Alternative proposals on a major environmental controversy - how to manage Glen Canyon Dam - are to be discussed in a set of three hearings scheduled for early April, the first of which will be in Salt Lake City.

Federal studies have shown that fluctuating water flows in the Colorado River resulting from the dam's power generation caused environmental damage downstream in Grand Canyon National Park. Beaches have been destroyed and fish have been stranded by sharp changes in the river's level.Environmentalists pushed for changes in Glen Canyon Dam's operations to lessen the damage. This pressure caused the federal government to begin environmental studies of the dam's management.

The U.S. Bureau of Reclamation set the Utah hearing for April 1, starting at 7 p.m. in the Hilton Hotel, 150 W. 500 South. The other meetings are in Flagstaff and Phoenix, Ariz., on April 2 and April 4, respectively.

The bureau is the lead agency in producing an environmental impact statement on operation of the dam. Other agencies cooperating in the effort include the U.S. Fish and Wildlife Service, National Park Service, U.S. Bureau of Indian Affairs, Western Area Power Administration, the Arizona Game and Fish Department, and the Navajo, Hopi, Havasupai and Hualapai Indian tribes.

The statement "will consider the impacts of current operations of Glen Canyon Dam on downstream environmental and ecological resources in Glen Canyon National Recreation Area and Grand Canyon National Park," said Barry Wirth, spokesman for the Bureau of Reclamation in Salt Lake City.

"It will also evaluate alternative operational possibilities for the dam. Any changes in operations would be the result of a decision by the Department of the Interior."

The draft environmental impact statement is scheduled to be released in July 1992. A final statement is due out in September 1993.

In the meetings, representatives of the agencies preparing the statement will discuss the range of alternatives to be studied, as they currently view them. They will describe the alternatives, but won't be able to talk about the alternatives' impacts - that will be the job of the statement.

A written-comment period concerning which alternatives should be studied will last through April. Meanwhile, those wishing to receive written information about the studies can contact the bureau's Colorado River Studies Office in Salt Lake City at 524-4099.