Walls are built for a single purpose: separation. While most of the controversy over President Trump’s proposed border wall stems from the cultural and social impacts it may have on the United States and Mexico, there are also some serious environmental issues concerning its construction.
The U.S.-Mexico border encompasses six distinct environmental regions including scrub-land, forests and marshes. According to a paper published in "Bioscience," the proposed wall would split the ecosystems of 1,506 native plants and animals; 62 of which are classified as critically endangered. The paper argued further that walls would increase soil erosion and block natural water flow, increasing the risk of wildfires.
The interruption of water flow would likely also increase flooding in the states along the U.S. border. Floods due to barriers on the border have occurred in the past. The 700 miles of fencing along the border of Arizona put in place by the Bush administration caused several flash floods in 2008. These prior floods should be considered during any talks of a border wall.
Water and plants are not all that would be separated by the wall. A border wall would cut off around half of certain animals’ territory. This would limit the migration patterns of animals as well as interrupt their hunting and grazing. Even some species of owls would not be spared by the wall as they can only fly around five feet from the ground.
Perhaps the most frightening aspect of the border wall is the governments knowing ignorance of its own environmental oversight laws. Though the current border wall proposal would normally violate more than 30 federal environmental laws, the REAL ID Act passed by Congress in 2005 authorizes Homeland Security to ignore these laws in the name of national security. I would argue that the border as it is now, while an issue, is not a pressing matter of national security. As such it would be foolish to ignore the environment and our own environmental laws to pursue the wall.
Again, not only would the wall separate countries, it would separate endangered animals and plant life from what they need to survive. If the border wall is constructed, small, easily-patrolable sections of the border should at least remain untouched to maintain migration and hunting paths. These innocent bystanders in the debate between political parties in the United States deserve to be considered before any decision on a border wall is made, lest we once again deal a blow to the environment we can’t take back.