RICHLAND -- Dozens of dead fish floating belly-up at the pond in Richland's Badger Mountain Village during the weekend prompted resident Mike Neely to alert the Kennewick Irrigation District.
The fish kill, which KID officials said was unintentional, might have been the result of a copper-based herbicide used to kill off aquatic plants and algae that can clog irrigation systems. Or it might have been caused by a warm-weather bloom of algae in the pond.
Neely told the Herald he was shocked to see at least three dozen large carp and hundreds of goldfish had died.
Neely sent an email to KID on Saturday, concerned after he and his young granddaughter made the discovery.
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"It was very, very sad when I took my 3-year-old granddaughter to the pond ... to feed the fish and she saw all the dead fish. She was very upset," Neely wrote.
Chuck Freeman, KID district manager, said the pond has received several copper treatments, but the fish kill also might have been caused by oxygen deprivation. He said hot weather can trigger algae to bloom, and algae consumes the oxygen in the water.
"That is an irrigation pond and is not supposed to have fish in it," Freeman added.
He said KID's practice of treating irrigation water to control aquatic weeds is done according to established policy and permits.
"Nothing was done out of the ordinary," he said.
The pond serves irrigation water to KID customers in the Badger Mountain Village area, Freeman said.
"Somebody planted them, and now we are having to spend taxpayer money to go out there and clean up dead fish," Freeman said.
KID plans to introduce more weed killer into the pond next week. That product, Endothall, is specifically to target algae growth.
Neely said Freeman told him no one had informed KID there were fish in the pond.
"I guess we won't be feeding the fish there anymore," Neely said.