Recharge! (May Hydro Report)

Welcome rains have saturated soils and allowed runoff.  That runoff has translated into recharge as water makes its way through karst features like caves and sinkholes into the groundwater system.  Once the recharge creeks start flowing, recharge reaches the aquifers quickly with little filtration.

The graph above shows flow at two Middle Trinity springs–Jacob’s Well and Pleasant Valley.  These springs provide the baseflow for Cypress Creek and the Blanco River in western Hays County, respectively. The 3-4″ rainfall totals at the beginning of the May contributed good recharge to the groundwater system.  Jacob’s Well flow momentarily peaked at about 30 cfs, Pleasant Valley and Park Springs temporarily reached 17 cfs. Spring flow has slightly increased even after the rainfall ended, which indicates that recharge added water to the groundwater system. We’ll see a similar response to the hydrographs with the next round of rain.  The water level in the Mt. Baldy Monitor Well has leveled off, and with additional recharge may begin to increase.

NOAA has forecast significant rainfall for late May.  Additional rains this week are expected to generate a lot more runoff, and therefore, more recharge.  With runoff comes the potential for high water in area creeks and rivers.  Be cautious when driving over low water crossings–check for water over the road.  Turn around, don’t drown.

No matter what area agencies call their drought declaration, it’s obvious water levels and spring flows remain low. In order to preserve groundwater availability, coordinated water conservation measures are essential.

[Updated 5/18/2021]

For updates, useful links, and archived Hydro Reports, visit the WVWA Water Monitoring page.