Neal,

 

The water event you have described which comes from an outside source is categorized as a Category 2 and possibly even a Category 3 water event as referenced in the IICRC S500 Water Restoration Standard Reference Guide which is an Approved American National Standard.  Water from outside sources contain significant contamination and has the potential to cause discomfort and or sickness. Category 2 water can quickly deteriorate for many reasons which include organic and inorganic load when contact with building materials occur. Drywall that has been contaminated with this category of water should be removed and the structure should be cleaned and sanitized.