High Quality Content by WIKIPEDIA articles! The Laguna Madre is a long shallow hypersaline bay along the western coast of the Gulf of Mexico in Nueces, Kenedy, Kleberg, Willacy and Cameron counties in Texas, United States. It is separated by the roughly 20-mile (32 km) long Saltillo Flats land bridge into Upper and Lower bays. The two are joined by the Intracoastal Waterway, which has been dredged through the bay. Cumulatively, Laguna Madre is approximately 130 miles (209 km) long, the length of Padre Island. The main extensions include, Baffin Bay in Upper Laguna Madre, Red Fish Bay just below the Saltillo Flats and South Bay (Texas) near the Mexican border.