Some water districts serving the Texas Rio Grande Valley already have warned users about possible irrigation rationing.
Some water districts serving the Texas Rio Grande Valley already have warned users about possible irrigation rationing.

It's either feast or famine for water users in the Texas Rio Grande Valley.

During 2010, Hurricane Alex drenched South Texas and northern Mexico in late June, followed by a rainy tropical depression. South Texas was in danger of Katrina-like flooding, according to a news release.

But the water spigot turned off, and 2011 was marred by a prolonged drought.

During 2011, South Texas agriculture used more than 1 million acre-feet of water compared with only 519,000 acre-feet in 2010.

Combine ag's use in 2011 with muncipal use and it totaled 1.4 million acre-feet compared with a total of 731,000 acre-feet in 2010.

Some of the 28 water districts in the Rio Grande Valley already have started warning growers that they may run short on irrigation in 2012 if demand continues to remain high.

“If growers are allocated only a few irrigations, which is about 6 to 8 inches of water, it’s important for them to start making planting decisions now,” Juan Encisco, a Texas AgriLife Research water engineer based in Weslaco said in the release. “They’ll have to decide what to plant since some crops require more water than others, and they’ll have to decide how much of their acreage they’ll plant.”

Municipal water use has priority over ag water use, too.

Most of the surface water comes from Falcon and Amistad reservoirs, which currently have about 1 million-acre feet in combined storage. That's enough for about one year without additoinal inflows from rivers in Mexico.