The United States Environmental Protection Agency (EPA) requires all drinkng water suppliers to provide a water quality report to their customers on an annual basis. The information in t his report is based on tests conducted by the Texas Commission on Environmental Quality (TCEQ). According to the report from 2007, Fredericksburg has never violated any water quality standard. The City of Fredericksburg water system has received a "Superior Water Supply" rating from the TCEQ.
Fredericksburg's drinking water is obtained from ten (10) groundwater wells; eight are located in the Ellenberger aquifer and two are in the Hickory Sands aquifer.
TCEQ's assessment of these water sources and indicates that some of our sources are susceptible to certian contaminants (both natural and man-made). The sampling requirements for our water system are based on this susceptibility and previous years' sample data.
When drinking water meets federal standards, there may not be any health-based benefits to purchasing bottled water or point-of-use devices (filters, etc.). Drinking water, including bottled water, may reasonably be expected to contain at least small amounts of some contaminants. The presence of these contaminants does not necessarily indicate that water poses a health risk.
Rumors have long circulated that Radon is a common contaminant in our water supply. While true, the presence of Radon (a naturally occuring mineral) is due to the abundance of granite to the north of Fredericksburg.
The northern reaches of Gillespie County (as well as much of Mason and Llano counties) are home to the Enchanted Rock batholith, a huge, pink granite dome. Non-exposed portions of this enormous geological feature run throughout these Hill Country counties and are the primary source for the decomposing granite prevalent in the area. It is this granite that is a primary source of radon/radium.
Water wells in "granite country" (including two that supply the City of Fredericksburg) have been found to contain trace amounts of radium. City water from this well is mixed with water from other wells in compliance with TCEQ over site to eliminate any potentially harmful effects.
Radium is the parent element of radon. Radon is primarily associated with the Radium 226 isotope. The predominant radium found in area wells tested to date is radium 228. As radon has a half life of approx. 4 days, the simple solution to concerns on privates well is to store the water for a few days prior to use.
