IT SEEMS STRANGE that, in this year of Proposition 13 and all the talk about a taxpayers' revolt, a president should find it necessary to denounce, once again, "pork-barrell allocations." But Mr. Carter was absolutely right to do so at his press conference Thursday. The pork barrell is rolling wildly around on the Hill this fall and Congress is dancing with joy as more and more goodies are stuffed into it.

Those goodies - pet projects of members of Congress who want something for their friends or the folks back home - are not confined to the public works bill, which the president has threatened to veto. They can be found elsewhere, too - in the highway bill, the parks bill and the tax bill, to mention just a few. Not every project or proposal in those bills can be described as pork. But enough of them can be to make all the bills highly suspect.

The public works authorization bill, for example, directs the Corps of Engineers to built free water systems for Caesar Creek and East Fork Lake, Ohio. The highway bill mandates a rural public-tranaportation system for the vicinity of Sherman and Dension, Tex. The parks bill creates or expands federal facilities in more than 35 states, including new historic sites in Charles County, Md., and Richmond, Va. The tax bill includes an exception to benefit two large chicken farms, one in Maine and one in Arkansas. The list goes on and on.

Both parties have a piece of the action. Republicans have been just as busy, and just as successful, as Democrats in putting projects into the barrel. Those water systems, for example, go to cities in the district of the senior Republican member of the House Public Works Committee, Rep. William E. Harsha. And that new historic site in Charles County - the home of Thomas Srone - is the pet project of the great Republican watchdog of the House, Rep. Robert E. Bauman.

If Congress goes through with what now appears to be its intention of approving this welter of projects, President Carter should not haver the slightest qualms about using his veto power extensively, even though Senate Majority Leader Robert C. Byrd (D-W.Va) has said he would try to override a veto of the public-works bill. Mr. Carter will need to explain his actions with some care - considerably more than he exercised in explaining the nuclear-carrier veto - because each of these hundreds of projects has its won core of supporters. But the mood of the country is like to be with him and not with those in Congress who are filing the barrel as if there were no tomorrow.