Guadalupe Estuary | Major Estuaries | Texas Water Development Board

Guadalupe Estuary (San Antonio Bay)

The Guadalupe Estuary is located on the mid-Texas coast and includes San Antonio Bay, Mission Lake, Hynes Bay, Espiritu Santo Bay and Mesquite Bay.  This estuary is largely protected from the Gulf of Mexico by Matagorda Island, and typically does not have a direct connection to the Gulf except through Cedar Bayou when it is occasionally opened by tropical storms.  The other closest connection with the Gulf of Mexico is through Pass Cavallo, to the northeast, in the Colorado-Lavaca Estuary.  The Guadalupe Estuary typically receives an average of 2.5 million acre-feet of freshwater inflow per year from its major contributing rivers, the Guadalupe and San Antonio Rivers, as well as runoff from surrounding coastal watersheds.  The estuary lies adjacent to three counties, including Aransas, Refugio, and Calhoun, and is affected by the activities of the Region L (South Central) Water Planning Group.

Selected Guadalupe Estuary Studies

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