McALLEN, Texas (AP) — An agency that monitors the U.S.-Mexico boundary is agreeing to a U.S. proposal to build border fence segments in a South Texas flood plain, a move Mexico opposes.
The decision by the U.S. International Boundary and Water Commission comes despite objections from its Mexican counterpart. Mexico argues the fence would deflect floodwaters to its side of the Rio Grande and violate a bi-national treaty.
The Associated Press on Tuesday obtained a letter the commission sent to U.S. Customs and Border Protection noting it will not oppose the project. The commission says its analysis found that the fence proposed for three areas in South Texas would not be a significant obstruction to river waters. Half of the 14 miles proposed would be in the flood plain.
"When it comes right down to it, the scientific analysis is what we have to fall back on," John Merino, principal engineer with the U.S. commission, said Tuesday.
In his February letter, Merino wrote that after a thorough review, the agency concluded that the project "will not cause significant deflection or obstruction of the normal or flood flows of the Rio Grande" and is consistent with the treaty.
Jenny Burke, a spokeswoman for U.S. Customs and Border Protection, said that one of the segments, in Los Ebanos, is no longer considered necessary and more funding is needed to build the other two in Rio Grande City and Roma. Merino also pointed out that the government would have to bring back detailed construction drawings of the fence for approval before proceeding.
Still, the green light for a permanent fence made of spaced vertical steel tubes is a significant reversal for an agency that expressed concerns when the government was still proposing a "moveable" fence in 2008.
A 1970 treaty between the United States and Mexico called on both countries to prohibit the building of anything that "may cause deflection or obstruction of the normal flow of the river or of its flood flows."
In July 2008, Al Riera, then the principal operations engineer for the U.S. boundary commission, told a citizens forum, "If they (Department of Homeland Security) don't show us they have something in place to guarantee removal of the (fence) panels ... the commission would never agree to something like that."
That movable fence was planned to involve a base of concrete barriers topped with about 15 feet of tightly woven steel fencing that could be removed in advance of floodwaters.
Merino said the project had not been analyzed when Riera made those comments. Riera is no longer with the commission.
But a letter from a Mexican engineer to Merino in December 2011 said the project represented a serious obstruction.
"The location, alignment and design of the proposed fence represent a clear obstruction of the Rio Grande hydraulic area, since in the towns of Rio Grande City and Roma, (Texas), the fence would occupy nearly all of the hydraulic area on the U.S. side, causing the deflection of flows towards the Mexican side," wrote principal engineer Luis Antonio Rascon Mendoza.
Jesus Luevano, secretary of the commission's Mexican section, said in an email Tuesday that Mexico's position is that the "wall constitutes an obstruction of the normal current ... in terms of the 1970 Boundary Treaty, therefore we continue fighting its placement with respect to the Rio Grande flood zone."
He added that Mexico recognizes the border fence is a unilateral endeavor, but said it wasn't improving relations between the neighbors.
The U.S. has built about 650 miles of border barriers along the 1,954-mile U.S.-Mexico boundary. In Texas, the fence segments have been built more than a mile away from the river in some rural areas, but the three segments recently reviewed by the commission would be built closer because all three communities abut the river. In 2008, the Department of Homeland Security waived a host of environmental regulations to allow speedy construction.
Merino said the disagreement stems from differing assumptions. He said Mexico looks at the fence as a solid barrier like a dam that would not allow water to pass through. U.S. engineers believe water will pass through it as long as it's kept free of debris.
Jeffrey Ruch, executive director of Public Employees for Environmental Responsibility, or PEER, said he will send a letter to the commission Wednesday demanding an explanation for the agency's new position. He noted that the proposed fencing would cut through a national wildlife refuge.
"We don't know the reason that all of these concerns evaporated," Ruch said Tuesday.
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