Farmers across the Rio Grande Valley shared their frustrations over the region’s water supply with two Republican senators. 

Senators John Cornyn and John Boozman were at a Tuesday roundtable, where farmers told them how they’ve had to downsize operations in order to stay in business.

Farmers have been struggling due to low water levels at the Amistad and Falcon reservoirs that provide water to the entire Rio Grande Valley.

As of Tuesday, the combined water totals of both reservoirs were at 19% capacity. The low water levels restrict water use for farmers.

“One of the problems though with that is the time it takes,” Little Bear Produce Producer Brett Erickson said. “The bank does not care. When it's time to pay your bill, the bank says it's time to pay your bill.”

Lawmakers are pushing for Mexico to make good on water deliveries owed through a 1944 water treaty.

RELATED STORY: Data shows Rio Grande water shortage is not just due to Mexico’s lack of water deliveries

Under the treaty, Mexico must deliver 1,750,000 acre-feet of water to the U.S. every five years. 

So far, Mexico has only delivered about a fourth of that amount. The U.S. is currently in the fourth year of that cycle.

“We are gonna use every tool in our tool box,” Cornyn said. “We have suggested withholding funds that the United States might ultimately provide to Mexico for foreign aid. That remains to be seen whether that will be necessary."

READ MORE: Appropriations bill passed by the House would withhold funds to Mexico over water deliveries