Spring doesn't bring just robins to Capitol Hill: it brings political trail balloons.

With that in mind, be advised that Congress is looking at some alternatives to the president's plan to cut federal pay by 5 percent. Some of the deficit-reducing items on the drawing board include plans to:

* Make federal and postal workers put 9 percent of their salaries into the civil service retirement fund. Most now contribute 7 percent. So the proposal, if enacted, would mean a 2 percent pay cut for most workers, while at the same time saving the government millions of dollars.

* Freeze, rather than cut, federal pay in January.

* Freeze for at least one year all within-grade (longevity) pay raises.

* Skip a multimillion-dollar cost-of-living-adjustment due next December for retired federal and military personnel.

The administration is still sticking to its proposal to cut civil service pay next year. But it would go along with other money-saving ideas, if Congress prefers to take another route.

Judging from budget debates on Capitol Hill, Congress isn't wild about the idea of cutting federal pay, because it would alienate civil servants and their families and have a major impact on the economies of many large and small towns. The Washington area would lose $2 million a day if such a cut went into effect.

Earlier this week, Senate Budget Committee Chairman Pete V. Domenici (R-N.M.) unveiled a plan to trim the federal deficit by $300 billion over three years without requiring feds to take a pay cut. But it would eliminate the next COLAs due for Social Security and civil service benefits.

Government Affairs Committee Chairman William V. Roth (R-Del.) has said previously that he opposes the 5 percent pay cut, but is willing to look at a freeze on longevity pay raises -- worth about 3 percent -- that go to nearly half the federal work force each year.

Civil servants now get the within-grade raises every one to three years, depending on their time in their pay grades. Only when employes reach the 10th step of their grades -- and that takes 18 years -- are they ineligible for the longevity increases.

Since turnover is highest among newer civil servants -- who get within-grades the most rapidly -- a high percentage of U.S. workers get two raises a year.

Nobody doubts that major cuts in federal benefits will be made. The question is where, and how deep they will be.