How to Manage Drain Flies

Flies can be a constant problem in any home situated in a warm, humid environment. Does that sound like Florida? You bet it does. To make matters worse, any time you open your doors or window for a cool breeze or just to go outside, you invite these pests into your spaces. Garbage left out for an extended period may as well be flashing bright lights – Which also attract flies – Advertising a free meal. Drain flies, among all species of flies, can be particularly hard to get rid of.

What is a Drain Fly?

Drain flies are tiny, stout, fuzzy things. They’re somewhere around 3 millimeters long and have small, round wings that stick out to the side and make them look like blotchy little triangles. They also fly kind of funny – You might see them taking short little arcs from place to place because they prefer jumping to flying. Though adults only live for a few weeks, their eggs hatch every two days. If you do the math, you can be looking at a lot of drain flies in a short amount of time.

Despite the name, they don’t actually crawl up through your drains. They get in through tiny holes, even in closed windows. These flies spend time around drains and standing water and will actually go down into the pipes looking for meals and places to lay eggs. If you think you’ve got a drain fly problem, put some tape over your drains for a day. Then, check the sticky side of the tape. If they’re in your yard, place a cup over any open drainage sites, and check it after a few days. They’ll usually move to occupy the cup as they search for a means of escape.

Infestations can last around 20 days, and if you don’t solve the problem, they’ll reproduce and multiply rapidly.

How to Handle Drain Flies

Drain flies do best around clogged or slow-moving drains, so make sure the drains are unclogged before doing anything else. Just because they’re unclogged, that doesn’t mean they’re clean. Cleaning your drains is the next step. Get down in there with a plumber snake and remove as much decaying gunk as you can if you’ve got one. If not, take some water and add in a little bleach at a 10:1 ratio, pour it down your drain. Let it sit for a while, and then rinse down with warm water. After that, boil up some water and pour it down your drain.

You can also create a foaming cleaner with half a cup of salt, half a cup of baking soda, and a cup of distilled white vinegar in a bowl. Mix it together and pour it down your drain, then let it sit overnight. It’ll react and react, and then flush it down with hot water in the morning. If you’re competent working some pipe, pull out the U-trap and flush and clean it thoroughly before tightly fixing it back in place.

Once that’s done, try to get your hands on an enzyme cleaner. Enzyme cleaner is great because it coats your sink and helps grime pass smoother in the future. Let it sit for the instructed amount of time (it varies by cleaner!), and then rinse it with water for a few minutes. This should eliminate most of their breeding spaces. If you still notice them after a couple of weeks, you’ve got a more serious infestation – It’s time to call the professionals.