Flies residing in the pipes: Drain flies

You are about to do the dishes and then in the basin you find these numerous creatures enjoying their treat over your dishes. Who are these creatures which appear suddenly and mysteriously in your basin causing a nuisance?

These are the drain flies!

Drain flies are “furry” moth-like appearing flies. They are very small: typically 2 to 5 mm in length, light grey or tan colored flies with short body and leaf shaped wings. The body and wings are covered with small hair which gives it a fuzzy appearance. Wings are too large when compared to the body; drain flies fold their wings in a characteristic roof like pattern.

There are more than 4,700 known species of these flies worldwide, most of them native to the humid tropics. Drain flies inhabit human drains and sewage systems where they are a harmless but also persistently annoying.

Drain flies lays eggs mostly in decomposing organic matter found in drains and pipes. The eggs are brown or cream in color and hatch in 32 to 48 hours. The larvae feed on the gelatinous drain matter and reach the maturity age in 9 to 14 days. Drain fly larvae are known to survive in high temperature and low oxygen conditions. Drain Flies have a life cycle of 1 to 3 weeks. Drain flies can grow quickly and hence they can multiply in a few days creating a nuisance

Drain Flies feed on waste matter within sewers and drains, they can however infest a property given the correct circumstances and no amount of fly spray will halt the infestation unless one can find their point of ingress or their food source.

The vast majority of domestic drainage systems are fairly clean in as much as they are designed to carry waste from one point to another and there should not be any waste sitting in the system, but due to defective pipe work or partial blockages this can happen providing a food source for the pests. However drainage systems are also designed so that no matter what occurs below ground these flies should not have access to your property and sinks, baths, toilets etc are fitted with water traps to prevent smells and pests from leaving the drainage system and entering your home.

So if one has an infestation of drain flies within bathroom there are usually a couple of things happening, firstly waste matter is building up either within or outside the drainage system allowing the flies to feed and breed, if this is occurring within the drainage system they are also finding an open vent out of the system and into one’s property. The life span of these pests is pretty short but they will lay eggs in your property and before long the next generation is swarming over your bathroom fixtures and fittings.

The most common and probably the most disturbing for a home owner is when one has an internal rest bend at the base of a soil vent pipe or downstairs toilet, the rest bend fractures or becomes displaced and after every flush a certain amount of water and waste escapes into the sub-floor. The matter builds up and the flies have a food source, they will then access the property above through any small gaps between floor boards or gaps local to skirting boards.

The above can also occur when small diameter waste pipes from sinks are suspended from joists in sub floors, if these pipes become disconnected or leak there is enough food stuff, grease & fat in the water for the flies to feed off.

Disused branch lines on drainage systems can often hold waste matter if the system has blocked or partially blocked at any time, because of its location below ground the waste will not dry out immediately and this can provide a steady and prolonged food source for the mites. If this disused branch line runs beneath and extension or conservatory and it have not been capped off properly the flies will find their way into the property.

Leaking and broken pipe work outside of the property can also allow the flies to enter the house, a cracked collar at the base of a soil vent pipe or a fractured gully pot that cannot maintain its water level will allow the flies to surface at ground level, if this occurs local to an air brick they have access direct into your sub-floor and wall cavity.

Restaurants and industrial kitchens can be prone to this kind of infestation due to the amount of food stuffs that can directly enter the drainage system and the worst case of infestation are seen at hospitals. This was partly due to a construction worker leaving a drain open within the building and partly due to the fact that hospital staff used the bed pan macerators for the disposal of excess food instead of using the appropriate food bins supplied.

Neighbors fighting an infestation of drain flies

September 4th, 2015, CBS46 News, Loganville, GA

Some neighbors in Gwinnett County are dealing with a pesky infestation of drain flies.

The flies, sometimes called “sewer flies,” look a lot like fruit flies. They’re basically little bugs that feast on the sludge inside pipelines and then crawl up into the sinks of unsuspecting homeowners.
“At first we thought it was fruit flies,” explained Bev Renales. Her home is one of at least a dozen in Loganville’s Fall Creek Landing subdivision that has become infested with the critters.

“They are gross. Very gross. Disgusting,” said Renales. She and her husband have hired an exterminator to treat the bugs, but they keep coming back.

“We’ve tried everything: bleach, Drano, hot water and vinegar. You name it, we’ve tried it,” said Renales.

Her neighbor, Nancy Gerber, has called the water and sewer department, but they told her there was nothing they could do to treat the lines.

“They wouldn’t even send someone out to look,” said Gerber. She’s fed up with the bugs and begun trying to trap them in a homemade solution of water, cleaning chemicals, and maple syrup.

Gerber and Renales would really like the county to come out and flush the lines because they believe this is a real health hazard.

Considering the above scenarios it becomes difficult to get rid of the drain flies once the pipes are installed. In order to prevent the flies C-Tech corporation has come up with solution – TermirepelTM .  It is highly effective against drain flies. It is cost efficient, inert, long lasting  and is stable up to 1400 deg Celsius temperature. This product manufactured by C-Tech Corporation is available in three different forms: Masterbatch, liquid concentrate and lacquer form. The pipes which are to be implanted in the drains can be incorporated with the masterbatch at the stage of manufacturing. If the pipes are already installed, the liquid concentrate and the lacquer can be applied on the external surface and on the access areas of the pipes so as to prevent the flies from entering the outside environment. TermirepelTM  is definitely a solution against drain flies.