Which of the following is a function of the TCEQ in relation to wastewater?

The Texas Commission on Environmental Quality (TCEQ) plays a crucial role in maintaining and protecting the quality of the state's water resources, which directly includes overseeing wastewater management. This function involves developing regulations, monitoring water quality, and ensuring that wastewater discharge meets established standards to protect public health and the environment. The TCEQ also provides guidance and support to municipalities and industries to help them maintain compliance with water quality regulations.

While designing treatment plants, enforcing air quality standards, and providing funding for projects are important activities related to environmental management, they fall outside the specific scope of the TCEQ's primary responsibilities regarding wastewater. Designing treatment plants is typically done by engineers and operators, while air quality standards pertain to atmospheric pollutants rather than wastewater. Additionally, funding can come from various sources, including federal programs and grants, but is not a direct function of the TCEQ itself. Thus, the function of maintaining state water quality appropriately highlights the TCEQ's central responsibility in wastewater management.