Gonzales County commissioners voted unanimously Monday, Nov. 14, to lift the ban on outdoor burning — effective immediately — that had been in place since Oct. 27.
“Due to the recent rains, the hazardous conditions have been alleviated,” a public notice by County Judge Patrick Davis states. “Citizens are cautioned to use extreme caution when burning is necessary.”
Commissioners could consider reinstating the burn ban if conditions become more untenable at a later date.
Texas A&M Forest Service (TFS), which monitors wildfire conditions for the state, uses the Keetch-Byram Drought Index (KBDI) for determination of drought conditions within the State of Texas. KBDI was developed by John L. Keetch and George Byram with the US Forest Service Southeastern Research Station to correlate the effects of drought on wildfire potential.
The KBDI is based on a daily water balance, where a drought factor is balanced with precipitation and soil moisture (assumed to have a maximum storage capacity of eight inches) and is expressed in hundredths of an inch of soil moisture depletion.
The KBDI attempts to measure the amount of precipitation necessary to return the soil to full field capacity. It is a closed system ranging from 0 to 800, where 0 represents a saturated soil, and 800 an absolutely dry soil. At any point along the scale, the KBDI value indicates the amount of precipitation it would take to bring the moisture level back to zero, or saturation.
On Monday, Nov. 14, Gonzales County had a KBDI average of 626.56, with a high of 703, especially along FM 77between Nixon and Smiley as well as at the Gonzales-DeWitt county line, and a low of 523 near the Gonzales-Caldwell-Bastrop-Fayette-Lavaca county lines. This represents a decrease of 62 points below the average of 688 reported on Oct. 24, the day commissioners voted to put on the burn ban, and a decrease of 38 points in the high and of 82 points in the low.
When the KDBI falls between 600-800, this is often associated with more severe drought with increased wildfire occurrence. Intense, deep-burning fires with extreme intensities can be expected. Live fuels can also be expected to burn actively at these levels.