A last-minute border security deal will prohibit construction of border fencing at several environmentally sensitive and culturally important sites in the Rio Grande Valley, but will put nearly $1.4 billion toward another 55 miles of new fencing for the region.

The legislation carves out protections for the 150-year-old La Lomita chapel, the Bentsen-Rio Grande Valley State Park and the National Butterfly Center in Mission. The sites had been the focus of intense protest and legal battles in recent weeks and months. The legislation also protects land near SpaceX in Brownsville.

President Donald Trump plans to sign the spending bill, avoiding another government shutdown, but also will declare a national emergency to bypass Congress and build his long-promised wall, said Sarah Huckabee Sanders, White House press secretary.

A bipartisan committee that hashed out the compromise adopted provisions added last month by U.S. Rep. Henry Cuellar, D-Laredo, to protect the sites. The Santa Ana National Wildlife Refuge had previously been removed from funding approved last year to build 33 miles of new border fencing in Hidalgo and Starr counties.

The border deal includes funding for an additional 55 miles of fencing in the U.S. Border Patrol's Rio Grande Valley sector, bringing the total of new fencing authorized in the area to nearly 90 miles. Much of that fencing would likely be slated for Starr County, which currently has no fencing. Last year's spending bill will bring about eight miles of fence to the county, mostly in the cities of Roma and Rio Grande City. Border Patrol officials have called the county the most "volatile" along the border, citing its high numbers of illegal crossings and marijuana seizures, but opponents say a border fence will exacerbate flooding concerns.

Marianna Treviño-Wright, executive director of the National Butterfly Center, said she worries Trump could still seek to place additional border barriers through the 100-acre center. The border fence had originally been set to follow a levee that bisects the center's property, that would leave 70 acres south of the fence.

"It feels like a stay of execution," she said Thursday. "The president hasn't signed it yet and there is no assurance he won't declare a national emergency and run bulldozers over us anyways."

Last week excavators began arriving in Mission and fence construction is expected to begin this month on sections of the Lower Rio Grande Valley National Wildlife Refuge owned by the U.S. Fish and Wildlife Service. On Thursday morning, conservation photographer Krista Schyler posted a Facebook video of what appeared to be crews beginning work on the Wildlife Refuge's La Parida tract, adjacent to the Butterfly Center and state park.

"What about our neighbors?" Treviño-Wright said. "It's hard to celebrate."

Critics also took issue with the notion that the legislation had not allowed solid walls in the Rio Grande Valley, where geography prevents solid barriers because of potential flooding from the Rio Grande.

Last year, in public documents relating to upcoming construction in Hidalgo and Starr Counties, U.S. Customs and Border Protection officials referred the planned barrier as both a "border wall system" and "levee wall system."

"Some lawmakers have made a distinction between funding 'fences' instead of 'walls,' but the barriers allowed under this agreement will do the same amount of damage to wildlife, the environment and borderland communities," the Arizona-based Center for Biological Diversity said in a statement.