Chicago Alleys To Go Green

What is a green alley, you ask?  Permeable pavement.  Simple as that.  Chicago has more alleys than anywhere in the U.S.  That’s a lot of pavement.  It’s like maintaining duplicate streets.  One major problem with so much concrete is that it creates a lot of flooding because there is no where for the rainwater to go.  Its all being forced into sewers drains which creates more problems. 

The city is using permeable concrete – or porous asphalt.  It isn’t something that is used in too many places, but why not?  The alleys in the city are old and they need to repave them.  Janet Attarian, the project’s director says it best, “The question is, if you’ve got to resurface an alley anyway, can you make it do more for you?”  Exactly.  Spend more later and solve more problems. 

In addition to the rainwater solution, the alleys actually stay cooler in the summer by reflecting the sun’s heat rather than absorbing it.  Conversely, in the winter, the pavement retains heat longer.  For an added benefit, a good portion of the resurfacing of the alleys can be done using recycled construction materials. 

Lighting is also being changed.  Current street lights shine above and below and produce the all-to-familiar yellow glow.  The new lights are using metal halide lamps which give off a brighter white light and is more energy efficient.  Apparently these new “dark sky compliant” lights allow you to see colors more vividly at night. 

So far, about 46 alleys have been outfitted with the new concrete.  It’s business as usual now.  All new alley projects will be completed using the new system.  Although, I’d love to give props to Sadhu Johnston, the city’s head of the Dept of Environment, but I found this link that says the city was looking into this and completed an alley in 2001!

If you want a leisurely read, here’s the Chicago Green Alley Initiative Handbook.

Source: City of Chicago, Internation Tribune Herald