The year 2021 began with a status of Stage II Drought as below-average rainfall during the summer of 2020 wasn’t enough to keep levels from declining towards Stage II Drought thresholds. By early October 2020, Barton Springs and Lovelady crossed under their Stage II Drought thresholds and the BSEACD Board declared an Alarm Stage II Drought on October 8. Levels declined throughout the fall and winter as La Niña conditions - beginning in July 2020 - brought warmer and drier climate to the Hill Country leading into 2021.
Rainfall in 2021 began with a combined 3.5 inches of rain from January to March (3 inches below historical average), perpetuating the downward spring flow and water level trend. While some relief came with over 3 inches of rainfall in April, little recharge was seen as the dry soils soaked most of it up. The increased soil moisture from April rain set the stage for 8 inches of rain in May to generate enough recharge to reverse the downward spring flow and water level trends. The Climate Prediction Center (CPC) officially declared the end of La Niña in May 2021, beginning an ENSO-neutral (neither La Niña or El Niño) period that allowed for above average mid-spring and summer rainfall totals of 20.4 inches. Barton Springs and Lovelady water levels began to rise on May 1st for the first time since July 2020.
A combined 15 inches of spring rain fell March - June 2021, providing enough recharge to overcome the dry La Niña winter and reverse the falling spring flow and aquifer trend. With both Barton Springs and Lovelady water levels rising above their respective Alarm Stage II Drought thresholds, the BSEACD Board declared “No Drought conditions'' on July 8, 2021. An additional 7 inches fell in July and August. On August 25, Lovelady water levels began to decline, looking as if the No Drought period would be short-lived. The CPC officially declared the return of La Niña on October 14, 2021, which, oddly coincided with up to 6 inches of rainfall in the Hill Country the day before. This brought considerable recharge as stream gauges on all area creeks showed rises. Spring flow and water levels showed a rising response.
To summarize, the Austin/Hill Country area has received an average 36.4 inches of rainfall so far in 2021 (through December 7th), about 1 inch above the annual average, which means we will finish 2021with an above-average year. This may be due to the 6-month ENSO-Neutral period from March to October 14, 2021. While this might have allowed us to pass the 35.5 annual average, La Niña has officially developed again and is expected to continue into 2022. This could bring drier and milder-than-normal conditions across Central Texas, which will likely result in further declines as 2022 gets underway. Hopefully, spring of 2022 will bring its usual upward swing of recharge to keep the aquifers well-supplied.
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