Chris Peregrine walked down a gentle slope in goat canyon just north of the U.S.-Mexico border. He pointed to a thick steel cable that spans the basin that cross-border flows frequently fill.
“Yeah, we have an anchor on either side,” Peregrine said, "And a heavy-duty cable that connects the trash boom and lets it span across the entire sediment basin.”
The trash boom is fencing on top of pontoons that are designed to stop everything that floats. There are tires here and there. But single-use plastic bottles dominate the trash captured here, though that is not all.
“We’re also seeing quite a bit of foam," Peregrine said. “You can see that there’s a couple of different types of foam here. This is typical polystyrene. But then also we see a lot of this type of insulation type of foam.”
The trash boom was installed in 2005 to keep sediment and garbage from filling up and fouling the nearby Tijuana River Estuary.
“We’re about a half-mile away from an area that has the saltwater influence of the estuary right now,” said the state parks worker.
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If the sand and trash were allowed to flow unchecked into the estuary, it could completely choke off the ability of the habitat to function.
“That mixing, that saltwater coming on a high tide and going out on a low tide, and that saltwater mixing with the freshwater of the Tijuana River, is what makes this place so biologically diverse and so special,” Peregrine said.
The plastics and sand accumulate in the basin and then state and county officials use heavy equipment to remove the trash and scrape off a layer of sediment. And this is not the only front in the battle to capture trash coming across the border. It is also happening in a Tijuana community about a mile south of the border.
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“It’s basically a canyon where people have settled and it goes all the way up and it has three different names,” said Fay Crevoshay, with the environmental group Wildcoast. “(It's called) Los Laurelles, a La Cranes and Las Flores. It’s one tributary.”
An international grant allowed the community there to build a trash boom inside a concrete sediment collector. The idea is to stop the garbage from evening reaching the United States.
“It’s stopping the sediment and trash that comes floating with the water and also under the water,“ Crevoshay said. “We don’t stop the water. The water continues to flow down the Tijuana River, but that way all these plastics and waste tires and stuff don’t go to the river and from there to the ocean.”
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A local organizer is helping teach the community in Mexico how to clean up the water.
Wildcoast's Rosario Norzagaray often trades small food items for plastics in an effort to create an economic incentive to pick up the trash. And they have to protect themselves if they go into the concrete collector.
“Per the rules, per the protocol, the team that arrives to work specifically in the area of the desander (water grit trap) must wear safety equipment,” Norzagaray said in Spanish.
Teaching the community how to manage the trash boom is only part of the equation.
“The community has to raise awareness regarding a change of habits, a change in behaviors; in how are they currently handling their waste and how it directly creates the contamination problem in the estuary,” Norzaggaray said.
Even with these efforts, the estuary on the U.S. side of the border remains under assault.
Every time it rains trash flows down the Tijuana River Valley, the main channel as Peregrine calls it.
“There’s no formal facility here to capture trash,” Peregrine said. “So in Goat Canyon, we can clean the trash out of an area with heavy equipment. But when you come to an area like this that’s currently supporting nest species, right in amongst these trash flows it becomes very challenging to clean up.”
And while the trash is tough to clean out of the thick riparian habitat, it does not necessarily stay here in the heavy brush near Dairy Mart Road.
“It’s going to start making its way further downstream,” Peregrine said. “As it makes its way downstream it breaks up into smaller and smaller pieces. And ultimately it’s working its way out into the environment and into the ocean.”
Peregrine hopes that a combination of efforts around the estuary and in Mexico will help reduce the amount of trash that finds its way into the estuary.
If that happens the estuary could become the biological jewel it is intended to be.
