Nearly three months after the devastating landfall of Hurricane Harvey and the massive flooding caused by storm surge and historic rainfall amounts of over 50 inches in some areas, farmers and ranchers along the Texas and Louisiana coast are being reminded again that sea water and flood waters can present lasting risks to privately owned water wells.

While rural structures like homes, barns and shops can suffer both serious immediate and long lasting damages from high winds and deposits of silt and mud that generally can be cleaned up over a few days or weeks, other dangerous problems like mold and mildew can surface over time, presenting human health risks.

But perhaps of greater concern, another danger may lurk on your property long after the winds have gone and the floodwaters recede, especially near the coast where storm surge may have inundated property. Texas AgriLife Extension specialists are warning that risks of water well contamination is often overlooked, or in spite of initial inspection and even treatment, can still pose a major risk over time.

TEST WATER WELLS

According to the experts, water wells, water tanks and ponds on the farm or ranch can be contaminated initially by storm surge or flood waters, but the risk of contamination can also come from the slower infiltration of contaminates that filter more slowly into the water table, which can increase the chance of a delayed or secondary well contamination. The only sure method of knowing that has happened is to test or retest a well after the passage of time.

Related:Harvey was strong, but Texas is stronger

While the risk of re-contamination is low, Extension specialist warn that many rural residents failed to test their water following the hurricane, usually because they believed floodwater or storm surge may not have reached or affected their well system.

But officials with AgriLife Extension's Texas Well Network, in collaboration with Rebuild Texas, Virginia Tech and others, encourage well owners to take advantage of well water test kits if there is any question or indications that well may have been compromised.

In the Texas Coastal Bend region, especially from Nueces County and north up the coast as far as Lake Jackson, storm surge that rushed onshore at the time of Harvey's landfall presents the greatest threat of well contamination from salt water. But with over 50 inches of rain falling on a large portion of the Upper Coast and most of Southeast Texas over a six day period, contaminants could still pose a major problem for well owners.

In Victoria County, for instance, Diane Boellstorff, Texas A&M AgriLife Extension Service water resource specialist in College Station, advises rural residents that private water well owners whose wells flooded from the recent rains should assume their well water is contaminated until tested. That warning was offered after limited reports of contaminated wells surfaced long after the storm made landfall.

"You should not use water from a flooded well for drinking, cooking, making ice, brushing your teeth or even bathing until you are satisfied it is not contaminated," Boellstorff said.

She said floodwater may contain substances from upstream, such as manure, sewage from flooded septic systems or wastewater treatment plants or other contaminants. A septic system near a well also can cause contamination when the soil is flooded.

According to the Texas Well Owner Network, water well owners are independently responsible for monitoring the quality of their wells and are at a greater risk for exposure to compromised water quality.

FREE TEST KITS LIMITED

For well owners located in the Texas counties that were declared a federal disaster area following Hurricane Harvey, free test kits were available for a limited time, which has now expired. But a second round of free test kits were made available in November, but each county has specific collection deadlines. For most of those counties, the expiration dates have passed for the second round of free testing as well.

To find out the availability of free test kits in your county, check with your local Texas AgriLife Extension Agent. For those living in counties where free kits are still available, private well owners can pick up a test kit from their local AgriLife Extension office or other designated location, but must be able to return the sample to their local office from 8a.m. to 11 a.m. on the designated collection date.

A limited number of kits are available, and will be distributed as soon as possible from AgriLife Extension offices. In the event the deadline for free kits has expired in your county, ask your local Extension agent how a kit can be purchased and at what cost.

WELL WATER SAMPLING INSTRUCTIONS:

"The main goal here is to help prevent diseases associated with contaminated drinking water from harming the health of our residents in the Aransas County and surrounding areas," said San Patricio County AgriLife Extension agent Bobby McCool.

Any homeowner with a private domestic water well in the flood-affected area is eligible to have well water tested. The results will be confidential and will be either emailed or mailed to residents’ homes.

For private well owners who failed to test their water before the deadline to receive free test kits can also choose to have samples tested for microbial contamination by accredited laboratories across Texas. You can find a complete list of those laboratories, including contact information, at the following web site: https://www.tceq.texas.gov/assets/public/compliance/compliance_support/qa/txnelap_lab_list.pdf