, sealed tanks, microorganisms break down the organic matter present in the solids under oxygen-depleted conditions. This process reduces the volume and stabilizes the solids, making them less odorous and easier to manage. Digestion also produces biogas, a renewable source of energy that can be used to power some of the facility’s operations.
Soil Amendment:In some cases, the digested sludge may be further processed and treated to meet specific quality standards.
Treated biosolids can be a valuable soil amendment, providing nutrients and organic matter to improve soil health for landscaping or agriculture. However, stringent regulations govern the use of biosolids as fertilizer to ensure public safety and environmental protection.
Composting: Composting facilities can sometimes accept biosolids and co-compost them with other organic materials like yard waste or food scraps. The resulting compost can then be used as a soil amendment.
Landfill Disposal: If beneficial reuse options aren’t available or suitable, the final option might be disposal in a sanitary landfill. Landfills are designed to contain waste and minimize environmental impacts.
State of the art processes will be in use once Pure Water Southern California is active.
Implementation Schedule
Overall, the Pure Water project has a three-phase development cycle. We are presently nearing the end of the first phase, Environmental Planning and Review. The second phase, design and construction is already underway, and is expected to run through 2031. Finally, the last phase, start-up and operations is projected to occur in 2032. There are also efforts being made to further expedite the project in order to bring at least some elements online as early as 2028.
When completed, it will be one of the biggest water recycling projects in the world, showcasing advancements in wastewater treatment technology.
Dedicated to Clean Water for Over 45 Years
After 45 years, Caliagua remains a vital part of Southern California’s clean water industry, helping our community adapt to our region’s constantly evolving and growing demand for irrigable and potable water. We keep pace with the technological changes driving our industry, and our workforce remains young, professional, and focused on exceptional results. Have a project you’d like to discuss with us? Contact Gus Bruner (gusbruner@caliagua.net) or Cory Wolfrom (cwolfrom@caliagua.net )!