Nueces River Water Quality Update – September 23, 2025
📍 Field Sites: Upstream of Eastern Groundwater Field & Hazel Bazemore Boat Ramp (Calallen, TX)
Field Observations (as of 12:30 PM, Sept. 23, 2025)
All wells in the Eastern Groundwater Field remain offline and are not pumping.
One well continues to have a rig on-site for maintenance.
No discharge activity observed from the cluster of six wells or Well Four.
Water Quality Readings
Field measurements using a YSI Pro30 Water Quality Meter show a difference in salinity and total dissolved solids (TDS) between two Nueces River sites. Upstream of the well field measured 0.6 ppt salinity (770 mg/L TDS), while the Hazel Bazemore Boat Ramp near Calallen showed 1.0 ppt salinity (1,287 mg/L TDS).
These results reflect natural variation in river salinity, with slightly higher readings downstream where tidal influence and regional groundwater interaction occur.
What the Data Suggests
Freshwater influence upstream: The TDS of 770 mg/L upstream from the wellfield indicates relatively fresh water conditions, likely due to recent flow releases from upstream reservoirs (as reflected in USGS gage data).
Mildly brackish water downstream: At Hazel Bazemore Park, readings show 1.0 ppt salinity and 1,287 mg/L TDS, consistent with tidal or saline mixing near the lower river.
The difference between upstream and downstream readings (~500 mg/L TDS) suggests gradual salinity increase closer to the coast — a normal but important pattern to monitor as river flow and groundwater pumping fluctuate.
Context for Nueces County
The Gulf Coast Aquifer beneath Nueces County holds both fresh and brackish zones, influenced by natural geology, salt domes, and proximity to the coast.
While these conditions aren’t immediately concerning, tracking small shifts in TDS and salinity helps ensure saltwater intrusion does not move inland over time.
The current readings, combined with confirmation that all Eastern Groundwater Field wells remain inactive, provide a valuable baseline for ongoing monitoring of surface–groundwater interactions.
In Summary
On September 23, 2025, field tests recorded 770 mg/L TDS (0.6 ppt salinity) upstream of the Eastern Groundwater Field and 1,287 mg/L TDS (1.0 ppt salinity) at Hazel Bazemore Park.
All observed wells remain offline, with no discharge into the Nueces River. These findings help track how surface salinity changes as flow conditions and operations evolve.
