How San Diego gets clean drinking water from the ocean
Whenever California is hit by drought – as it always does despite recent rains – many people ask, “What if we get water from the ocean?” “
In San Diego County, this is already happening at a billion dollar facility near the beach.
Recently, as I reported on San Diego’s decades-long quest for water stability, I visited the Carlsbad Desalination Plant, the largest such facility in the country, to see how it works.
The plant, which opened in 2015 after long and difficult development, essentially creates 50 million gallons of potable water every day. Seawater flows through a huge intake pipe straight from the Pacific Ocean, where it is first pumped into reservoirs that work much like Brita filters to remove larger things – like algae – which should not be in drinking water.
Then the water makes its way through a maze of pipes where more impurities are flushed out until virtually nothing is left but salt. This ensures that the water is ready for the high-tech reverse osmosis desalination process, which takes place in thousands of tubes stacked high in a cavernous building. The loud hum of machines echoes through space.
In each of these tubes, there are coiled membranes that act like “microscopic strainers,” as the makers describe them. The water is pushed at high pressure and the membranes trap salt and other dissolved minerals until all that is left is pure H2O.
Finally, the water is treated to make it more like normal drinking water, before it is piped for miles to be mixed with the rest of the county’s water and delivered to faucets across San Diego. The salt brine that remains is mixed with seawater and returned to the ocean.
Currently, a relatively small proportion of the county’s water comes from the ocean – around 8%. Critics say it is one of the most expensive waters around and that operating the plant can harm the nearby ocean ecosystem.
Officials from the San Diego County Water Authority and the private company that runs the plant, Poseidon Water, say adding desalination has cost each household an average of $ 5 per month and they are constantly striving to make the factory more environmentally friendly and low consumption.
Importantly, they say, the ocean is a scarce drought-proof water source that is worth the investment for some level of certainty.
Other communities on the coast have noticed the drought; some explore their own seawater desalination plants, while others plan to remove salt from brackish water in rivers. Another Poseidon water plant is in the works for Huntington Beach.
Read the full article on why San Diego has a lot of water despite a severe drought.
Desalinated seawater has transformed Saudi Arabia, as well as other countries in the Middle East and North Africa. But it can be too expensive for many places that need it.
Recent rainstorms have resulted in a suspension of drought reduction orders imposed during the summer. The storm season, which typically runs from November to March, began early this year, but officials warn there could soon be another period of drought, The Modesto Bee reports.
What we eat
Dotted with colorful candies, these monster cookies are an incredible way to end an adult dinner.
Where we travel
Today’s travel tip comes from Ryan Ver Berkmoes, who recommends Rio Del Mar State Beach in Santa Cruz County:
Facing the ocean, to the left is a seemingly endless expanse of sand that curves all around Monterey Bay. Walk a few minutes and you might see sea otters swaying languidly on their backs in the waves, as well as dolphins and seals prowling around in search of fish as the whales gush out to sea. Watch for fins as great white sharks spawn here. What you won’t see are the people as you step into the expanse of sand.
Look to the right and you see the Cement Boat (otherwise known as the Concrete Ship), a former large cement-built oil tanker that was moored off the beach in 1929 as an entertainment pier. Now crumbling into nothingness, there’s a great little museum where you can learn all the unlikely history.
Add to that a great little deli with sandwiches for beach picnics and it’s the perfect outing. A few years ago my wife and I and a group of our relatives rented houses on the sand for the week of our wedding. Truly unbelievable.
Tell us about your favorite places to visit in California. Email your suggestions to [email protected] We will share more in future editions of the newsletter.
And before leaving, some good news
Buy Nothing groups are flourishing across the country.
These are networks of people, mostly on Facebook, who give and receive things for free – treating the things that take up space in their homes as gifts meant to be shared and treasured.
In a time of isolation, Buy Nothing fosters a sense of quirky community.