Water quality monitoring to resume at Jacob’s Well

Under a new agreement with Hays County, water quality monitoring at Jacob’s Well will resume. Water quality monitoring at Jacob’s Well stopped last year as funding ran out.

The iconic Hill Country swimming Cave near Wimberley voted last week to grant $34,500 to monitor it continuously through September 2025.

From 2005 to 2023, the USGS collected water temperature data; Turbidity, the number of particles in the water; And specific conductance, a measurement that can indicate contamination by tracking levels of compounds in water.

Commissioner Lon Shell said the federal agency informed the county that funding for the project would not be renewed, and oversight ended last year.

Shell told commissioners that spring “has been in jeopardy for several years,” so it was important to continue collecting data. They voted unanimously to approve the appropriation. Under the agreement, USGS will contribute $32,800 to the project through next October.

A new sensor will also be added to monitor nitrate levels; This nutrient can cause algal blooms and other water quality problems.

Jacob’s Well comes from the Trinity Aquifer, a complex groundwater formation that sits over much of Central Texas and is an important source of drinking water. While this spring is known for its popular swimming destination, experts say it is also an indicator of the health of aquifers. Under typical conditions, it releases thousands of gallons of water per day and is kept at a constant temperature of 68 degrees.

The spring has been off-limits to swimming since 2022 due to low water levels, and last year it stopped flowing completely from late June to October.

In a document outlining the monitoring plan, the USGS called Jacob’s Well “an important artesian spring that has a significant impact on the overall health of the watershed.”

“Jacob’s Well is vulnerable to constant stress from heavy groundwater use, expanding development and frequent droughts,” the agency said, adding that real-time continuous data will provide information on the health of groundwater in the Trinity Aquifer and Cypress Creek.