GRAND ISLAND, Neb. (AP) - The proposed Platte recovery plan eventually could take a half-million irrigated acres out of production, says a report commissioned by the Central Platte Natural Resources District.

The economic impact analysis, released Thursday, also said the proposed Platte River Recovery Implementation Program could have an economic impact of as much as $730 million over the next 50 years.

The analysis said the primary beneficiaries of the recovery plan would be entities that take water directly from the Platte River, including the Panhandle irrigation districts, Central Platte Public Power and Irrigation District and Nebraska Public Power District. Their estimated beneficial effects total about $247 million over the first 13 years of the program.

Groundwater users would suffer the great harm from the program, the analysis said. The estimated harm to the state and to groundwater users would total $261 million by 2020, the report said, and come from offsetting any post-1997 depletions to Platte River flows.

NRD board member Marvion Reichert of Elm Creek said farmers shouldn't have to give up so much water to protect four species.

"It's a shared sacrifice," he said. "Why should a few bear the burden of the many?"

Like Nebraska's 22 other natural resources districts, the Central Platte NRD manages groundwater resources in the district, which runs roughly parallels the Platte through the south-central part of the state.

"Groundwater is a major input to the economic well-being to our natural resource district," said Ron Bishop, Central Platte NRD manager.

Last month, the NRD board voted to urge Gov. Dave Heineman not to sign the three-state cooperative agreement on the Platte recovery.

On Thursday, board members decided to send another letter to Heineman, telling him of their continued opposition to the plan.

The governor's office said Friday morning that Heineman would be announcing his decision later in the day.

The governor has sought input from across the state in three forums in September and October.

Last week an advisory group voted 18-3 to recommend that Heineman sign the agreement.

The agreement between Wyoming, Colorado, Nebraska and the U.S. Department of the Interior would guide Platte River Basin entities in complying with the Endangered Species Act while retaining their access to federal water, land or funding.

The goal is to improve the Platte River and protect habitat for the whooping crane, piping plover, interior least tern and pallid sturgeon.

An estimated $157 million of the cost would come from the Interior Department and the rest would come from the states: Colorado plans to pitch in $24 million in cash, and Wyoming $6 million in cash.

The remaining $130 million is being contributed with water and land credits: The three states must together contribute 80,000 acre-feet of water, an estimated $120 million value, and Wyoming and Nebraska will contribute about 26,500 acres of land, a $10 million value.

The plan would be implemented in phases, with the first lasting about 13 years.

Bishop said his Central Platte NRD includes about a million acres of irrigated land - about half the total irrigated in the Platte River Valley.

He said thousands of acres would have to be taken out of irrigated production from North Platte to Kearney to increase the river flows.

"This could hit Lincoln, Keith and Dawson counties very hard," Bishop said. "This could be devastating to the economies of a lot of our small towns."

Last week, state Attorney General Jon Bruning advised Heineman that he or subsequent governors could pull Nebraska out of the cooperative agreement later if it proved too harmful to the state.