CCW supplies water for municipal and industrial use in a seven-county service area covering 140 square miles. From the west of Corpus Christi, water is drawn from the Lake Corpus Christi and Choke Canyon Reservoir System, both within the Nueces River Basin, and sent to the O.N. Stevens Water Treatment Plant. To the east of Corpus Christi, water is transferred from the Colorado River via Mary Rhodes Pipeline Phase II and from Lake Texana via the Mary Rhodes Pipeline Phase I and sent to the O.N. Stevens Water Treatment Plant.

Model Results

Due to the ongoing drought, the City developed a model to predict the water levels in the Western Supplies (or Western Reservoir system). These results indicate when the water stored in the Western Reservoir system will run dry and the City will not be able to meet the total water demands. This model will be updated bi-weekly, or as water and weather conditions change. This dashboard was created using data through April 15, 2025. Improvement to the forecast on Western Supplies is a result of more precise accounting of water storage in the Choke Canyon Reservoir. The new measurement increased the water volume by approximately 2,500 acre-feet.

Choke Canyon Reservoir and Lake Corpus Christi are the City’s longest-established and largest water supplies. The City controls the water in both reservoirs. Both reservoirs are monitored daily and are operated per the 2001 Texas Commission on Environmental Quality (TCEQ) Agreed Order. The 2001 Agreed Order is an agreement between the State and the City that mandates that the combined reservoir storage level be used to implement drought stages. For these reasons, the City uses the combined capacity of Choke Canyon Reservoir and Lake Corpus Christi as the triggering criteria for the initiation of the drought stages as described in our Drought Contingency Plan, this also ensures the protection of our largest water supplies.

Model Inputs

• Mary Rhodes Pipeline pumping schedule 4 (70-75 MGD)
  • Assume two weeks in schedule 3 (55-58 MGD)
• Nueces River Wells phased in in 2025
  • 3 MGD by June 2025, plus 3 MGD by September, plus 3 MGD by November 2025
• Extremely low stream inflows into the Western Reservoirs, as observed in 2024. These stream inflows were the result of the 2024 rainfall amounts and are used as the input for 2025 through 2027.

Level 1 Water Emergency*

Pursuant to the 2025 approved Drought Contingency Plan, the City has adopted a new “Level 1 Water Emergency” previously known as “Stage 4”. This Level 1 Emergency is initiated when the City reaches 180-days from when the total water supply is not enough to meet the total water demand. This does not mean the City has run out of water as millions of gallons are still available from the Eastern Supplies (i.e., Lake Texana and the Colorado River).