2013 Malibu Lagoon Restoration Declared a Success

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Malibu Lagoon after completion of the 2012 lagoon project

From 2012-13, the 31-acre Malibu Lagoon underwent a nine-month-long restoration process initiated by California State Parks. Twelve acres of wetland near the mouth of Malibu Creek were drained, wildlife was trapped and relocated, heavy equipment scooped out a thousand tons of trash and fill, channels and bridges were removed, banks were reshaped and native vegetation was replanted. The reconfigured lagoon netted two additional acres of wetlands.

The project was extremely controversial, and many in Malibu hated to see the wetlands drained and dredged, unconvinced that the project was really necessary. There were long hours of impassioned public comments at City Council meetings and demonstrations, but in the end, California State Parks had the say over what happened, and they proceeded.  

In a report released last week, the nonprofit Bay Foundation wrote, “Post-restoration results show the lagoon has been on a positive trajectory for the past six years.” 

“It’s very gratifying, and we’re very pleased with the results,” Suzanne Goode, natural resource program manager for State Parks, said in an interview.

One of the biggest local controversies surrounding the lagoon restoration was the accusation by some that the project caused the seasonal breech of water into the ocean to occur too close to the historic Adamson House, not only causing the property to erode but ruining some of the nearby famous surf breaks.

In answer to that, Goode totally denies that the restoration caused these problems. She said, “It sometimes breeched closer to the Adamson House, even before the restoration. There is no causation there. The city is going to hire consultants to study it. And people going out with shovels at night are not helping the situation, because then the breech is not as deep as it would be if it occurred naturally, and it actually encourages the creek to move over there.”

She also cautions visitors to the lagoon that, “Dogs and drones are both very bad for nesting birds.”

Prior to the restoration, the Bay Foundation reported the Malibu Lagoon was on the Environmental Protection Agency list of “impaired water bodies” for over a decade due to excess nutrients and low oxygen levels. The restoration was considered to be a regional test case for how to save a local wetland by enhancing habitats for native wildlife, improving water quality and eliminating oxygen-deprived areas.

Scientists now conclude that, over the past six years, the restoration project has met or exceeded all of their goals in terms of water circulation (which keeps sediments and nutrients from building up), oxygen levels, the successful nesting of rare birds including western snowy plovers and California least terns, functioning as a habitat for juvenile fish like the federally endangered tidewater goby, a diversity of plants and wildlife, less algae, and a more diverse and sensitive invertebrate community (like starfish, crabs, mussels, etc.).

“We reached all our performance standards, so I’d say the lagoon is now officially restored; but it’s a dynamic system with constant changes,” said Goode. “Like, several years after the restoration, there was a drought and the vegetation was very slow to grow, and now they’ll have to focus on keeping the non-native plants out. This is not an isolated ecosystem, but so far, it’s performed really well.”

The data show that fish populations have become much healthier, with a higher percentage of native fish than non-native fish, and the lagoon is now functioning as a fish “nursery”—there are now much younger versions of the native fish species present, including the endangered tidewater goby.

“The tidewater goby would never even venture into the western channels before,” Goode said. “And now we have a sandy substrate there that [they like]” as well as underwater plants.

Some of the mud flats surrounding the lagoon are there intentionally, as places where certain species of birds can forage for invertebrates. 

Additional monitoring of the lagoon was done after the Woolsey Fire, because scientists were concerned about the effects of too much fire sediment washing down and affecting water quality and plant and animal life. As it turned out, a lot of burned debris circulated in the lagoon for several weeks after the fire, but was all eventually flushed out to sea.

“Before the restoration, the lagoon was retaining sediments and filling in, and now its circulation is much improved and sediments outflow to the ocean,” Bay Foundation Science Director Karina Johnston said in an interview.