What's that in the pool? Oh, just thousands and thousands of insects that keep coming back

A month has passed since a swarm of insects bombarded the Coachella Valley and swimming pool owners still haven't been able to get rid of the unwanted guests that are costing them hundreds of dollars to cleanup.

Layers and layers of boatmen bugs, which pounded the desert Nov. 6, are still showing up in residential pools from one end of the valley to the other. And every time one batch is removed, another tends to arrive and cause headaches for property owners.

"They stink to high hell. I literally at times have had them by the millions,” said La Quinta resident Ed Kulyeshie, 69, who estimates he spent about $500 on chemicals to remove the insects and another $1,000 on draining his pool. "At their worst, they’re filthy. Like the top of my pool was black.”

Experts say anyone who wants to rid their pools of the bugs has two specific options: Treat pools with algaecide or wait for the bugs to go away.

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The insects aren't harmful or invasive to the community, and the popular opinion among experts is that they came from the Salton Sea. The bugs typically grow up to 8 millimeters, feed on algae and are most active during the summer.

The biggest mystery is still why they suddenly appeared in huge numbers last month and filled swimming pools and covered car roofs across the desert.

"They’re native insects and it’s just an unusual number of them that’s happening,” said Doug Yanega, University of Calfornia - Riverside's senior museum scientist in its Entomology Research Museum.

Boatmen bugs can fly several miles and Yanega surmised strong winds may have pushed them into the community. But according to the National Weather Service, winds out of the east peaked at 15 mph on Nov. 6 and that's hardly abnormal.

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City streets are mostly void of the insects nowadays and swimming pools appear to be the best place to find them.

Spokespeople from several major hotels say they're not affected by the insects and tourists should be able to use their pools. Yanega said that's likely because boatmen bugs feed on algae and are turned away by hotel pools' high sterility.

Cindy Clark, who co-owns The Pool Store in La Quinta, said pool owners from across the desert have been calling "every hour" seeking assistance in removing the bugs. She's encouraging city officials to find solutions to the pest problem.

Coachella Valley Pest Control owner Craig Conaway said it's not the first time boatmen bugs have appeared in the desert and he reiterated the large numbers is what makes the recent swarm unusual.

Conaway suggests local residents be patient, since the boatmen bugs should eventually go away.

"It’s just going to be a situation where it has to die out,” he said.