Updated: Apr 17, 2025 / 06:04 PM CDT McALLEN, Texas (Border Report) — The lower section of the Rio Grande in South Texas has been named one of the most endangered rivers in the United States.

A Border Patrol agent waits for a patrol boat at the Rio Grande, Thursday, Feb. 13, 2025, in McAllen, Texas.. Water levels are low because Mexico owes the U.S. water under a 1944 international treaty.