Editorial: Let's help East Midtown have a growth spurt

What's the secret to New York's dynamism? Here's one element. For more than 400 years, the city has reinvented itself as economic circumstances demand. So we're delighted that the dramatic rezoning plan for a dozen or so new state-of-the-art office towers around Grand Central Terminal is gaining momentum.

The need for an upgrade is undeniable. The average age of the neighborhood's office-building stock is more than 70 years. That's a worrisome figure at a time when many large companies are insisting on wide-open floor plans in structures fully wired to handle cutting-edge electronics.

Without an intensive infusion of construction in East Midtown, companies could start looking elsewhere for space -- which might tip America's largest central business district, and the city, into a painful decline.

It's imperative to move fast on the city's request. But it's also imperative to settle some major questions before we cast these plans into concrete.

What about transit? The city is defining East Midtown as the area between Second and Fifth avenues and 39th and 57th streets. Its north-south subway spine -- the No. 4, 5 and 6 trains on the Lexington Avenue line -- is the only such service on the East Side, carrying an average of 1.3 million riders daily. It is painfully packed already, and the Long Island Rail Road is scheduled to start delivering 160,000 more passengers daily into Grand Central in 2019. The Second Avenue subway will offer relief. But its first phase, from 96th Street to 63rd Street, won't be ready until 2016. And the 63rd-to-Houston Street phase doesn't even have an ETA. The question for City Hall is: Will the Second Avenue subway be rolling through midtown in time to handle the East Midtown boom? It had better be.

What about street life? It's not enough to pack people into towers reaching to the heavens. What assurances do we have that East Midtown won't be cast into gloomy shadows? What assurances do we have that the streets will bloom with parks and other places where workers and residents will want to linger and savor urban life? Midtown must grow -- but not at the expense of its quality of life.