McALLEN, Texas - A new map showing President Bush's planned border fence has riled Rio Grande Valley officials, who say the proposed barrier reneges on assurances that the river would remain accessible to farmers, wildlife and recreation.

City officials in the heavily populated valley had anticipated a "virtual" fence of surveillance cameras and border patrols. Instead, a Customs and Border Protection map depicts a structure running piecemeal along a 600-mile stretch of Texas from Presidio to Brownsville, a border region where daily life is binational.

Mike Allen, head of McAllen Economic Development Corp., said: "We were given the impression that they were not going to be building walls, that there would be more cameras, surveillance, boots on the ground.

"This is going to seriously affect the farmers. They will not have access to water. It's just going to create bedlam."

The map, obtained by the Associated Press, was attached to a memo addressed to "Dear Texas Homeland Security Partner." It outlines a plan to build 370 miles of fence and 200 miles of vehicle barriers by the end of 2008.

Of the 370 miles of fence, Texas is to have 153, Arizona 129, California 76, and New Mexico 12. Most of the vehicle barriers will be in Arizona and New Mexico.

Russ Knocke, a spokesman for Homeland Security Secretary Michael Chertoff, said the so-called virtual fence would not work in urban areas and said the federal government had delivered a consistent message to local officials.

"We are utilizing traditional fencing at the border generally in those areas, including metropolitan areas, where it is easier for an alien . . . to conceal themselves in a home or a business," he said.

Knocke said agents would use such advanced technology as sensors, radar and aerial drones in remote border areas.

Environmentalists fear that the fence will block Rio Grande water access to endangered cats such as ocelots and jaguarundi and ruin key feeding and resting areas for migratory birds. Knocke said that environmental assessments were being conducted but that border security outweighed such concerns.

"There's an expectation by the American people that we secure our borders," he said.

Chertoff has already waived requirements to get permits in environmentally sensitive areas to expedite construction of the fence, Knocke said.

Hidalgo County Judge J.D. Salinas said the fence would also damage the regional economy, which thrives on cross-border commerce.

Mexicans cross daily to make bank deposits, buy real estate, shop, and work - activities that Salinas said would be threatened by the ill feelings generated in Mexico by the fence.

"Irrigation, that's one concern," Salinas said. "The other is the indirect message you're sending to your neighbor to the south."

Bush called last year for 700 miles of fence, and Congress approved it. Of the $1.2 billion needed, at least $400 million has already been appropriated, Rep. Henry Cuellar (D., Texas) said. He said the Democratic-controlled Congress could modify the law or withhold funding.