Former NYC official urges cities to consider how they manage resources

Density is an important element of a strategy for city's development. That's a lesson Daniel Doctoroff, former deputy mayor of New York City and now chief executive officer of Bloomberg LP, told his Chinese counterparts.

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"One of the mistakes many cities make and now have to pay the price for it, is spreading things out too far," he told China Daily. "From an environmental perspective, there is nothing better than density. You use far less energy, far fewer cars, which is why in New York City carbon emissions per capita are one-quarter of that of rest of the United States."

Moreover, "density provides a feeling of a vibrant city", according to Doctoroff, who once oversaw the densest city district in the world, Manhattan. But he also noted that "density" is a thing that has to be managed very effectively. He particularly stressed that in environmental terms and for quality of life, it is "essential" to concentrate resources along the mass transit system.

He also attached great importance to city planning in terms of "managing density". For example, the New York City government never told owners of a property what they had to build.

"What we said is here is an area of the city, it's going to serve a certain purpose. There are permissible heights, park access issues and many other things that you have to fulfill. But beyond that, it's your choice," he said.

A landmark legacy Doctoroff left to New York City, which also illustrates the importance of "planning", is PlaNYC, a 127-point plan designed to create an environmentally sustainable 21st century city.

The plan focuses on every facet of the city's physical environment - its transportation network, housing stock, land and park systems, energy network, water supply and air quality - and sets the course for a 30 percent reduction in global warming emissions by 2030.

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