Last November, I had the opportunity to chaperone my daughter's class when they visited the West Basin Water District's Edward C. Little Water Recycling Facility in El Segundo, California.
Here's a Google Earth view of the area. Most of the waste water from western LA county goes to the Hyperion Sewage Treatment Plant for removal of solids and biological treatment with bacteria that eat the smaller particles before settling to the bottom of the holding tanks. The water is then pumped to the water recycling plant marked by the red asterisk (*).
The world's second largest Whole Foods (marked with the red WF) is adjacent to the water recycling plant, proving that there is absolutely nothing smelly or off-putting about the place. Some of this country's most expensive real estate is in the southwest corner of this picture.
Notice the density of the residential neighborhoods. The small plots save tons of water, both because we use less for landscaping, and because of the embedded water in the gasoline we don't consume.
Here's one of the giant tanks on the site. I am not sure if this is the beginning or the end for the water's sojourn here.
The water goes through a two-step filtration process, first traveling through hollow fibers held together in these rods to remove the larger bacteria and viruses.
It gets scummy looking during the process.
A dispersant agent is used in this step to keep things free-flowing.
The water then undergoes a second filtration, using reverse osmosis through these filters. The water is pushed with high pressure from the outside to the inside. The clean water flows out of the center tube.
Here are some filter rods awaiting use.
These are in use.
This removes the smaller bacteria and viruses as well as salt and some pharmaceuticals. Yup, we collectively take a lot of drugs (both legal and the other kind), excrete them, and then flush them down the toilet. It all ends up here.
The water is then treated with ultraviolet light to break up the pharmaceuticals and kill any viruses that survived the earlier processes. UV treatment can create radicals, which are corrosive to pipes. The water pH is adjusted with lime as a buffer agent to prevent that. See the characteristic blue-green lime color of the treated water?
It reminds me of the swimming holes at the base of the water falls in Havasu canyon. (Havasupai means people of the blue-green water.)
OK, now let's talk about recycling. The outflow is piped around the Southland for landscape irrigation, flushing and other industrial uses (like cooling water at the many refineries in our region).
It's no accident that the Chevron refinery and two golf courses are located so close to the water recycling plant. They use reclaimed water. In fact, many office buildings in our region use reclaimed water for both outdoor irrigation and flushing toilets. LA Air Force Base and Toyota USA Headquarters are two notable sites.
We also sit upon a giant aquifer, which we pump for drinking water. During the rainy season, rainwater percolates down to recharge the aquifer. (Actually, too much of it runs off into the storm drains before they get a chance to percolate into the ground, but that's another discussion.)
At the coast, it is always a battle against salt water incursion into the fresh water aquifer. That's why we have built a line of injection wells (blue dots) along the coast.
The treated waste water is injected at the bottom of the aquifers. We also pump water from the top of the aquifers for drinking water. About 30-40% of my local water supply comes from these wells and directly from the recycling plant.
At the plant, they are careful to show the injection wells and water source wells on different pictures. ;-) Perhaps they think we will be grossed out? I am not bothered by it. In fact, I am proud of the ingenuity demonstrated in this water recycling plant.
Did you know that 20-25% of California's electricity usage is to move water around? The more we recycle our water, the lower our carbon and water footprints.
As we walked around the plant, I found many golf balls
- Blog Action Day 2010
- Chance of Rain (lots of links to all things water in CA/NV)
- Breathing Treatment: No New Sources
- BMGM: Walking My Watershed
- BMGM: Water Hazard
- BMGM: More biological experiments
- West Basin Water District official site
- West Basin: About recycled water
- Hyperion official website
- Havasupai Tribe official website (one of our greatest camping trips ever!)
- World Eater Day 2012