EVEN BEFORE taking office, Virginia Gov.- elect Gerald L. Baliles is making it clear that the meek shall not inherit the State House in Richmond next Saturday. Mr. Baliles has just tackled a time-honored big issue in the Old Dominion: the power and glory of the Virginia Highway Department. Moving in where even Gov. Charles Robb feared to tread, Mr. Baliles says he will oust the state's highway commissioner, Harold C. King, who has run the roads with a strong hand ever since his nomination to the job seven years ago by Republican Gov. John N. Dalton.

It's time. The job will go now to Ray D. Pethtel, who has headed the Joint Legislative Audit and Review Committee for 12 years -- and who played a key role last year in rewriting and improving Virginia's highway financing formulas. This puts two highly respected and knowledgeable people in position to redefine the state's transportation policies, in line with their previous work together on the formulas: Mr. Pethtel and Vivan E. Watts, the governor-elect's choice for secretary of transportation and public safety, understand the regional concerns of Northern Virginia and other growing areas of the state and were instrumental in winning legislative approval of a move away from old formulas that favored rural areas.

Mr. King has been an effective administrator and did improve the professional quality of the department, having taken over from an entrenched bureaucracy. But his loyalty to the highway agency came to be overly protective of the department's power. The result was a department becoming increasingly out of touch with dramatically changing transportation needs around the state.

The fun has just begun too, because financing of the state's transportation needs is expected to be a dominant issue in the General Assembly session that starts Wednesday. Northern Virginia and other populous parts of the state will be seeking urgent relief for traffic congestion. At the same time, the more rural regions will continue to press for their long-awaited road projects. How all of this can -- or will -- fit into a balanced and politically plausible policy will be up to Mr. Baliles to initiate. In choosing Mr. Pethtel, the governor-elect has made this mission more possible.