Last October, Mayor Emanuel broke ground for 312 RiverRun, a project connecting four North Side neighborhoods and three parks with nearly two miles of new bike and pedestrian paths along the riverfront.

The mayor used the occasion to call for “a new plan” for the city’s parks, and he invoked Daniel Burnham — he of no little plans — as his inspiration to “use our river and lake to better connect communities and enhance residents’ quality of life.”

Chicago has a golden opportunity now to make good on that call. In the true spirit of Burnham, City Hall should embrace a proposal to carve a 24-acre public riverfront park out of the 760-acre North Branch Industrial Corridor area.

The North Branch Park & Nature Preserve Alliance, a coalition led by two North Side aldermen — Michele Smith (43rd) and Scott Waguespack (32nd) — and including an impressive list of architectural, environmental and neighborhood groups, is trying to drum up support for their idea before plans for redeveloping the area become set in stone.

The 24 acres is the last big parcel of land that remains in play, given how quickly developers began snatching up the North Branch’s 760 acres last year after it was rezoned for residential and commercial use.

Renderings of the park concept show a sparkling green jewel of nature trails, play areas, athletic fields, a boardwalk and plaza, a boat launch and more, all nestled right up to east bank of the Chicago River from North Avenue on the south to Cortland Street and the widely used 606 Trail on the north. The tens of thousands of new residents and workers expected to descend on the area surely would welcome it as a place to bike, walk, skate, play ball, picnic or simply enjoy nature.

The rest of Chicago would benefit as well. If there is one thing we love as Chicagoans, it’s our public parks.

A major riverfront park would help meet the mayor’s goal to grow that park system. We already have the Riverwalk and Chinatown’s Ping Tom Park to the south. A major new North Branch park would continue this commitment to reinventing the banks of the river, adding a large-scale recreational space on the park-scarce North Side.

Without the city’s backing, those 24 acres of prime property more than likely will be filled up with densely packed high-rises, broken up by a patchwork of modest corner gardens, tot lots and other small-scale green space to meet the open space requirements of the North Branch “framework plan.”

Small pockets of green space might be enough to satisfy developers and well-heeled condominium buyers. But they’re hardly enough in a city that aspires to be world-class and boasts the motto “Urbs in horto”: “City in a garden.”

As attractive as the idea of a new and generously large public park may be, the city has yet to do more than signal its backing for the vague concept of making open space in the area a priority. Ald. Brian Hopkins (2nd), in whose ward the park would be located, is not part of the coalition and told the Sun-Times that costs — for transit and road improvements as well as recreation — need to be controlled. (The North Branch Park coalition puts the price tag for the park — including environmental cleanup, but not the cost to buy the land from its current owner — at about $40 million.)

A spokesman for the mayor pointed to the existing framework plan, as well, and said Emanuel agrees that substantial open space is “essential.”

Truth be told, at one time we might have thought the original plan for this 24 acres — the pocket parks, sliver of a bike path and the like — was probably fine. But when aldermen Smith and Waguespack and their coalition proposed their much more ambitious park plan, we knew we would have been thinking small and not even knowing it.

Now we can’t image how Chicago can pass on this grand opportunity to create another urban jewel.

We get the nervous calculation here. City Hall is no doubt wary of scaring off developers, and much-needed tax dollars, by insisting on too much parkland. But if the history of Chicago tells us anything, it is that major parks — whether along the lakefront or out in the neighborhoods — typically enhance nearby property values and attract homebuyers and businesses.

Cost is a factor, of course. But surely some mix of private financing, developer incentives and the like could be worked out. We’ve done it before and we can do it again.

The city should embrace this new vision and run with it.

Editor’s note: The North Branch Park & Nature Preserve Alliance includes Friends of the Chicago River, a group headed by Margaret Frisbie, who is a sister of Sun-Times Editorial Board member Thomas Frisbie. Thomas Frisbie recused himself from the writing process for this editorial.

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