UPDATE: Concerning Boil Water Advisory From Hays County

Immediately following the May 24, 2015 floods, Hays County issued a boil water advisory so that citizens would be aware that there may be some issues regarding the safety of their well water. Though not defined at the time, private well systems inundated by flood waters were of particular concern. Hays County has performed a series of water samples from citizens volunteering their wells as sample locations. Those results will be made available as they arrive.

Private well owners are not governed by the drinking water standards that public water supply systems have to follow; ultimately it is up to each individual landowner to determine how and when to treat their own private well water.  Well owners may have experienced a change in taste, smell, or appearance associated with the significant flooding event.
Well decontamination procedures

Although the county is lifting the boil water advisory, citizens who are concerned about the drinkability of their well water are encouraged to take steps to test or disinfect their water to limit problems with bacteria.  The complexity of our local groundwater sources makes a widespread determination of safety an impossibility.

To check whether your well is contaminated with surface run off you can submit a sample for testing to the Edwards Aquifer Research and Data Center in the Aquatic Biology building, on Sessom Drive, across from Salt Grass Steak House in San Marcos. You can obtain a sample container and directions to sample. Bring your sample back with the appropriate fee (+-$20) and the sample will be tested for coliform within 24-48 hours. The phone number is 512-245-2329.

If you work in Austin you can take the sample to the Lab at LCRA or the TX Department of State Health Services.