Recent rains have added much-needed recharge to the Trinity Aquifer in western Hays County. The Edwards Aquifer Authority weather station on the Blanco River upstream of Wimberley measured over 8 inches of rain in September alone. The rainfall initially generated considerable runoff and temporarily increased flow in both the Blanco River and Cypress Creek. Soils absorbed a lot of the rainfall and shallow soil moisture levels have increased. Smaller creeks and tributaries responded during the rain event but stopped flowing shortly after the rainfall. Springflow at Middle Trinity springs (such as Jacob’s Well, Pleasant Valley Springs, and Park Springs) increased after the rains, but have begun declining since no additional recharge is making its way into the groundwater system. [Read more on water monitoring in the September Hydro Report.]
The Hays Trinity GCD has taken steps to safeguard the groundwater supply and protect springflow. At their September Board meeting the Board voted to increase the drought stages effective for September.
From the September 11, 2020 HTGCD Press Release:
Effective September 1, the Hays Trinity Groundwater Conservation District Board of Directors voted to move the Jacobs Well Groundwater Management Zone into 30% Curtailment and the rest of the District into 20% Curtailment drought status.
The curtailments will help prolong groundwater availability for all users. Permittees are required to reduce usage to extend supplies until the area receives enough rainfall to sufficiently recharge the aquifer. Groundwater users—whether served by a water utility or well–should reduce water use, which is usually achieved by limiting outdoor water use.
“The full heat of summer is upon us!” said Linda Kaye Rogers, HTGCD Board President “It is critical that we all conserve where we can by cutting back on outdoor usage.”
The Hays Trinity Groundwater Conservation District reports that District-wide, wells are experiencing sharply declining water levels. District and volunteer citizen monitor wells are down from June and 10 percent below levels seen last August. District monitor wells in the northwestern quarter of the District are at their lowest levels on record.
“Local well drillers are reporting an increase of dry-wells,” said District General Manager Charlie Flatten “they are recommending limiting unnecessary pumping to protect your pump from burning out.”
Jacobs Well spring flow is the District’s trigger for drought curtailment in the JWGMZ because it is an indicator of groundwater storage within the zone. 30% Curtailment is called for if flow drops below a 10-day average of three cubic feet per second (CFS) as measured by the US Geologic Survey (USGS) flow gauge at the spring. Average spring flow exceeding 6-CFS over a 10-day period will bring the JWGMZ out of drought curtailment.
The immediate rainfall forecast shows no major rain events in the near future. The National Oceanic and Atmospheric Administration (NOAA) predicts very little rainfall and higher than average temperatures through the rest of the summer.
The Texas Water Development Board recognizes that Hays County and much of Central and West Texas continues to experience Extreme drought conditions. Many residents in the District are already under conservation restrictions. Please visit the Hays Trinity Groundwater Conservation District website for more drought information and tips on conservation at home.