Trinity River Basin Characteristics

Trinity River Description

• The Trinity River begins near the Texas-Oklahoma border in Clay, Archer, and Montague counties. 
• The Trinity River flows 512 miles, traversing five of the state's ten ecoregions, before emptying into Galveston Bay near Houston.  There are also 1,983 miles of major tributaries that drain into the Trinity.
• The Trinity River watershed encompasses 18,000 square miles (7% of state's land area), and includes all or parts of 38 Texas counties.
• Annual precipitation ranges from 36 inches at the headwaters up to 52 inches near the Gulf of Mexico.
• Many human activities affect the Trinity River, including 22 reservoirs on the river to provide drinking water and flood control.  Different land uses also affect the Trinity River, such as urbanization, commercial/industrial development, row-crop farming, livestock production, outdoor recreation and timber production.
• There are various habitats within the Trinity River watershed, including native grasslands, bottomland hardwood forests, and wetlands, though the extent of these have been reduced due to human activities.

Population Projections in the Trinity River Basin

• The Trinity River Basin is the most populated river basin in Texas with nearly 8 million people.
• The two most populated urban centers in Texas, Dallas-Fort Worth and Houston, depend on the Trinity River to meet its municipal demands.
• The population in Texas is projected to be 34-41 million people by 2030, which is twice as many people than in the year 2000.  Significant growth will occur in the Dallas-Fort Worth and Houston areas. 
• Nearly 80% of water use in the Trinity River Basin is used to meet municipal demands, and this number is expected to increase as population increases.