NOT WITH a bang, but with more than 300 pages of thoughts, projections and summations of the obvious, comes the long-awaited "comprehensive plan" for the future face of Washington. It leaves some important questions unanswered, and so it may disappoint the many bureaucrats, preservationists, developers and others who had expected something more definitive and conclusive from the city's planners. But there is nothing misguided or terrible in the document. It offers a peek at the city of Washington with some guidelines worth thinking about as we move toward the year 2000.

To nobody's surprise, the proposal would restrict most future commercial growth to the downtown area and most industrial development to the New York Avenue NE corridor. Other retail and office buildings would go in neighborhood and regional centers along major traffic arteries. Commercial development would not -- and here's cheer for some homeowners -- encroach on residential areas. Development of land along the 15 miles of city waterfront (along the Potomac and Anacostia rivers) would be regulated to encourage greater public access to and use of these areas.

James O. Gibson, assistant city administrator for planning and development, acknowledges that the plan skirts some highly sensitive though pertinent issues: historic preservation, specific riverfront development and permissible commercial and residential densities. These issues will undergo a lengthy and presumably hotly debated set of public hearings.

In any event, it is useful to have even a skeleton master plan, a general statement about how Washington might best grow and how at least it might be protected from the worst kinds of disorderly development. Projections of the types of jobs to be filled in the future offer some signals for educators, business leaders and would-be workers. Housing interests -- private as well as government -- can take cues from some of the plan's estimates, including one suggesting that the city's current housing supply of 227,000 units will have to be increased by 20,000 in the next 20 years to meet estimated demand. City planners also are underscoring proposals to create a surplus city land bank, to generate commercial and industrial expansion, and a semi-public economic development corporation.

The plan can yet have a real impact on what does or doesn't materialize along the streets of the city in the years ahead.