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Chicago's urban heat island street gardens

The most well-known of Chicago's greening initiatives and programs is its Green Roof program. The city led the way with the City Hall Rooftop Garden. I believe the roof garden was completed in 2000.

I really enjoy the city's the street gardens - street-tree gardens, hanging planters, and median planters - one its Urban Heat Island Mitigation strategies. According to an EPA "Smart Growth and Urban Heat Islands" factsheet, Chicago planted "over 500,000 trees" between 1991 and 1998 and by 2005, an estimated "280 miles of new median planters" were added to 120 miles of existing medians.

So what is the Urban Heat Island effect? Urban areas are warmer than their rural counterparts due to the types of surfaces prevalent in cities - asphalt pavement versus woodland. Darker surfaces not only absorb and radiate more heat, they evaporate less, and thus cooling less. In addition to hot temperatures, the urban heat island contributes to smog formation. These gardens also contribute to the city's stormwater management efforts by not creating runoff during rain events. View the classic urban heat island diagram at the Heat Island Group website.

Question: What's your city doing to deal with the urban heat island effect?


I was impressed with these street plantings when I visited Chicago in May of this year for the 2009 Garden Bloggers' Spring Fling.
Georgia said…
Chicago's greening program is very inspiring. Thanks for the photo link.

On my to-blog list is NYC's Greenstreets program.
My City just transformed an abandoned train track into a 1 1/4 miles of the newest,most fabulous park, The High Line in NYC. Visit it at
Georgia said…
Ellen, the High Line is great! I must get back to see the full summer bloom.
A. said…
mine is coming up with several 'tree parks'
Karen said…
Haven't been to Chicago since 92 so these are new to me. Great idea! In Seattle, the city has planted many trees, but not all of them make it if people forget to water them in their crucial first year. Recently, the city relaxed restrictions and permitting for parking strip gardens, so as you know I hope more folks will get into planting stuff there!