Drain flies

[Rod]

My mother's 1960s bungalow is suffering from drain flies, also known as filter flies, moth flies or various species of Psychoda. (Actually, it is her who is suffering rather than the bungalow!)

Last year she had some though they slowly disappeared. She has just had hundreds start to fill her kitchen and bathroom and it sounds much worse than last year. There is no obvious source but, from published information, it seems that they like sewage and other organic substances, moisture and warmth. So I guess the warmer weather is setting them off again.

One possibility seems to be that the main drain is cracked or broken, either under the bathroom floor, as it goes through the wall (underground) or where a wachine machine drain joins it (just outside the wall, again underground). However, I don't see quite how the flies are getting from there into the house. There is no obvious problem indoors except the presence of the flies.

What I am looking for is some advice:

How can you identify where the flies are coming from?

Is there such a thing as a professional drain engineer who could be employed to identify the source and recommend treatment?

Are there any useful 'pour down the drain' products?

Can you buy dyes that could be used to help in identifying leaking drains?

Is there any way of reparing a broken/cracked drain short of digging?

Anything else that might help! She is feeling somewhat desperate about this as it affects cooking, cleaning and even making a cup of tea.

[Owain]

Drain rodding / CCTV may reveal a fault, as might dowsing.

Jeyes fluid (disinfectant), or caustic soda may remove partial blockages where sewage is accumulating

Yes; try hire shops that hire drain rods. Or food colouring.

Not really. Big drains can be lined with a plastic liner but I don't think this can be done with individual house drains.

Council Environmental Health may be able to help. This may be a pest problem rather than a drain problem.

Owain

[Phil Anthropist]

One source of advice is the pest control officer at your local council. There must be stagnant water somewhere. If it was an older dwelling with floorboards in the downstairs rooms then it is possible that there is flooding under the floor from a blocked or leaking drain, but I guess that a

1960s bungalow has concrete floors downstairs. Drains can be relined without digging them out.

[Rod]

"Phil Anthropist" wrote in news:445618d8@212.67.96.135:

The council pest control man has been round several times but has not yet managed to identify where the problem lies. That is why I am really getting involved (rather than just supporting).

Absolutely - concrete floors throughout.

Thanks for the response.

[Dave Fawthrop]

|"Phil Anthropist" wrote in |news:445618d8@212.67.96.135: | | |> |> One source of advice is the pest control officer at your local |> council. There must be stagnant water somewhere. If it was an older |> dwelling with floorboards in the downstairs rooms then it is possible |> that there is flooding under the floor from a blocked or leaking |> drain, but I guess that a 1960s bungalow has concrete floors |> downstairs. Drains can be relined without digging them out. | |The council pest control man has been round several times but has not |yet managed to identify where the problem lies. That is why I am really |getting involved (rather than just supporting).

The Ultra Violet Fluorescent, High Voltage fly killers, are available from shopfitters, and commercial kitchen suppliers, work quite well at killing flies. But get a *good* one.

[meow2222]

there must be something they like. I take it all food is stored securely, in closed containers, she hasnt killed and buried anyone there, drains arent blocked, gross habits of some weird kind are not occurring, and every last trace of garbage has been cleared out. If so, I'd:

2 look for any inacessible spaces where a small animal might have died. 1 Get a vapona flykilling vapour thing in there 3 maybe get an electric flykiiler - but it needs to be a proper one, the =A35/=A310 jobs are no use. 4 observe to see if there is some location where the flies all come or go, maybe a hole somewhere

She's not by any chance a Hitchcock fan?

this is not unusual with very old drains, but doesnt cause this problem.

If she can breathe, some flies can get in, and can breed on site.

just observation.

I'm doubtful it would be a drain issue. Open drains are normal, but dont cause these problems. Minor foul drain leakage ditto, major foul drain leakage and you'd have no difficulty finding the problem with your nose.

caustic soda or washing soda and boiling water. But if the drain isnt blocked, I'm not convinced these will be useful.

fluorescein dye, available from plumbers merchants, screwfix etc, but

27p food dye is far cheaper, and assorted colours mean you can tell which place your coloured outflow came from.

yes, but IME digging was cheaper.

Well, =A36 spent on a couple of vapona slow release strips should clear the place of flies and relieve the desperation. If theyre still there a day later (unlikely), you can always chemical bomb the place for instant knockdown. Then youve got 1000 dead flies to clear up.

Dont overlook the hoover bag, could be something wet or damp in it. Really its just a case of going through the property in great detail, removing anything damp enough for flies to eat. I'd also check the loft, loo cistern, under loose floorboards, under and inside the washing machine, mattresses, everything and everywhere. I cant help but distantly wonder if there might be something she's not telling.

NT

PS Sounds like a great opportunity to make Garibaldi biscuits.

[Rod]

For Mary (and anyone else interested):

Can you dowse for drain flies?

[Mary Fisher]

I think you can dowse for anything!

Mary

[Mary Fisher]

I wish I hadn't asked :-(

Mary

[Chris Bacon]

Get rid of flies currently in the room. Close the doors and windows. Spend an hour or two in there looking for entrances.

[Rod]

Rod wrote in news:Xns97B691368887Dgsdfgre@130.133.1.4:

Thanks for all the responses.

I shall be going over at the weekend and trying to see what I can do. Should have various things to play with by then.

[Rod]

[e-mail] wrote in news: [e-mail]:

Well, I spent a thoroughly enjoyable day mucking out drains. The drain from the house to the main street sewer had a surprising amount of stony muck in it. Despite that, there was clearance all the way through so it was not stopping the flow. Anway, rodded that through and cleaned it all thoroughly. Looks good enough to eat dinner off....

The short run from the stack to the inspection cover had a few bits of stone in it. Having cleared what I could, it still had a ghastly graunchy sound when I tried to rod it. The stack pipe is cast iron. The drain pipe is salt glazed. The only way that noise could happen is if there is something mighty wrong.

Let out near enough a full bath, flushed the WC, but very little water coming through the drain. There simply must be some sort of void under the floor, round the base of the stack pipe. This void must fill when liquid descends the stack pipe and slowly soak away. The clearing (as above) has increased the amount of water that comes down the drain but is still not as much as is flowing down the stack pipe. And I'd guess that at least some of the stone found comes from around the base of the stack/start of the drain.

Time to get someone who knows how to dig out underground drains.

Thanks for all contributions.

[meow2222]

Sounds like you've found the source of the problem.

just dig down t them from ground level, if anythings come apart or broken up you'll see it. Its only a pipe after all. I get the feeling you'll expose a royal stench though.

Drain pipes are a fairly low tech thing, you should be able to dig and fix it no problem. Well, apart from gagging.

NT

[Chris Bacon]

That sounds like a good plan, you've done most of the work by isolating the problem area.

[Dave Fawthrop]

|meow2222 wrote: |> Rod wrote: |>>Time to get someone who knows how to dig out underground drains. |> |> just dig down t them from ground level, if anythings come apart or |> broken up you'll see it. Its only a pipe after all. | | |That sounds like a good plan, you've done most of the work |by isolating the problem area.

Using a spade and *not* a pickaxe would be a good idea

[Rod]

Dave Fawthrop wrote in news: [e-mail]:

Unfortunately:

The last metre of drain (from under the house wall to the inspection pit), which would easily be diggable, is clear as a bell;

The location of the problem is under the (concrete) bathroom floor - not outside;

There is no other drain in the house, hence, while out of action, so too is the WC and all other drainage;

I am back home (many miles away) now!