Questions surround lagoon restoration plans

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Reworking the flow of the Malibu Lagoon with several channels is proposed as part of restoration plans for the lagoon. Heather O'Quinn / TMT

Some residents voiced skepticism about proposals to improve water quality in Malibu Lagoon by digging and redirecting its channels, but others accepted the move as a good first step.

By Susan Reines/Special to The Malibu Times

Residents greeted Malibu Lagoon restoration plans with widely varied reactions last week, with some saying a proposal to dredge large portions of the over-vegetated water body would destroy marine life, while others called it the first baby step toward detoxifying the water.

Three alternative proposals presented by consultants from engineering firm Moffatt & Nichol involved digging into the lagoon to widen and deepen its channels, actions, consultants said, would speed water flow and curb the growth of vegetation that releases excess carbon dioxide into the water.

Some members of the Lagoon Restoration Working Group (formerly called the Lagoon Task Force) said digging into the lagoon was too risky because it was unclear how the construction would affect plant and animal life.

“The various alternatives seem to have very iffy consequences,” Muriel Kotin said. “So my reaction would be, yes, we need to do something, but if we’re not sure of the consequences, maybe we should try to do minimal.”

Others characterized the disruption to wildlife as temporary, however, and said the long-term benefits of reshaping the lagoon channels were worth short-term setbacks.

“Whatever is disturbed by dredging is going to grow back, whether it is in the same place or some place else,” said Shelley Luce, director of science and policy at Heal the Bay. “This is going to improve the water quality and hydrology, which is good for habitat.”

Consultant Chris Webb outlined three alternative plans, which involved digging out the lagoon to different degrees. One alternative would widen and deepen the lagoon’s western arms, where water often becomes stagnant, and connect two of the arms to allow water to circulate between them. Another would make the three small arms into one broad channel, which would be flushed with water flowing from the commercial drains on the other side of the Pacific Coast Highway. A third reworks the arms into one large channel with small offshoots and moves the mouth of the lagoon to minimize the amount of sediment that fills into the arms.

The restorations-which are being funded by a grant from the Coastal Conservancy on behalf of State Parks and directed by environmental organization Heal the Bay and committees of residents and scientists-include islands for birds and some other new habitats, like mud flats.

Webb said the six scientists who make up the Lagoon Technical Advisory Committee deemed the third alternative most cost-effective and beneficial to habitat, although they suggested studying the possibility of adding flushing from the commercial drain into that alternative.

The alternatives were developed in response to the task force’s stated priorities of improving the lagoon’s tidal flushing, circulation, holding capacity and salt marsh acreage, Webb said.

Some members of the task force said the recommendations they gave to the consultants in June had focused more on habitat and less on water flow, however.

“I’m concerned to see that so much has changed since June,” Marcia Hanscom, of Wetlands Action Network and member of the lagoon work group, said, adding that she had requested that lagoon restorations affect as little wildlife habitat as possible.

“There were not complete habitat studies done, and we were told that was because there was not enough money,” she said. “But now you have money to do all this dredging. I would like to see something less expensive, less intrusive.”

Another lagoon work group member, Robert Roy Van de Hoek, repeatedly burst out with interruptions during Webb’s presentations, challenging his scientific methods and conclusions. Van de Hoek said there should be complete studies of marine life, and restoration plans should be based around improving habitat for endangered species.

There were also discrepancies over some of the consultants’ basic assumptions-that the lagoon is open in the winter and closed in the summer, for example.

Longtime Malibu surfing teacher Mike Avatar said that, based on years of teaching in the ocean below the lagoon, he had not observed the lagoon’s mouth opening to be controlled by the seasons.

“It’s not seasonally open,” he said. “It’s open when it rains.”

The consultants’ proposals to improve water flow were based on the lagoon’s mouth to the ocean being generally open half the year and closed the other half.

Heal the Bay Staff Scientist Craig Shuman said the proposals were a starting point, and if one alternative is chosen, it will be subject to environmental review.

“If this isn’t an enhancement as defined by the law, then it won’t go forward,” Shuman said. “But if we want to make progress, we have to start somewhere.”