Border fence knocked down by rain water

Last week water from a rainstorm knocked over a forty-foot section of the U.S-Mexico border fence in Southwestern Arizona.

The fence was originally built in 2007 and at the time officials from the Organ Pipe Cactus National Monument warned U.S. Customs and Border Patrol that the fence’s design would create environmental and structural problems.

According to Lee Baiza, Organ Pipe Cactus National Monument’s superintendent, the fence does not permit water to flow naturally along washes. In these washes, the fence has grate openings at the bottom that are six inches high and twenty-four inches wide covered by one by three inch bars.

“The fence acts as a dam and forms a gradual waterfall,” Baiza said. “It starts to pile up on the bottom as the grass, the leaves, the limbs start plugging up. The water starts backing up and going higher. The higher it gets, the more force it has behind it.”

The latest storm dropped 1.5 to 2.4 inches of rain in an area upslope from the section of fence that had been destroyed. Large bursts of rain like this are common in the national park, but this is the first time any part of the 5.2 mile section of fence has been knocked down.

Baiza believes that other parts of the fences in natural washes are at risk of being knocked over in the future.

At the time of the fence’s construction Organ Pipe officials requested Border Patrol to take into account the natural washes, but the agency said that it would remove debris from the fence within the washes to ensure that no flooding would occur. In addition the Border Patrol said that its fence design would allow debris to flow freely.

Contrary to Border Patrol’s claims, the fence has had several problems over its short lifespan.

In 2008 after a storm dumped one to two inches of rain in ninety minutes, one section of the fence halted the natural flow of floodwater and when water began to pool around the fence it flooded the town of Lukeville, Arizona damaging several local businesses.

In addition the fence caused last week’s storm water to backup resulting in the flooding of several buildings in Lukeville once more.

Matt Clark, the Southwest representative for Defenders of Wildlife, says that last week’s events show why border fences should not be built at water crossings, instead officials should use alternatives like ground sensors to allow flood waters to move freely as well as wildlife.

“Flooding is a very visual and physical reminder that walls block ecosystem processes,” Clark said. “There are major costs both fiscally and environmentally to building walls across watersheds.”

To help reduce flooding, in 2010 the Army Corps of Engineers built a series of fifty to sixty moveable gates in eleven drainage systems to reduce the build-up of rainstorm runoff. For the system to work properly, the gates must be raised during storms so water can flow freely.

Last week the gates were down during the storm.