A Special District is a local, governmental taxing entity that provides limited services to its customers and residents. Examples of water districts include municipal utility districts, water control and improvement districts, special utility districts, and river authorities.
The Texas Commission on Environmental Quality (TCEQ) is responsible for general supervision and oversight of water districts, including:
Monitoring water district activities and their compliance with state laws. Providing information to district customers, consultants, board members, and employees. Reviewing applications and petitions for appointment to district boards. Reviewing the issuance of bonds that finance certain district infrastructure.
These Special Districts assess property taxes (ad valorem taxes) and pass bonds to pay for infrastructure facilities (through direct construction or reimbursements), and operation and maintenance of certain District facilities, as defined by TCEQ for each individual District.  These facilities can include, but are not limited to, water infrastructure, wastewater infrastructure, storm water quality and detention facilities (ponds), open space areas, and roadways.
Each individual Special District has its own unique rules and regulations, including governance structures.  More information can be obtained by visiting TCEQ’s website at https://www.tceq.texas.gov/waterdistricts/districts.html