About 30 years ago, aboard a flight from New York to Los Angeles, I met a professor of entomology (insect studies) from USC, Berkeley who sat next to me for the 6-hour flight.
In one of our conversations, I mentioned that my friend owned a bagel store and once a month he had the exterminators in to spray for flies. But invariably the flies would be back before the next scheduled spraying.
He laughed. He said that the exterminating company was screwing my friend. That the flies were breeding indoors in some standing water. My friend should look under all the cabinets and locate the standing water and then have a plumber come and fix the leak. He should then have the exterminator come one more time and then he would be done with the flies.
It worked exactly as he predicted. The leak was located and fixed. The puddle was dried up. The exterminator came and sprayed for one last time. The flies were gone. Forever.
So when I suddenly had a major infestation of flies in my house I knew exactly what to look for (but not where to look). I had no plumbing problems.
However, I did make a home "improvement". I have a through-the-wall air conditioner that vents out to my deck area. The water that drips from the A.C. I used to collect the water with a few restaurant bussing trays. It was a nuisance, because I had to frequently empty the trays in the summer.
So, at the end of last summer, I installed a drainage tray that was designed to go under a washing machine. I hooked up the garden hose to the outlet pipe and had it drain directly into the yard. I thought I had the problem licked.
But the tray drained all but the final 1/8" of the water. That water was the source of my current problem. I added some Clorox to kill the fly larvae.
For 3 days I was using my shop vacuum to suck up literally hundreds of living and dead flies. I sprayed the window areas with flying insect spray and as of Sunday, I am only seeing 2 or 3 flies per day (plus a few dead ones). It appears that this issue will be ended in a day or two.
I still have to remove the tray, but the Clorox treatment seems to have killed the larvae. I will remove the tray this weekend. Meanwhile, it has been cool out and I have not had to run the A.C.
The moral to the story: If you have flies in the house in significant numbers, search for and eliminate any standing puddles of water
In one of our conversations, I mentioned that my friend owned a bagel store and once a month he had the exterminators in to spray for flies. But invariably the flies would be back before the next scheduled spraying.
He laughed. He said that the exterminating company was screwing my friend. That the flies were breeding indoors in some standing water. My friend should look under all the cabinets and locate the standing water and then have a plumber come and fix the leak. He should then have the exterminator come one more time and then he would be done with the flies.
It worked exactly as he predicted. The leak was located and fixed. The puddle was dried up. The exterminator came and sprayed for one last time. The flies were gone. Forever.
So when I suddenly had a major infestation of flies in my house I knew exactly what to look for (but not where to look). I had no plumbing problems.
However, I did make a home "improvement". I have a through-the-wall air conditioner that vents out to my deck area. The water that drips from the A.C. I used to collect the water with a few restaurant bussing trays. It was a nuisance, because I had to frequently empty the trays in the summer.
So, at the end of last summer, I installed a drainage tray that was designed to go under a washing machine. I hooked up the garden hose to the outlet pipe and had it drain directly into the yard. I thought I had the problem licked.
But the tray drained all but the final 1/8" of the water. That water was the source of my current problem. I added some Clorox to kill the fly larvae.
For 3 days I was using my shop vacuum to suck up literally hundreds of living and dead flies. I sprayed the window areas with flying insect spray and as of Sunday, I am only seeing 2 or 3 flies per day (plus a few dead ones). It appears that this issue will be ended in a day or two.
I still have to remove the tray, but the Clorox treatment seems to have killed the larvae. I will remove the tray this weekend. Meanwhile, it has been cool out and I have not had to run the A.C.
The moral to the story: If you have flies in the house in significant numbers, search for and eliminate any standing puddles of water
