Barton Springs: 29 cfs
Lovelady: 468.2 ft-msl
Over the past year the aquifer has experienced multiple
drought stages. The aquifer started 2012 in Critical Stage III drought, brought
about by the most severe single-year drought in Texas history. Above average
rainfall in the winter and early spring months of 2011-2012 generated sufficient
soil moisture, runoff, and sustained creek flow to recharge the aquifer enough
for the District’s board to downgrade the Critical Stage III drought to Alarm
Stage II in February and “No Drought” conditions in March. Above average
rainfall conditions persisted until about mid-April allowing Barton Springs to
reach a peak discharge above 100 cfs. After the above-average wet conditions at
the start of the year, precipitation in May was not substantial enough to
maintain recharge conditions at former rates. Flow in creeks began to subside,
diminishing the amount of recharge entering the aquifer. The summer months in
2012 were very dry causing creeks to eventually stop flowing over the recharge
zone and aquifer levels to continue to decrease. By late August, flow in Barton
Springs had reached 69.3 cfs. Precipitation in September was scarce and a
steady decrease of aquifer levels continued. Meager rainfall in October was not
sufficient enough to overcome the soil moisture deficit incurred during the
summer and therefore unable to generate runoff or creek flow to recharge the
aquifer. Dry conditions persisted in November; the Board declared Alarm Stage
II Drought on November 15 after both official drought indicators at Barton
Springs and Lovelady monitor well passed their drought thresholds of 38 cfs and
478.4 ft-msl respectively. That alarm stage remains in effect as of January 4,
2013. The total rainfall recorded at the district for 2012 of about 35 inches
was above the yearly average for the area (33.38 inches). Despite the
above-average rainfall, it is likely the exceptional recharge deficit incurred
during the 2011 drought has prevented the aquifer from maintaining non-drought
levels.
The U.S. Seasonal Drought Outlook by the National Weather Service
indicates that drought conditions are expected to “persist or intensify” for
central Texas through January and February of 2013. According to previous
recession curves for Lovelady monitor well, if precipitation conditions remain
scarce the drought threshold for a Critical Stage III drought will likely be
passed in early March 2013.
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