Rio Grande Valley residents could lose some of our most unique natural areas to the border wall before most of us have even had the opportunity to experience them.

According to the documents Customs and Border Protection (CBP) has released as part of their request for public input, they plan to build a 20- to 30-foot-tall bollard border wall, together with a 150-foot cleared enforcement zone and patrol road, running almost the entire length of Starr County.

Clearly these walls will be a blight upon towns like La Grulla, Rio Grande City, and Roma, requiring the condemnation of homes and businesses, subjecting neighborhoods to increased risk of flooding where border walls cross drainages, and marring the towns’ historic charm with their ugly and forbidding presence.

But walls built outside the County’s population centers would be destructive as well and could lead to the permanent loss of natural treasures that few people even know exist. Walls could also completely cut off our access to the Rio Grande as it flows through this ruggedly beautiful region.

CBP has already awarded a border wall construction contract for the Arroyo Ramirez and Las Ruinas tracts of the Lower Rio Grande Valley National Wildlife Refuge west of Roma.

Arroyo Ramirez is laced with astonishing gray and white reefs—the fossilized remains of ancient oyster beds. The beds are made of the shells of an extinct species of giant oyster that thrived in the shallow sea of the Eocene Epoch, 55 to 36 million years ago, when the Gulf coastline was further to the west. Erosion from water flowing into the Rio Grande (the river is far younger than the fossil beds—only about a million years old) has removed the layers of clay that once covered the fossils. The slabs are now exposed in the Arroyo Ramirez and other Starr County drainages, their mother-of-pearl still flashing rainbows in the sun.

Arroyo Ramirez is also critical habitat for the Zapata bladderpod, an endangered plant which grows only on the sandstone of the rugged hills in Starr and Zapata counties. This plant in the mustard family is specially adapted to the arid conditions of the western Valley. Remarkably, it remains dormant and essentially undetectable until there is enough moisture to grow, bloom, and fruit, which it does, and then disappears under the soil again.

Building a wall across refuge tracts that contain fossils and endangered plants seriously threatens them both. The footprint of the border wall itself, construction roads, and staging areas could require demolition of the oyster beds or destruction of bladderpod habitat. The plan to build the wall across drainages like the arroyo that the tract is named for will also lead to flooding, which will cause erosion and sweep away vegetation.

And while fossils and endangered species are usually protected by U.S. law, the Real ID Act waiver authority gives the Secretary of Homeland Security the power to simply ignore laws like the Endangered Species Act in order to build border walls. In fact, acting Homeland Security Secretary McAleenan has already invoked a waiver for Arroyo Ramirez and Las Ruinas, meaning that CBP can start building without concern for the damage walls will cause.

The Arroyo Ramirez flows into a beautiful Rio Grande lined with trees, bluffs, and sandstone outcroppings. The stretch of river from Falcon Dam down to Roma often astounds visitors who are only familiar with the flatter muddy delta of the lower Valley.

For paddlers like myself, the westernmost Starr County canoe or kayak put-in at the tiny community of Chapeño is the best. From here you can paddle the crystal-clear water upstream to Falcon Dam, dodging the water-sculpted sandstone boulders in the riverbed as you watch osprey diving for fish. Then you can turn and follow the white pelicans as they glide silently together downstream.

Upriver from the little town of Salineño, a remnant stand of Montezuma cypresses shades the river, their thick tangle of roots anchoring them to the banks. These water-loving giants once lined the Rio Grande, but this stand is the only one left. At the end of the river road in Salineño, families fish, kids jump off the rocks into the water, and birders comb the shore of the Salineño Preserve, looking for a glimpse of Starr County specialty birds that can be seen no where else in the United States, such as the red-billed pigeon and the white-collared seed eater.

But this experience of the Rio Grande, already all too rare, may no longer be possible when the border wall slices through Chapeño and Salineño, cutting us off from the river and the ability to access the natural world of Starr County.

By blighting the landscape, destroying those things in the natural world that inspire wonder and awe and walling us away from our river, the federal government is essentially stripping away our natural heritage. What are our communities without that?

What is the Rio Grande Valley without the Rio Grande?

Editor’s Note: Customs and Border Protection is accepting comments on their border wall plans through Monday, August 26.Submit your comment here.

Editor’s Note: The main image accompanying the above guest column shows the author on the Rio Grande upstream from Roma, Texas. Photo credit: Scott Nicol.