Rio Grande Valley water supply just hit an important new low.

The canals that supply water to Valley cities are supplied by the Rio Grande. The Rio Grande is supplied by two reservoirs upriver.

The combined capacity for storage for the United States has now dropped below 20 percent, which is an important number, which will trigger more water restrictions for cities.

The combined storage capacity for the Amistad and Falcon Reservoir is now at 19.71 percent, according to the latest report from the Rio Grande Watermaster. That report came out last Friday.

By law, cities in the Valley are required to have water conservation plans and within those conservation plans they have certain limits on when to trigger water restrictions.

For many of those cities, 20 percent combined capacity is an important point that will trigger new restrictions.

"As the reservoirs continue to evaporate or deplete, whichever the case might be, when we hit certain levels, new restrictions will have to go into effect. Everything, when you can water your lawn or wash your car, to how much water you can use at home without having to pay a premium for that usage," District 3 Brownsville Commissioner Roy De Los Santos said.

When water levels dropped below 25 percent late last year, it took weeks or even months for cities to implement water restrictions. 

Rio Grande Regional Water Planning Group Region M Chair Jim Darling said he hopes cities implement new water restrictions as soon as possible, and cities need to get serious about water conservation this summer.

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