Well water testing and salty water in the Corpus Christi area

The city tests the water in its own pipes. Testing a private well is up to the person who owns it. In the Coastal Bend, salt is the question that comes up most, but it isn't the only one.

Salt: the local issue

Salt in water is measured as total dissolved solids (TDS). The Texas Water Development Board says the Gulf Coast Aquifer's TDS is generally under 500 milligrams per liter in its central and northeastern parts, but farther south it typically runs from 1,000 to more than 10,000 milligrams per liter, and quality changes with depth and place. Corpus Christi is in that southern stretch.

For comparison, the U.S. EPA's secondary drinking water guideline for TDS is 500 milligrams per liter. That guideline is about taste, scale and staining, and it is not an enforceable limit. High-salt water can taste salty, scale pipes and heaters, and harm soil and plants if used for irrigation, a point the Texas Well Owner Network makes in its screening notices.

Whether a given TDS reading is fine for your use depends on the use: lawn, livestock, laundry or drinking. Ask the driller or a water treatment specialist once you have a number.

What a standard screening looks at

Texas A&M AgriLife Extension's Texas Well Owner Network runs well water screenings around the state and recommends testing private wells once a year. Its screenings usually cover:

• Total coliform bacteria, a general sign that something can get into the well;
• E. coli, which points to contamination from human or warm-blooded animal waste;
• Nitrate-nitrogen, where 10 parts per million is the level treated as unsafe to drink, with babies under six months and young livestock most at risk;
• Salinity, measured as TDS.

Screening events use their own sample bags and bottles, collected from the county AgriLife Extension office or a groundwater district office, and fees vary by event. For anything beyond a screening, use a lab accredited for drinking water.

Good times to test

• When a new well is finished, before you rely on it;
• every year after that;
• after a flood or storm surge reaches the wellhead;
• when taste, smell or color changes;
• before buying land or a house that runs on a well.

What the driller has to tell you

Under Texas Occupations Code §1901.301, a driller can be disciplined for failing to tell the person a well is being drilled for that injurious water has been found, that the water is a pollution hazard, and that the well must be plugged. If a new hole comes in too salty, the conversation about plugging it and trying another zone is part of the job, and it belongs in the quote.