You will not capture a colony in your yard by "flooding" the nest or surrounding land. The water soaks through the ground too quickly. I have tried many different approaches similar to this, and none have succeeded.
Scientists collecting these colonies begin by digging up the colony on a warm spring morning when the queen is likely in the upper mound. They then place them in a 5 gallon bucket lined with baby powder or Fluon to keep the ants from crawling out, allow the ants time to reorganize, and then use a "drip method" to slowly introduce water in the bucket until the ants initiate the desired behavior. The colony is then very easy to collect in its entirety.
The simpler thing to get Solenopsis invicta started, however, is to wait for nuptial flights in the Spring and Summer, where it is easy to collect many queens. Then, simply dig up and collect brood from existing colonies. You then place the brood with the new queens, each queen in an individual test tube, which is a technique described by some as "brood boosting." The queen will care for the larvae and pupae, which will rapidly eclose into a ready workforce, and so you can easily have many instant colonies.
