It doesn't matter how water or flooding enters, the real question is what to do after a flood.  Homeowners in Aurora have flooding from rain storms, plugged drains, failed footer drains, failed sump pump, and broken pipes.  So, the first task is always to stop the water and get rid of the water as fast as possible.  This is were a wet vacuum can be helpful after the bulk of the water is pumped out.

It takes mold about 48-96 hours to start when conditions are wet, so the quicker things are dried out, the less problem there will be with mold and mildew.

In addition, get rid of cardboard, paper, and wood in the basement.  These are the food for mold.  Mold loves cellulose material and wet or damp conditions.  Deny mold the essentials of life, and you won't have serious problems.

However, I strongly recommend a spray treatment of Decon Five after the water is done and things are cleared out.  Decon Five is an EPA registered and non-toxic spray system that kills mold and mildew on contact.  And, it neutralizes mold spores.  The process is simple and effective.  Typical treatments from $250 to $400 depending on size, conditions, and level of threat.