EDITORIAL PLANNING FOR GROWTH MAKING A BIGGER LOS ANGELES A BETTER LOS ANGELES.

ON MONDAY, we outlined some challenges and opportunities for the new year. Critical among them was managing an ever-increasing population.

The latest census numbers tell the story: Since 1990, the state's population has increased by more than 4.1 million, including 350,000 new residents in Los Angeles, with more than 100,000 more in the Valley.

In the next 20 years, Southern California's population is expected to rise by an additional 7 million.

In a region that's already plagued by innumerable shortages - from electricity to police officers - the prospect of yet more growth is daunting.

Even now, our freeways look like parking lots, and our schools must operate on year-round schedules just to keep up with their burgeoning student bodies.

And then there's the question of where to put the region's new inhabitants. There's little room for new housing developments in L.A. In the outlying areas, land is going fast.

Dealing with the reality of a booming population is crucial to ensuring the quality of life for L.A.'s current and future residents. With intelligent management, it's a challenge the city should be able to answer - but planning is the key and it has never really been done.

To accommodate growth, local governments will need to invest time, effort and capital into bolstering the region's infrastructure: building new schools and power plants, widening freeways, and expanding mass transit. They will also need to adhere to the city's long-term growth plan, instead of casually granting exemptions to anyone who asks.

More importantly, city leaders must abandon their obsession with making all of L.A. revolve around downtown. The best way to ease the problems of urban congestion is to realize that L.A. isn't one city at all - it's a hodgepodge of many small cities, each with its own needs.

Decentralization is crucial.

That applies not only to mammoth bureaucracies like the Metropolitan Transportation Authority and the Los Angeles Unified School District, but also to the neighborhood councils, which should be empowered to make decisions in matters of public policy.

For too long, the city's downtown power structure has paid little heed to the interests of the San Fernando Valley. But the importance of the area - as the population mounts - cannot be overstated.

To borrow from a popular phrase, meeting the demands of a growing Los Angeles will require city planners to think regionally, act locally. Regional authorities need to set the game plan, and local governments must have the discretion to work out the details.

The numbers are clear - without careful planning, L.A. is set for a troubled future. But under the right conditions, our city can get bigger and it also can get better.