MANHATTAN’S street grid, which turned 200 years old last month, has long been an easy target for urban romantics. They love to point out how its relentless logic — most blocks are a precise 200 feet by 600 feet — imposed a soulless Cartesian order on a once-lush coastal island, trampling nature and leading to two centuries of real-estate mania.
But the Commissioners’ Plan, as the grid is formally called, in fact made prescient and wise use of the city’s natural environment — a fact that was lost on later generations of city planners. As the Bloomberg administration looks for cost-effective ways to make New York more resilient to the effects of climate change, it should look back to the grid’s genius and find new ways to help, rather than stifle, the constructive role nature can play in shaping the city.
Manhattan’s natural resources were a major reason that Native Americans, and then the Dutch, settled here: the soil is easy to dig, the drinking water is excellent and the soft ocean breezes and startling vistas make it a pleasant place to live.
The early 19th-century planners who created the grid knew how to make the most of these attributes. They laid out the grid so that the sun sets precisely in line with east-west streets several times a year. The short north-south blocks mean more streets lead to the rivers, allowing floodwaters to recede easily and drawing people to the waterfront. The plan guided raucous commerce along the route of an old canal and enticed future developers with the promise of sites on hills with enviable views north.
Within the grid they placed an engineering marvel, the Croton Aqueduct and Reservoir; the latter is gone, but the aqueduct still delivers clean and tasty drinking water from upstate. Perhaps their wisest move was to conserve 843 prime acres as a Central Park to provide “the lungs of the city.”
But rather than continue working with nature as a template, subsequent generations fought against the city’s environment. Planners wrangled natural streams into (eventually) rusty pipe systems. The city dredged so many swamps and poured so much asphalt that the ground has become unable to handle heavy downpours. When it rains a lot — as it increasingly has in recent years — rainwater flows into the same pipes that carry sewage. When those pipes overflow, the combined liquid dumps into the rivers. That’s not how nature would manage things.
Of course, nature hasn’t gone away. In fact, it is steadily wearing away at our efforts to control and repress it. Eight million gallons of water a day accumulate in the subway system’s underground network, and the Metropolitan Transportation Authority has to spend a small fortune pumping it out.
And, as we’ve seen, without marshlands or big patches of soil into which it can seep, snow hangs around on side streets for weeks and then converts to pothole-making muck.
Fortunately, it’s not too late to go back to the spirit of 1811. The Bloomberg administration recently created a $1.5 billion “green infrastructure” plan to replace aging public works with nature-centered projects, like distributing free barrels to collect rainwater for outer-borough gardens. It is helping to finance a 774-apartment project near the Gowanus Canal that works with the site’s natural slope by clustering buildings where ground is highest and creating a park to sop up stormwater near the shore. And it has issued a grant for “bioswales” — natural clusters of plants — in strategic places around the city to handle rainwater on the side streets.
But the city must do a lot more. To rekindle the progressive spark of the Commissioners’ Plan, the government can show the real estate value of following nature’s cues. It can tap into the Welikia Project, an effort by Eric Sanderson, a biologist, to map the whole city as it existed in 1609, to provide data about how much solar power and water absorption a site would have if you left it alone, and then offer financial incentives to developers who take advantage of those assets.
Moreover, the city should extend development at the waterfronts into the water, for example by incorporating marshland into riverside parks (Brooklyn Bridge Park already has plans to include such a feature). The city could also reopen long-buried streams — several of which still flow beneath downtown streets — that now present regular flooding hazards, a step already being tested in San Francisco.
It can require new projects to use green roofs and plantings rather than pipes to absorb stormwater, and it can give bonuses to owners who use microbes to handle wastewater.
Finally, the administration should rezone the city into “eco-districts,” areas that share topography, microclimates, soil and species rather than census data. Such local attention is critical to steps like switching to renewable energy — after all, relying on tidal power makes more sense on eastern Staten Island than in central Brooklyn, where wind power might be a better option.
Sound wild? No wilder than laying out 155th Street in 1811, a time when Union Square, nearly seven miles south, was still a hill full of oak trees. The street grid made real estate speculation seem as natural to Manhattan as bedrock. With pressing needs for better housing and public health, and an imperative to provide it in an ecologically intelligent way, we should let nature once again teach us where and how to grow.
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