Make Sure Your Rain Barrel is Mosquito-proof!

Image Credit: CDC
Mosquito larvae

Saving water is a good thing. It should never come back to bite you.

But you know what they say about unintended consequences. So do yourself a favor. If you decided this El Niño season to buy or make a rain barrel — to conserve water, fight the drought, cut your water bills and use Mother Nature help you keep your home green — make sure it doesn’t become a place for mosquitoes to breed.

That can happen if you don’t make sure your rain barrel is properly screened to keep mosquitoes out so they can’t lay eggs inside, or if your barrel has areas on it where water pools up outside the barrel (for example, on or around the top).

Officials from the County Department of Environmental Health’s Vector Control Program said they have found poorly sealed and homemade rain barrels infested with mosquitoes. Vectors are animals — like mosquitoes — that can transmit diseases to people.

El Niño rains, which are expected to come back this weekend, have been noticeably absent in recent weeks. But Chris Conlan, a supervising vector ecologist with vector control, said that doesn’t mean your rain barrel is safe.

“When you start saving water in containers, you’ve now provided prime breeding grounds for mosquitoes,” he said, “and people forget that even if it hasn’t rained, you can still have condensation on your roof from fog and things like that, which will trickle down the gutter and fill the barrel a little.”

Mosquitoes, from our native species that can carry West Nile virus, to recently discovered invasive Aedes species like the yellow fever mosquito and Asian Tiger mosquito, only need minute amounts of water to breed and create new mosquitoes.

Getting bitten by a mosquito does not necessarily mean you’ll be exposed to illness. Mosquitoes typically are not born carrying disease. Native mosquitoes can become West Nile vectors by feeding on infected birds. And San Diego County is not home to the diseases that have been linked to Aedes mosquitoes — the Zika virus, yellow fever and chikungunya — although people who have traveled to parts of the world with those diseases have returned here.

But getting bitten by mosquitoes is always annoying.

So here are a few steps people can take to keep their rain barrels safe:

  • It’s always best to use a container that has been specifically created to be a rain barrel — as opposed to, say, a makeshift trash can — that are designed to keep bugs and debris out.
  • Use mosquito-proof screen — the same kind of mesh you can find on your window screens — to seal openings that could allow mosquitoes into your rain barrel.
  • Keep barrel lids and connectors (especially check openings where rain gutters flow into your barrel) sealed tight to keep out bugs.
  • Be sure to regularly inspect your rain barrel to get rid of any water that could pool up on the outside and create a place where mosquitoes can breed. 

For more information about mosquitoes and how to protect yourself, visit the County Department of Environmental Health’s mosquito Web page




Gig Conaughton is a communications specialist with the County of San Diego Communications Office. Contact