Alva Review-Courier -

McALLEN, Texas (AP) — On a scorching afternoon in South Texas, Sonia Lambert looked out at an open-air canal that carries mud-green water from the Rio Grande to nearby towns and farmland, losing much of it to evaporation and seepage along the way.

"That will be someone else's problem," Lambert said, referring to her upcoming retirement as head of an irrigation district near the U.S.-Mexico border.

In the Rio Grande Valley, a canal system designed more than a century ago for agriculture still delivers water to the region's lush farmland and fast-growing towns and cities. Today, the canals lose...