Water Quality
Stream Segment Description
Plum Creek officially begins at FM 2770 in Hays County and flows to the San Marcos River. TCEQ has designated the stream for high aquatic life, contact recreation, general, and fish consumption uses. The stream has three water quality monitoring stations: on Plum Creek Road near Uhland and on Caldwell County Road 135 near Luling (both monitored monthly by the GBRA) and located one mile south of Caldwell County Road 202 near Lockhart (monitored quarterly by the TCEQ). These stations and a number of temporary monitoring sites are used to track the quality of water in Plum Creek.
Plum Creek was historically shallow and intermittent, running dry in times of drought and during summer but flowing after significant rainfall events. Before urban development, Plum Creek above Lockhart ran dry almost every year, and that portion of the creek was driven by rainfall and runoff. Southern reaches of Plum Creek, below Lockhart, were and continue to be fed by small springs that flow throughout the year. Due to the construction of wastewater treatment plants and their resulting discharges, Plum Creek now flows year-round over almost its entire length. USGS streamflow gages at U.S. Highway 183 near Lockhart and at Caldwell County Road 131/Biggs Road near Luling monitor streamflows in the Plum Creek Watershed.
Water Quality Assessment
Plum Creek exhibits high nutrient (nitrogen and phosphorus) concentrations and is impaired by high E. coli bacteria levels. According to the Texas 303(d) List, Plum Creek does not support contact recreation.