PROJECT OVERVIEW

In May 2019, a Lake Dunlap dam spill gate failure resulted in significant changes in the Guadalupe River’s water levels and cross-sectional geometry. This impacted the portion of the river near the discharge of three of NBU’s wastewater treatment facilities. At the time, NBU had two TPDES permit applications with TCEQ that were delayed as a result of the dam failure and the change in conditions.

SERVICE DETAILS

To issue a renewal for these facilities’ Texas Pollutant Discharge Elimination System (TPDES) permits, the Texas Commission on Environmental Quality (TCEQ) required updated cross-sectional survey data and updated observations of the flow patterns for the portion of the Guadalupe River near the outfall of these facilities to validate the water quality in the river and verify the TPDES pollutant discharge limits were still being met.

Within approximately 30-days, our team surveyed 13-miles of the Guadalupe River to obtain cross-sections, stream velocities, and note flow pattern observations. A range of survey methods were used to gather this data, including GPS, bathymetric, and other conventional methods. Our team also worked alongside the Guadalupe-Blanco River Authority (GBRA) to coordinate access to the river.

Ultimately, the data collected and provided to TCEQ enabled them to verify the TPDES pollutant discharge limits were still adequate and proceed with the application process for the permits.