MARTINEZ — Renee Strom’s children learned to fish in the pond at Hidden Lakes Park in Martinez.
“I used to push them around there when they were in strollers,” said the 31-year-old Martinez resident. “My dogs all swam there. It’s dear to my heart. My husband fishes there four or five times a week since he retired.”
Strom has been understandably upset in recent weeks as an algae bloom sucked so much oxygen from the wooded pond that hundreds, perhaps thousands, of fish were floating dead on the water’s surface.
Tony Hicks
Strom said a fountain aerator that pumped oxygen into the water broke “months ago.” She said she has been in contact with the city and progress has been slow.
“I’ve been the Karen of the lake for a few years now,” Strom said.
City crews were out Tuesday and Wednesday cleaning up most of the dead fish. There were still signs of mortality near the shore, and not the least of which was the smell of seafood.
According to Joe Enke, a Martinez City engineer, the overgrown algae that caused the die-off was a combination of heat and the malfunctioning fountain aerator, which normally provides enough oxygen for the black bass, bluegill, rainbow trout, catfish and other fish in the lake. He said it’s difficult to estimate how many fish died — anywhere from hundreds to thousands.
“(The aerator) had a history and last spring it finally gave up the ghost,” Enke said.
The necessary parts weren’t available for a quick fix, so the city installed two new underground aerators last month. But delivery took longer than expected, Enke said.
Tony Hicks / Bay City News
He said that from what the city has seen, the biggest toll on the lake’s residents has been among the sunfish and bass. The California Department of Fish and Wildlife regularly stocks the small lake, which has enough fish to support a resident family of otters (which were not visibly present Wednesday).
The city has dealt with algae blooms in the past by chemically treating the water and using an algae harvester. The lake was sprayed earlier this year with little effect.
Sean Cochran, an environmental scientist with the state Department of Fish and Wildlife, said the department took measurements of the bloom earlier this week.
Cochran said algae and rotting vegetation around the lake build up and sink to the bottom, reducing oxygen in the water.
He said algae blooms are common this time of year, but are likely worse than normal.
“A fish kill of this magnitude has not been documented at that location, but we see it in other small urban lakes,” Cochran said. “We think this fish kill was substantial.”
Cochran said some of the hardier species, such as catfish and carp, likely survived. As for when the lake will fully recover, Cochran said, “with events like this, it’s going to take some time.”
