The Endangered Species Act may be endangering 52 federal projects ranging from the $1.4 billion Tennessee-Tombigbee Waterway to small stream-dredging operations in Virginia and Maryland, the administration said yesterday.

However, officials testified, the conflicts probably can be resolved without dooming any wildlife and without changing the Endangered Species Act which was designed to save it.

A Senate Environment and Public Works subcommittee opened hearings yesterday on whether to amend the act, which has been used to stop construction of a $116 million Tenneessee Valley Authority dam. The almost-completed Tellico Dam would flood a 17-mile stretch of the Little Tennessee River deemed essential to the survival of a three-inch fish called the snail darter.

More than 600 species of animals, fish, and reptiles are officially listed as dengered and 2,000 others are under consideration for listing. Under the act, no federal project can be built that would harm an endangered species.

An Interior department list of 52 possible conflicts included:

Another TVA Dam in Columbia, Tenn., which could wipe out the bird-wing pearly mussel, the Cumberland monkey face pearly mussel, the turgid riffle shell and the orange-footed pimple back mussels.

The Tennessee-Tombigbee Waterway, a giant canal which would link the Tennessee River with the Gulf of Mexico, which could endanger 13 species under consideration for listing, including two types of darters, the Alabama red-bellied turtle and a fish called the frecklebelly madtom. The waterway is 20 per cent complete.

The Army Corps of Engineers' proposed Lukfata Dam in Oklahoma which could affect the Lukfata jewel flower and the leopard darter fish.

Stream channeling along the Chester River in Maryland's Eastern shore which might harm the Delmarva forx squirrel, and in Virginia's Upper Clinch Valley which could affect dozens of rare mussels and fish.

Sen. James A. McClure (R. Idaho) and Howard Baker (R.-Tenn.) critized the Endangered Species Act as being inflexible. Unless it is amended to allow the balancing of environment with energy and economic issues, it will be used as "a weapon" to stop important dams and other projects, McClure said.

However, Charles Warren, chairman of the Council of Environmental Quality, and Robert Herbst, assistant secretary of Interior, strongly opposed any major changes in the act.

"The act is flexible," insisted Herbst, adding that out of 4,500 consultations between Interior and other agencies over endangered species, only three projects have gone to court. Only one -- Tellico Dam -- is unresolved, awaiting Supreme Court review.

Most situations can be resolved without scrapping the project, Warren said. For example, after the Federal Highway Administration was told it could not build an interchange because it would disrupt a group of Mississippi sandhill Cranes, arrangements were made to preserve the cranes by purchasing 1,900 acres for a refuge, he noted.

In a case involving the Meramec Dam in Missouri, which Interior officials claimed would harm the Indiana bat, a court determined the bat would survive. The project was abandoned for other reasons, Warner said.

Although the snail darter is being used to stop the Tellico Dam, Herbst questioned "whether the project is a valid, cost-effective use of the Little Tennessee River." He cited a General Accounting Study, to be released today, that recommends halting the project until its costs and benefits are reassessed.

Despite the controversy, there seems to be little immediate sentiment in Congress to amend the act, a sub-committee aide said.