At first glance, it appears as if water from the Rio Grande under the Progreso International Bridge is gone. But that’s an illusion.

Water from the Rio Grande is flowing under a heavy layer of the invasive South American Water Hyacinth aquatic plant. Vegetation growing on the surface is so thick that it’s supporting objects being thrown at the water.

Those crossing the Progreso bridge expressed surprise at the sight. 

“They just think it's grass growing on the river,” Delta Lake Irrigation District Manager Troy Allen said. 

According to Allen, his district draws water from the area near the bridge, and deals with the problematic hyacinth every year.

“It'll flow through our pumps at the river, and then it ends up flowing down the canal,” Allen said. “We either manually excavate it out or we spray it with a chemical."

There appears to be cane growing on top of the hyacinth mat under the Progreso bridge. Allen said if it gets worse, they will have to take action.

“Normally the water will flow underneath it, but if it starts getting grass to grow across the top of it, the roots of the grass will impede the flow,” Allen said.

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