A section of the border wall in Arizona caused severe erosion in Organ Pipe National Monument during a rain storm earlier this summer. During heavy rain storms, flood water usually flows south, across the site of the wall. During the rain storm on July 12, debris carried by the flood blocked the openings in the wall so that water flowed laterally along the wall. The result was much more severe erosion damage than would have occurred if the wall were not there.
The scandalous part is that environmental organizations and the National Park Service predicted that this would happen last year, but the Department of Homeland Security ignored their concerns.
Though Baiza declined to join the chorus of "I told you so," the report shows that he and other Organ Pipe officials also warned Homeland Security about water-flow issues before construction began.According to the National Park Service, rainfall events like that on July 12 occur about once every three years. The Department of Homeland Security ought to fix this faulty section (and any others like it) before the next one. It is bad enough that this happened once; it should not happen again.
In October 2007, Organ Pipe officials told Homeland Security they were worried that the fence would impede the movement of floodwater across the border; that debris would get trapped in the fence; that backwater would pool up; and that the lateral flow of water would cause damage to the environment and patrol roads, the report said.
In response to those concerns, the Border Patrol issued a final environmental assessment with a finding of no significant impact that said the fence would not impede the natural flow of water or cause flooding, the report said.
The agency said it would remove debris from the fence within the washes and arroyos immediately after rains to ensure no flooding occurred.
At a December 2007 meeting, Kiewit officials stated in a handout that the fence design "would permit water and debris to flow freely and not allow ponding of water on either side of the border" because the drainage crossing grates "met hydraulic modeling requirements."
By the way, this is a good example of why agencies should not be allowed to perform and approve their own environmental assessments.
[via No Border Wall]