Short answer: Ants come to a Riverside pool for water, and the ones you see are almost always Argentine ants trailing from a nest under the pavers, the coping, or the lawn edge. Chlorine kills the ants that fall in and does nothing to the colony. Flying ants in the pool are a different event: winged swarmers from a nearby nest, usually after a hot day or a rain. Ending the trail means treating the colony, and ants are covered under Southland’s general pest service from $60 a month.
The pool is the largest water source in the yard, and in an Inland Empire August it may be the only one. Here is why the ants are there, why chlorine and deck sprays keep failing, and what actually stops the trail.
Why Are There Ants in My Pool?
Because it is hot and dry and the pool is wet. The UC Statewide IPM Program notes that ants enter new areas seeking food and water or refuge from dry, hot weather, and that leaky faucets and sprinkler heads attract thirsty ants. A pool is a sprinkler head the size of a driveway.
In Riverside the ant is the Argentine ant, which UC IPM identifies as the most common ant in and around California homes. Argentine colonies nest shallow, just under the soil surface, and in dry conditions they move deeper or toward moisture. Under a pool deck is both. The pavers hold shade, the sand bed holds damp, and the coping is three feet from open water.
Under the pavers
The sand base under a paver deck is a nest site. Ants push it up between the joints, which is the sandy grit you sweep off the deck.
Along the coping
The gap between coping and deck runs the whole pool. It is a highway to the waterline.
The lawn edge
Irrigated turf against the deck keeps the soil damp enough to nest in through a drought summer.
The equipment pad
Pumps and filters leak, and the warm concrete pad is a favorite nest spot in cooler months.
Will Chlorine Kill Ants?
It kills the ones that fall in. It does nothing to the nest. An Argentine colony in Riverside is a network of connected nests with many queens, and UC IPM describes their colonies as linked into one large supercolony. The hundred ants floating in the skimmer are a rounding error to that colony. Tomorrow’s trail will be the same length.
The same is true of the spray you put on the deck. UC IPM is direct that spraying around the perimeter kills only the foraging ants, not the colony or the queens, and that barrier sprays can make the situation worse. On a pool deck there is a second problem: California restricts pyrethroid sprays on hard surfaces like concrete and pavers because they run off into storm drains and waterways. Your pool deck drains to the street.
Flying Ants in the Pool
A sudden layer of winged ants on the water after a hot afternoon or a summer rain is a mating swarm, not an invasion. Ant colonies release winged males and new queens in warm weather to pair up and found new nests. They are weak fliers, they are drawn to the light reflecting off the water, and they land in it and drown. Skim them out. The event is over in a day.
Two things to check. First, that they are ants and not termites, because drywood termites also swarm on hot Riverside afternoons and a termite swarm landing in the pool means a mature colony nearby. Ants have a pinched waist and two different wing sizes. Termite wings are all the same length. Our flying ants vs. termites guide shows both. Second, if it happens more than once a week, the swarm is coming from a nest on your property, and that nest is the one to find.
Ants in the Pool After Rain
Rain floods shallow Argentine nests, and the colony moves up and out. UC IPM notes ants may appear suddenly when weather conditions change or when they are driven out by flooded conditions. After a Riverside storm the pool deck is the highest dry ground with water next to it, so the trail gets heavier for a few days, then settles when the soil drains. If it does not settle, the nest relocated under the deck.
How Do I Get Rid of Ants in My Pool?
Treat the colony, then close the routes. In that order.
Bait, do not spray. UC IPM calls baits the only insecticide recommended in most situations, because workers carry a slow-acting bait back to the nest and feed it to the queens. For Argentine ants, sweet liquid baits work year round. Southland’s ant treatment uses a non-repellent professional insecticide labeled to control multi-queen species for up to three months, plus a professional gel bait placed on active trails that keeps working for up to 90 days. Both go where the trail starts, not on the deck.
Fix the water you can. A dripping hose bib at the equipment pad, an irrigation head spraying the deck, a planter saucer by the steps. UC IPM lists leaks and overwatering as the attractant most people miss.
Pull the lawn and mulch back. UC IPM recommends keeping plants, grass, and mulch away from foundations to remove nesting sites. The same applies to the pool deck. A strip of bare gravel between turf and pavers takes away the damp edge the colony lives in.
Then keep it that way. Ants are covered under general pest service, which starts at $60 a month for homes up to 2,000 square feet and treats the perimeter, the garage, and the areas ants trail through. Active clients get a spot treatment between visits at no charge when the trail comes back. A one-time visit is $225 with a 60-day warranty. Pricing is effective 2026 and confirmed at inspection. Our Riverside ant exterminator page explains why the multi-queen colony is the reason a single treatment never holds.
End the trail where it starts
Ants are covered from $60 a month, with free spot treatments between visits. One-time visit $225, 60-day warranty.
Schedule ant service or call (951) 653-7964. Riverside and Moreno Valley offices, family owned since 2012, license PR 7461, Branch 2 and 3.
Pool Ant Questions From Riverside Homeowners
What month is ant season in Riverside?
Indoors, spring and again after the first fall rain. At the pool, July through September, when the yard dries out and the pool becomes the water source. Argentine ants are active year round here, so the trail never fully stops. It moves.
Will ants leave if I keep killing them?
No. The ants on the deck are foragers, and UC IPM notes foragers are only a small part of the colony. The queens keep producing replacements as fast as you kill them. A trail disappears when the colony is baited or the water source is gone, and the pool is not going anywhere.
Why do ants dig up the sand under my pavers?
They are nesting in it. Argentine ants nest shallow, and the sand bed under pavers is the right depth, shaded, and damp. The grit you sweep off the deck is excavated nest material. Baiting the colony stops the digging. Re-sanding without baiting gives them fresh material.
Do ants around an above-ground pool mean the same thing?
Yes, with one addition. Above-ground pools sit on a sand or gravel pad that stays damp under the liner, and Argentine ants will nest directly beneath it. If the trail runs under the pool wall, the nest is under the pool, and the treatment goes around the base.
Does Dawn dish soap really kill ants?
It kills the ones you spray, the same way chlorine does, and UC IPM notes soapy water also wipes out the scent trail they follow. That is useful for the ants on the coping today. It does not reach the nest, so use it as cleanup, not as treatment.
