Last year the old wooden lodges at Yellowstone National Park were in need of repairs, two bridges in Great Smoky Mountain National Park were thought to be unsafe to cross, and the chairs at Independence Hall in Philadelphia needed to be recovered.

But now the Interior Department says it is on course in its 18-month-old campaign to restore these and scores of other facilities at many of the nation's parks.

The agency calls the effort PRIP -- for Park Restoration and Improvement Program -- and considers it a cornerstone of Secretary James G. Watt's management plan for the Interior Department.

The fiscal 1983 PRIP agenda includes spending $2.16 million to reconstruct 35 miles of Skyline Drive in Shenandoah National Park, upgrading the street lights on the Mall ($156,000), correcting erosion problems on George Washington Memorial Parkway bridges ($120,000), widening and resurfacing four miles of park roads at Hawaii Volcanoes National Park ($1.5 million), and restoring the exterior of the old courthouse at the Jefferson National Expansion Memorial (otherwise known as the St. Louis arch) for $2.3 million.

"We developed a blueprint and we're executing it," said Ira J. Hutchinson, the Park Service's deputy director. "The notion of a fixup, cleanup at the expense of everything else is not true. I don't feel we are abdicating any professional responsibility mandated to us."

Hutchinson is on the defensive because environmental groups have charged that Watt's fixup program is designed to divert funds that otherwise would be used to buy new parklands. Congress has steadfastly refused to take money out of the Land and Water Conservation Fund -- generally used for parkland acquisitions -- to pay for the repair program.

"We basically gave the secretary everything he requested" for fiscal 1983 improvements, said Frederick G. Mohrman, a staff member of the House Appropriations subcommittee that handles the Interior budget. "But we want the acquisitions to go on."

The department has continued to move on previously authorized parkland acquisition -- though at a slower pace than Congress had intended. Watt has also used some money to settle legal disputes over small parcels of potential parkland.

T. Destry Jarvis, director of federal programs for the National Parks and Conservation Association, said Watt's leadership has been overstated because he merely continued a fixup program that Carter administration officials began. But Daniel Salisbury, associate director of the Park Service for administration, noted that Watt doubled the $80 million that the Carter administration had projected spending on park repairs in fiscal 1982. This year Watt has sought $203 million for the program.

The Park Service is happy to let the private sector pick up the costs of repair work if someone is interested. Thus, the Statue of Liberty is being repaired this year as part of a private project to turn Ellis Island, where many immigrants arrived in the United States, into a national historic site and commercial development.

"There are rundown water, sewer systems and roads in parks, but . . . by and large the parks were not in as shameful condition as Watt says," Jarvis said, adding that it is more important to buy new parkland than to round out existing park units. "Watt has basically tried to scuttle every other program and put the need and emphasis on only those things that are visitor-use oriented. He's neglected the resource base."

Watt has dismissed such criticism. For example, in a report to President Reagan last January, he said: "In recent years, the funding and manpower resources of the department have not been adequately directed to fulfilling proper stewardship responsibilities. Contrary to often-repeated inaccuracies, we pledged that the national parks are inviolate and will be protected from mining, drilling and logging."

Park Service officials say the latest cleanup effort was Watt's response to a highly critical "State of the Parks" report the agency prepared in 1980. It identified thousands of problems, ranging from those caused by ever-increasing numbers of visitors to esthetic concerns such as nearby development or timbering.

"These are all problems that are not unique to the national park system," Hutchinson said. "They are interdependent problems."