Posted on July 15, 2026
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SEAL BEACH, Calif. — Scientists said wetlands can slow down storm surges, absorb pollutants and even offer protection for infrastructure as a buffer between the ocean and roads.
That’s why for the past decade, some scientists have been working on a solution for a wetlands area in Seal Beach that had often been underwater.
Scientists studying the Seal Beach National Wildlife Refuge for years have observed that sea level rise at this site was three times higher than in surrounding areas.
“It meant that at the highest of high tides there wasn’t marsh habitat enough above the water line,” said Cal State Long Beach biology professor Christine Whitcraft.
As a result, Whitcraft said the area at the Naval Weapons Station Seal Beach started seeing impacts such as water across roads and other infrastructure. It also started affecting the availability of nesting areas for a federally endangered bird, the Lightfooted Ridgway’s Rail.
Some reasons this area has seen higher sea level rise are for three reasons.
Whitcraft noted that it’s in an area near faults which can cause movement.
“Historically, this site has oil and gas extraction,” she added. “And that can lead to subsidence that had occurred a little bit. And that’s just sinking of the land. In addition, the way that a marsh keeps pace with the ocean level is to have mud come down the rivers and get spread over the marsh. In this case, our river is decoupled, or no longer connected to this site. So, the supply of mud is very low.”
As part of a pilot project that began a decade ago, scientists started applying a thin layer of sediment (mud or sand to match the existing sediment) to the surface area of the marsh in an attempt to raise its elevation.
The method is called “sediment (or soil) augmentation.”
Whitcraft, along with naval biologist Chloe Van Grootheest, and a number of agencies, has been working on the project and helping to monitor it for the past decade. They have been measuring elevations, water flows, and keeping track of plant growth and the species using the area.
Grootheest said that while initially the growth was slower than they had hoped, now, “It’s growing pretty tall and pretty dense and healthy, for this site at least. And we’re finding that we’re getting more nests for the light-footed ridgeway rails.”
The bird is federally endangered.
After a decade, Whitcraft said the team is thrilled with the results of the pilot project.
“There are plants, there’s birds. It’s out of the water at the highest tides.” she said. “When you come back out after ten years and you see that in changing the conditions and in planting plants and in raising the elevation that it worked, it is kind of like you passed a test.”
While this method worked in the local area, Whitcraft explained that it doesn’t necessarily mean it would work in other marsh areas. But she said this pilot project has offered many learned lessons in how to potentially do this in other areas, including applying for permits, timelines, etc.
Whitcraft added that there might be plans to apply this method to other areas within the National Wildlife Refuge.
