Downriver from the park, the landscape reverts to a band of thick mesquite and underbrush along the Rio Grande. It can feel remote, but it's just a thin buffer between the more than 600,000 residents of Reynosa, Mexico, and a master-planned community in Mission with more than 1,900 homes just a couple of miles to the north.
Across the river is a garbage dump and a Reynosa slum that reaches nearly to the bank. Smoke from burning garbage sometimes drifts across the river so thick it's difficult to see. At the river's edge, discarded pieces of clothing, orange life vests and deflated inner tubes litter the sand.
A few days earlier, as a reporter in a kayak approached a hairpin bend in the river, a cartel sentry on a bluff 20 feet above the river slammed a magazine into his assault rifle. He asked where the paddler had come from and who gave him permission to be there. A radio squawked at his waist. The cartel controls what crosses the river.
That's part of why Napoleon Garza doesn't bring his kids here to fish like he did as a child. Garza recently drove through one of the many gaps in the border wall to cut a tree stump from property owned by his uncle.
"When they built the border wall, everything ended because they left a big old gap right here that so happened to be where our land is," said Garza, 38, who sells firewood for a living. "That's where these guys have to run their dope. It's really sad."
As Garza stood above the river, two Texas game warden boats sped by, each with a rifleman scanning the shores. A few minutes later, twigs cracked and a green-clad Border Patrol agent emerged from the brush checking to see what Garza was up to — a constant occurrence near the river.
The city of McAllen, which draws its water from the Rio Grande, has pumps on a narrow strip of land between the border fence and the river. Workers there started carrying handguns after they came under fire.
The water district installed street lights, erected camera-topped towers and built a road and concrete pad so the Border Patrol could erect a mobile surveillance tower.
The district's president and general manager, Othal Brand, farmed the area for 25 years with his father. There was illegal activity then, too, and it seems likely to continue unless the Border Patrol stations agents every few hundred feet along the river, he said.
"It's like a bad neighborhood," Brand said. "You get acclimated. You don't like it, but you understand it."
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