The Trump administration says the border wall is good for the environment. It isn't.

In 2016, the border wall was one of the signature issues of Donald Trump's presidential campaign. It's currently quite unpopular. More than 60 percent of people oppose the border wall, according to a Gallup poll conducted earlier this year. To improve public interest in the issue, the Trump administration is rolling out some new claims to try to give the $21 billion boondoggle fresh appeal. Its latest claim: the border wall will be good for the environment.

According to a press release published last week, the Bureau of Land Management (BLM) is currently in the process of assessing the environmental impact of border crossings in hopes of pitching the border wall as an environmentally conscious project. "Illegal crossings are destroying our wilderness areas with unlawful fires, trash, foot traffic, and trails," BLM deputy director for programs and policy William Perry Pendley said in a statement. "The federal government will not only address the humanitarian and national security crisis facing our nation, but allow the BLM to address the environmental crisis impacting our nation’s most vulnerable lands.” According to the BLM, border crossings are responsible for "land degradation and destruction caused by the creation of unauthorized trails, the deposition of trash, and unlawful fires."

The solution to that, in the eyes of the Trump administration, is to dig up thousands of miles of land and impose an artificial barrier directly in the middle of existing ecosystems. Pretending just for a moment that one of the missions of the border wall is to protect the environment, it is an extremely ineffective tool to accomplish that goal. The U.S.-Mexico border runs across 1,954 miles, reaching from the Gulf of Mexico in Texas all the way to the Pacific Ocean in California. That huge stretch of land contains six separate eco-regions, according to National Geographic, and an incredibly biodiverse area. There is desert, forest and wetland across the border, and those regions are home to more than 1,500 native animals and plants — 62 of which are listed as critically endangered, endangered or vulnerable. They will be put even more at risk, pushed to the brink of extinction, should a massive barrier be placed directly in the middle of their environment.

In a paper published in BioScience, experts in the field warned that large-scale development projects like the construction of the border wall would do unimaginable damage to the surrounding environment. Remember, it's not just the wall that has to be built. Roads have to be made to bring necessary equipment to the construction site; massive and disruptive vehicles needed to build the wall will operate, creating noise and light distractions that chase off wildlife; soils will end up eroded from being driven on and disrupted — and that's all before the actual wall itself goes up.

Once the wall is actually in place, entire ecosystems would be cut off. A 2011 study looking at the creation of any new barriers along the border — well before Trump's proposal of a 30-foot-tall wall stretching across the entirety of the land — found that any such barrier would put more species at risk, forcing them out of familiar habitats and into new areas where they are at risk of extinction. The paper published in BioScience expanded on these findings, noting that a border wall would degrade "landscape connectivity" and would make it challenging for animals cut off from their habitat to re-establish themselves in an unfamiliar environment. The wall would physically prevent them from accessing food and water, and could split the population of a species across two different areas. Fragmented populations reduce genetic diversity and increase the likelihood of extinction, according to the paper. Many animals will also be cut off from their annual and seasonal migration patterns, which will threaten their long-term viability as they will be stuck in regions that may not be ideal for their survival during different parts of the year. That issue will only be exacerbated by climate change, which has already pushed animals to cooler climates — except now those animals will be physically cut off from migrating. According to the BioScience study, a continuous border wall could cut off as much as 34 percent of all non-flying native animal species from more than 50 percent of the land that would typically make up their ecosystem.

Then there's the potential for flooding. The way things currently work on the border, creeks typically carry excess water kicked up by heavy rains. Instead of flowing freely and naturally, that water would be trapped by fencing and walling that cut across those creeks. That water would have to be dispersed somewhere, which could lead to flooding that would disrupt both plants and animals as well as nearby residential areas. Existing fences and border walls have already made flooding worse basically everywhere they have been built, and Trump's proposed wall would simply serve to make the issue worse.

It might seem that for any sort of structure like the border wall to go up in such a biodiverse region of the country, particularly in areas that endangered species call home, a significant amount of effort would have to be put in to ensure that the construction would not have adverse effects on the environment. Under normal circumstances, that might be the case. The border, however, is an exception. Construction of the border wall is not required to meet the requirements established by the Endangered Species Act, National Environmental Policy Act, the Clean Air Act, the Clean Water Act or any of more than 37 federal laws meant to help protect the environment. This is because of the REAL ID Act, passed by the US Congress in 2005. The bill, which was part of an anti-terrorism push in the Republican-controlled House and Senate, authorizes Homeland Security to waive any laws that it needs to if it is determined to be necessary for national security. That broad, sweeping and essentially unchecked power gives the agency carte blanche to do what it wants at the border, including forgoing any environmental studies when building a wall — as long as it can make a feasible claim to protecting the safety of the country.

The idea that the border wall is part of an effort to protect the environment is a farce. The Trump administration has proven time and time again to be entirely disinterested in any sort of environmental causes. Trump has signed executive orders to shrink the borders around national monuments in order to allow for expanded oil drilling, scrapped laws designed to preserve coastal areas near oceans and the Great Lakes, lifted rules requiring projects to consider their environmental and climate impact, rolled back protections for endangered species and generally dismissed any suggestion that protecting the environment should take any priority over his oil drilling, coal mining, wall building agenda. The whole argument being put forth by BLM that it is concerned about the environment is immediately undermined by its messenger. Director Pendley has called the scientific consensus on climate change "political science or junk science, not real science.” He tweets under the handle sagebrush_rebel, which is a reference to the Sagebrush Rebellion movement of the 1970s and 80s that pushed for the transfer of control of federal land back to states so it could be used for oil and gas drilling and mining. Pendley does not care about the environment, nor does Trump. Meanwhile, more than 2,500 scientists whose job it is to care about these issues have signed a petition urging the administration not to build the wall for fear of destroying biodiversity across the border.