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UPDATE: Dead fish in Lake San Antonio possibly a result of mass suffocation, lake sets to reopen

MONTEREY COUNTY, Calif. (KION-TV) -- The County of Monterey issued a press conference on Monday providing more information regarding the large fish die-off at Lake San Antonio earlier this month.

Although the official test results came back inconclusive, according to the County, State Park officials say that the die-off was not attributed to toxins or pollution in the water that is harmful to human heath.

"Unfortunately, the test data that came back and our investigations were not able to have a conclusive result of why the die-off occurred," said County of Monterey Chief of Parks, Public Works, Facilities and Parks Department Brian Flores. "Based on satellite imagery, based on the fact that we did not have any other terrestrial or avian species die-off that were ingesting the dead fish, [we believe] an algae bloom occurred and through the natural biological process of respiration during the nighttime where the algae or cyanobacteria uses up oxygen and then as it dies off during the decomposition process also uses up oxygen, is that the fish die-off is related to low dissolved oxygen concentration in the water, essentially suffocating the fish."

Flores said that the lake is expected to re-open to the public on Wednesday, July 24. It has been closed since July 10 and testing took place over the following week, with the die-off easing on July 12, according to Flores.

MONTEREY COUNTY, Calif. (KION-TV) -- Hundreds of thousands of dead fish are mysteriously washing up on the shores of Lake San Antonio. The lake in South Monterey County is now closed for weeks as multiple agencies try to figure out what may have caused these fish deaths.

"What we are seeing today is unprecedented. We are not understanding why," said Julio Valdez from Lockwood.

The lake closure is coming out of an abundance of caution, given that officials don’t know yet if this issue is dangerous to humans. It also comes during the peak of the summer season when people are looking to cool off at the lake.

“It is a really unfortunate situation because we were having such a phenomenal year. The lake was up; thousands upon thousands of people were enjoying the lake every weekend. Our revenue numbers were through the roof. [We] nearly doubled our budgeted revenue," County of Monterey Chief of Park Bryan Flores said.

Flores adds, this year they haven’t seen any toxic algae blooms. Last year, he said those blooms were present, leading the lake to also close to human contact.

Staff are fortunately still working full hours. Flores saying they're making the most of the situation during this time.

However, nearby stores are feeling the effects.

The Playto store a few miles away from Lake San Antonio, tells me off-camera they have seen a dramatic decrease in customers since the closure.

In terms of cleanup, park officials said they’ll most likely need to hire a contractor, and the cleanup process can take multiple weeks. The county also says they expect to get those water test results early next week.

But while the economy here takes a hit, so does the ecosystem.

"It could be impacting invertebrate species, fish and wildlife. We'll be doing some gathering and some sampling, and investigation of that," said Flores.

Flores says they hope to have the test results by next week. If they can determine the die-off is not dangerous to people, the lake will reopen after the initial clean-up.

That process could take weeks.

Article Topic Follows: Monterey County
dying fish
fish deaths
lake closure
Lake San Antonio
monterey county

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Austin Castro

Reporter for KION News Channel 46.

Dania Romero

Dania Romero is an reporter at KION News Channel 46.

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