Bolsa inlet does no harm

A year of testing has shown restoration efforts in the Bolsa Chica Wetlands have not increased bacteria levels in nearby waters, according to a conservationist group that has done regular testing on the tidal inlet to the wetlands, which opened last August.

Members of the Bolsa Chica Conservancy gathered at the Bolsa Chica Interpretive Center Tuesday to unveil their findings, calling the data strong evidence that the wetlands haven’t had a negative effect. When the inlet was opened, some feared the long-stagnant waters might harm the nearby environment.

Those fears haven’t been borne out, said Victor Leipzig, a biology professor who is co-chairman of the group’s Science Committee and Water Monitoring Team and is a columnist for the Independent.

“There’s good news,” he said. “The water going out of the Bolsa Chica tidal basin generally has no more bacteria than the water rushing into it. It does not seem to be a significant source of contamination.”

Trained monitors took samples right at the Pacific Coast Highway where water rushes in and out of the inlet with the tides, Leipzig said. Then they sent what they collected to water monitoring group Orange County Coastkeeper for results.

The tests found that three kinds of “marker” bacteria, which regularly show up alongside harder-to-detect infections in the water, appeared in the tides in no greater numbers than before the inlet was opened. Numbers are right in line with the rest of the beach, and two of those three bacteria were regularly tens or hundreds of times lower than state-mandated levels.

Only one kind of bacterium, enterococcus, ever exceeded state safety levels, five times out of the 18 measuring dates. But that level is common in the area, and data shows three times out of five, water coming out of the tidal basin was cleaner than water going in — suggesting the problem lies elsewhere than the wetlands.

Normally such bacteria comes from urban runoff or sewage contamination, but in this case the biggest worry centered on a bird’s rear end. The largest likely source of contaminating bacteria in the area was avian feces, said David Carlberg, also a member of the committee.

“They used computer models to calculate how many birds’ fecal matter might tip the scales,” he said. “But the effect was minimal.”

Bacteria isn’t the only kind of pollution possible, Carlberg said. His group has also started measuring hydrocarbons, chemicals that may be left behind from the wetlands’ earlier stint as a major oil field, as of a couple months ago.

The few months of hydrocarbon results aren’t much to draw conclusions from, Carlberg stressed. But the numbers seem low so far, he said.

“Next year we might have you back here for a conference on hydrocarbons,” he said.