For the first time in more than a quarter-century, NYC opened a brand-new subway station Sunday. The $2 billion project extends the No. 7 line to 34th Street and 11th Avenue, and paves the way for development at Hudson Yards.

The expansion of the system, including ultimately opening the Second Avenue Subway line, is critical to NYC's future, and this is the first step. But the MTA must also take care of its existing stations. A recent report from the Citizens Budget Commission said it would take more than 50 years of repairs for all current stations to be in good shape.

The subway system's needs go beyond chipped paint and broken tiles, or even platforms that can't accommodate the crowds. Current stations need wheelchair accessibility, where possible, and elevated lines need noise mitigation to accommodate the neighborhoods around them.

But those needs shouldn't come at the expense of expansion. If MTA officials can walk and chew gum at the same time, then they can expand and rehab simultaneously, too.

That effort should start with both city and state finally funding the MTA's capital plan. But far more creative and thoughtful solutions are needed. The key lies in thinking differently about economic and real estate development, and focusing on public-private partnerships.

In the case of Hudson Yards, the city used bonds to finance the subway project, and agreed to use the site's property tax revenue and fees to repay that debt, in a strategy known as "value capture." That's a good start, but developers desperate to build across NYC must do more.

The Midtown East zoning, and developer SL Green's deal to build the 1,400-foot One Vanderbilt next to Grand Central Terminal, should serve as a model. SL Green will make $220 million in transit improvements, including better platforms, entrances, and underground hallways and plazas among buildings, subway and rail lines. The building can't be fully occupied until that's done.

Strike deals like that across NYC. Why should developers in hot new neighborhoods build without providing for transit? Think creatively. Then, celebrate the new and fix up the old -- all at the same time.