SECTION 4 - Kill Airborn Flies
While you are treating the breeding grounds, it is necessary to trap and remove all flying adults as well.   This is easier than you might think.   The little buggers are alcoholics, so you can make a very effective trap with a shot of liquor. A ny dark liquor will do, but whiskeys seem to have the best success rate.  

Place the whiskey or bourbon in a short glass (rocks or lowball) and cover it with plastic wrap. T he amount depends on the diameter of the glass, but in general only a half-ounce or so is needed.   Poke one hole in the center of the plastic.   The flies will get in the glass to feed on the whiskey, but will become disoriented and not be able to fly out.   By morning you will find many flies floating in the glass.   The traps begin to lose effectiveness after a few days.   I recommend setting multiple traps and changing their location.   The bigger the problem, the more traps you will want to use.