Private water wells should be tested annually. The Blanco County Office of the Texas AgriLife Extension Service is sponsoring a water will screening day for area residents on April 18, 2011, at the following location: The AgriLife Extension Office, in Johnson City. We are now located at 101 East Cypress, Suite 109 (in the Annex Building just north of the Blanco County Courthouse).

Samples from private water wells will be screened for possible contamination from common contaminants including fecal coliform bacteria, nitrates, and high salinity. The cost is $6.00 per sample.

The presence of fecal coliform bacteria in water indicates that feces (bodily waste from humans or animals) may have contaminated the water. Water contaminated with fecal coliform bacteria is more likely to also have pathogens present that can cause diarrhea, cramps, nausea, or other symptoms.

Water with nitrates at levels of 10 parts per million (ppm) is considered unsafe for human consumption. Nitrate levels above 10 ppm can disrupt the blood’s ability to carry oxygen throughout the body, resulting in a condition called methemoglobinemia. Infants less than 6 months of age and young livestock are most susceptible.

Salinity as measured by Total Dissolved Solids (TDS) will also be determined for each sample. Water with high TDS levels may leave deposits and have a salty taste. Additionally, using water with high TDS for irrigation may damage the soil or plants.

You will need to pick up a sample bag and instructions from the Blanco County AgriLife Extension Office. You can contact the Extension Office by calling 830-868-7167 to receive an approved water sampling bag and instructions for taking your well water sample. It is very important that only sampling bags from the Blanco County Extension Office be used and all instructions for proper sampling followed to endure accurate results.

A meeting explaining screening results will be held on April 19, at the Kendalia Library. It is extremely important to be at this meeting to receive your results, learn corrective measures for identified problems, and to improve your understanding of private well management.