RICHMOND, AUG. 3 -- Virginia government officials, opening the second phase of a mammoth transportation financing program, proposed today giving the state's most congested localities broad new powers to raise taxes and fees to finance traffic improvements.

In presenting a menu of 18 tax increases for the General Assembly to consider in its 1988 session, state officials took a page from some Northern Virginia jurisidictions, notably Fairfax County, that have tried a variety of innovative financing schemes to keep that region's transportation network abreast of record development.

"This is our textbook," Finance Secretary Stuart W. Connock said as he riffled through the pages of tax options that he and others presented here to a special Commission on Transportation in the 21st Century.

Connock stressed that the 18 measures, ranging from higher boat-docking fees to as many as three distinct sales tax increases, were only first steps in the second chapter of a transportation inititative that will generate $1 billion a year for roads in the next decade.

Last September, following the recommendations of the transit commission appointed by Gov. Gerald L. Baliles, the General Assembly raised several statewide taxes and fees to pay for dozens of new highway projects. Having addressed transportation from a statewide perspective, the next logical step is to grant taxing authority to those communities that need it for local projects, officials suggested today.

"To take just the September session would have been a Band-Aid approach," said state Transportation Secretary Vivian E. Watts. "The emphasis now has to be local option, local option, local option."

Although Northern Virginia has taken the lead in local highway financing with the Dulles Airport toll road, a regional 2 percent tax on wholesale gasoline prices and special transportation districts to pay for road widenings, other congested locales have not been granted such powers by the General Assembly.

Chesterfield County, a booming jurisdiction outside Richmond, and Virginia Beach, the most populous city in the state, are among those needing new sources of transit money, officials said.