Lower Colorado River Authority v. Texas Department of Water Resources

The Texas Department of Water Resources (the department) (defendant) issued a permit to the Colorado River Municipal Water District (the district) (defendant) granting the district authority to impound 500,000 acre-feet of water from the Colorado River to create a lake and use an additional 113,000 acre-feet of water annually. The Lower Colorado River Authority (LCRA) (plaintiff) challenged the permit in the district court, contending that the river was already overappropriated except during limited periods of heavy rainfall. The department and the district developed a computer model to show that the actual water use was well below the appropriative and riparian water rights, and the existing water rights cited by LCRA included no-long-used water rights that were arguably abandoned. Therefore, according to the department and the district, water was left unused and available for further appropriation. Texas law provided, among other requirements, that water permits could only issue if unappropriated water was available and the proposed new appropriation would not impair existing water and riparian rights. The district court determined that water was being left unused, which constituted available unappropriated water, despite the river being overappropriated based on certificates of adjudication, permits, certified filings, and established riparian rights during most of the year. Therefore, the district court ruled in favor of the department’s decision to issue the permit. The Court of Appeals for the Third Circuit affirmed the district court’s decision, and LCRA appealed to the Texas Supreme Court.