（文/ April Reese）
According to the latest report by Scientific American, residents of smaller cities in southern Texas are already familiar with which streets to avoid and how to avoid them as streams rise. Now, the government plans to build a 30-foot-tall steel border fence between the city and the Rio Grande River, which is likely to exacerbate local flooding and raise concerns among locals.
Heavy rain can take away debris and trash, but fences can cause debris to pile up here, blocking the natural path of the water flow. Over the past 15 years, Customs and Border Protection has built steel fences almost everywhere, and residents of the local community of Rio Grande can only watch the flooding get worse and worse.
Scientists have paid particular attention to and documented changes in the lowland environment in the Rio Grande Valley, Texas, one of the most ecologically diverse areas along the U.S.-Mexico border and home to many farms and towns. Customs and Border Protection (CBP) has proposed the construction of a 95-mile new steel fence in the Rio Grande Valley lowlands. In the city of Rio Grande and five other neighborhoods nearby, about 14 miles of walls will be built. To this end, the city is also engaged in a fierce dispute over the new wall project.
This has been the case for a long time, and plans to build a border wall here in 2008 were shelved due to flooding. However, the Trump administration restarted the project, citing a large number of illegal border crossings in the region. And in the debate, getting Customs and Border Protection (CBP) to make any concessions is very difficult.
Under the 1970 treaty between the United States and Mexico, the two countries must ensure that any buildings built along the Rio Grande River do not cause "deflection or obstruction" of the river's normal flow or flood flow. In 2008, the International Border and Water Commission, a bilateral agency that ensures compliance between the two countries, warned Customs and Border Protection in a letter that the Rio Grande boundary wall project would exacerbate flooding in nearby towns and divert flooding to Mexico. After several failed attempts, Customs and Border Protection shelved the Rio Grande Project.
Customs and Border Protection (CBP) tried again in 2011: using different hydrological models to analyze the flood impact, concluding that debris from the fence during the storm would cause only a small blockage, and U.S. IBWC officials withdrew their opposition to the project.
So far, Customs and Border Protection (CBP) has held two rounds of meetings with local officials to discuss other options. The city of Rio Grande's plan would build a 25- to 35-foot-tall flood wall and use electronic surveillance instead of fencing to cover the rest of the city's border. Other areas of Stahl County, southern Texas, would build an 18-foot-tall steel fence and install electronic monitors or flood walls. Whether locals want to or not, it is imperative to build a border wall. As a result, local officials tried to optimize the construction plan through discussions. At their Sept. 25 meeting, they asked Customs and Border Protection (CBP) officials to consider rotating the steel balustrades laterally to create larger gaps that allow water to flow through where the creek intersects the fence.
Finding a compromise is not an easy task. Customs and Border Protection (CBP) rejected the Rio Grande's electronic surveillance scheme. Following further hydrological studies, at least one more meeting is expected in the coming weeks. It's unclear how much the local city's proposal will have an impact on customs and border protection's final design. While local officials say Customs and Border Protection appears to have accepted some of their recommendations, the agency has made it clear that its priorities in developing its rio Grande Valley wall plan are to deter illegal activities, comply with treaty requirements, and consider local inputs and conditions as a secondary consideration.