Conversation so far:
What environmental issues is Michael Bloomberg concerned about?
Bloomberg unveiled PlaNYC: A Greener, Greater New York on April 22, 2007, to fight global warming, protect the environment and prepare for the projected 1 million additional people.
What did Michael Bloomberg do about the Global Warming issue ?
During his second term as the mayor of New York City, Bloomberg unveiled PlaNYC: A Greener, Greater New York on April 22, 2007, to fight global warming.
Did Michael take any actions of other environmental issues besides attempting to address the global warming issue?
In October 2007, Michael Bloomberg launched the Million Trees NYC initiative, which aimed to plant and care for one million trees throughout the city in the next decade.
Was the Million Trees Initiative started by Michael Bloomberg successful?
In November 2015, New York City planted its one millionth tree, two years ahead of the original 10-year schedule.

Question: What initiative did Bloomberg take to prepare for the additional 1 million influx of people?
Self-contained rewrite: What initiative did Michael Bloomberg take to prepare for the additional one million influx of people to New York City?