From: Hendrickson, 2001
The Brazos River begins in eastern Stonewall County, Texas, and extends along a winding trail over 1448 km to the Gulf of Mexico. A number of tributary rivers (e.g., Clear Fork, Bosque, Lampasas, Leon, Little River, Navasota) contribute additional water to the flow of the Brazos. The Brazos River watershed reaches into eastern New Mexico and extends in a southeasterly arc through Texas to the Gulf of Mexico near Freeport. In Texas, the basin covers more than 108,800 sq. km, about one-sixth the total area of the State, and encompasses 65 counties containing a population of over 2 million. It is the longest river in Texas and freshwater discharge to the Gulf is approximately 6,784 million cubic meters per year (Hendrickson, 2001). At its terminal end, the river mixes with tidal water from the Gulf of Mexico forming the Brazos River estuary.
The river has been dammed in several places to form reservoirs for flood control, municipal use and recreation. Important man-made lakes on the river are the Possum Kingdom and Whitney reservoir.