Recharge to Discharge Karst Tour – Coleman’s Canyon to Jacob’s Well

UT Jackson School of Geosciences Hydro Field Camp visited staff at the WVWA Coleman’s Canyon Preserve with Edwards Aquifer Authority (EAA) and Hays Trinity Groundwater Conservation District on May 19, 2021.

The students saw the EAA Geophysical Logging truck in action, discussed the layers of rock that intersected by the monitor well (hint: the same as Jacob’s Well), and got a look at the water table with the downhole camera. They saw karst features (caves and sinkholes) that help funnel runoff down into the groundwater system (recharge). And they hiked to Jacob’s Well to see the spring (discharge), learn how the UGSS flow gauge works, and how it serves as an indicator for groundwater conditions. It was a beautiful field day focused on science.

Edwards Aquifer Authority geophysical logging truck.
Water level measurements in wells are tricky. A student takes his first-ever measurement with an eline.
The total depth (TD) of the well is 220', the depth to water (DTW) was 132.25', and the height of the measurement point (MP) was 0.75'.
EAA staff lowered a downhole camera to show rock layers, voids, and the water surface in the well.
Students visited the WVWA Office and hiked to see Jacob's Well Spring.
Spring water is clear in contrast to runoff generated from recent rains in Cypress Creek.
Jacob's Well cave intersects the same rock layers as nearby wells. The majority of the cave passage is in the Cow Creek formation.
The USGS gauge uses a stage-discharge relationship to estimate flow based on how high the water level is.