1580 Cannon Road, Carlsbad
It’s a mild, breezy afternoon at Agua Hedionda Lagoon. From the vantage of the visitors center, I can see small boats and jet-skis carving whitewater trails off to the west. Right above me are massive towers and transmission lines snaking up the ridge to the Encina Power Station and its 400-foot landmark stacks. Loud buzzing and crackling tell me there’s enough electromagnetic energy here to fry Chuck McGill’s foil suit. But instead of calling Saul, I call Eric Muñoz. I wouldn’t say it’s paradise, but according to Muñoz, it was almost paradise lost, courtesy of a monster mutated seaweed that all but shuttered the lagoon a decade and a half ago.
If every plant grew as easily as Caulerpa taxifolia once did in the lagoon, we’d all have green thumbs. But, exults Muñoz, who worked as a planner for the City of Carlsbad, thanks to anti-Caulerpa activists, we’ve all been spared the Big Green Nightmare. Muñoz is so stoked about the death of a mutated seaweed that he decided to write a book about it: Caulerpa Conquest: A Biological Eradication on the California Coast. He thinks it should be on every bookshelf. When it comes to Agua Hedionda, Muñoz exhibits what might be characterized as pride of ownership. It’s not that Muñoz has a piece of the aquatic pie or was spawned in the shallows of the lagoon; it’s just that he views the aquatic triptych as something of a local treasure. “People need to understand that, between Oceanside Harbor and Mission Bay, the only place where you can actually get into the water in a lagoon or wetland is Agua Hedionda. That would have been lost.”
Muñoz has the history of the not-quite-sleepy lagoon down pat.
“In 1769, Spanish missionaries and soldiers, led by Gaspar de Portola, smelled the debris and decaying fish, so they named it ‘Agua Hedionda,’ or ‘stinky waters.’” Fast-forwarding a couple of centuries, Muñoz says, “I’m sure you’ve seen all the people jet-skiing and waterskiing. The present configuration isn’t natural, but instead, was created so the water entering the lagoon could cool the turbines of the power plant that was built in 1954. Before dredging, it used to be sloughs, not the lagoon you see today. Prior to building the plant, they dredged three different, connected basins: one which opens to the Pacific and extends to the railroad tracks [western], one between the tracks and the freeway [central] and a third, farthest inland [eastern].”
It’s in the eastern basin that the marine menace manifested, bearing fruit to a “green” tableaux welcomed by no one.
Muñoz sets the scene for what he views as a megadebacle narrowly avoided: “It’s technically an estuary, the western terminus of a watershed. Depth, which is tide-dependent, can be as much as 20 feet but is typically 8 to 12 feet. Rainfall has minimal effect.”
The lagoon, which, according to Muñoz, contains about 390 acres of water surface, has the same salinity as ocean water, with a touch of brackishness at the eastern end where it’s fed by the confluence of Agua Hedionda and Calavera creeks. Water temperatures, 58–70 degrees, are identical to those of the ocean.
It’s not all Eden, of course, because for most San Diegans, Agua Hedionda is overshadowed, at least visually, by the ginormous tower of the power plant that uses lagoon water to cool its turbines. There’s also dredging.
“Cooling requires full circulation of the water flowing from the ocean under the Tamarack bridge,” Muñoz says. “However, when tides and wave action cause sediment build-up at the mouth of the lagoon, cooling is impeded. As a result, the lagoon has to be dredged every two to three years, with the sand placed on the nearby Carlsbad beaches. Last winter, large waves moved a lot of sand back into the lagoon.”
Revealing that he’s no kook, Muñoz adds, “‘Warmwater Jetties’ [named for the warm outflow via discharge pipes] is the name of a surf spot, a really good wave that breaks off the edge of the jetties.”
Righteous breaks aside, “What’s the deal with this evil seaweed?” I ask Muñoz. “Why should San Diegans give a slimy stolon about Caulerpa taxifolia?” And then it’s off to Marine Biology 101, a course I never took.
“Caulerpa is the genus, and taxifolia is the species, one of dozens; it’s a naturally occurring seaweed in tropical areas, where fish feed on it and keep it in check. But in the ’70s in Germany, the Stuttgart Zoo noticed a mutant strain and then cultivated it, ending up with a clone that was more robust than its natural counterpart. It was a neon-green. It was able to withstand much colder water as well as lower light conditions.” As a result, recounts Muñoz, it soon found its way into aquariums, where its bright color, ability to grow without maintenance, and lack of palatability to fish were positive attributes.
By 1980, taxifolia had been distributed to several European countries, including Monaco, where it was housed at the National Aquarium. In 1984, the Monacans released the seaweed into a cove in front of the facility, from which it rapidly spread in the open waters of the Mediterranean. “It was probably accidental,” opines Muñoz, “but nevertheless, we learned that you don’t want to dump the contents of an aquarium into the natural environment. Invasive species might find a niche where there are no predators, so they overtake and dominate.”
Such is the case with the Caulerpa taxifolia clone, which, once introduced, rapidly overwhelms its surroundings, forming masses dense enough to smother coral reefs. “Where there’s Caulerpa,” quips Muñoz, “there are no fish.”
In the interim, says Muñoz, humble Agua Hedionda Lagoon, already a destination for aquatic pleasures, had emerged as one of the birthplaces of wakeboarding, as well as a mecca for jet-skiing, and later, stand-up paddleboarding. It’s a nonpareil recreational realm, asserts Muñoz, along with an essential marine nursery that San Diego County stood to lose if the prolific seaweed had been allowed to run roughshod.