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Sustainability in Chicago

The City of Chicago has designed a plan to increase sustainability.

As urban areas continue to grow, the question of sustainability becomes a concern. Are our cities sustainable? Currently, urban areas are centers for pollution, however they do have the potential to improve their environment impact and become more sustainable.

The City of Chicago believes that they have the potential to increase their sustainability by making gradual changes. Their Urban Design plan was developed in 2007 to improve all exterior surfaces of the city through a series of policies and ordinance recommendations.

The committee that developed the Urban Design plan recognized that the city had 60% impervious surfaces.  High percentages of impervious surfaces over an area creates a variety of problems, including increased stormwater runoff during rainfall events. The sewers pipelines of Chicago are a combined system that contains both stormwater and other waste water from the city; the pipes direct this water to the waste water treatment plant. During periods of intense rainfall, the system becomes overwhelmed and large amounts of untreated water are forced into the Chicago River, greatly increasing pollution. To address this problem, one of the city’s goals is to reduce the amount of stormwater entering the sewer systems. To do this, some surfaces were re-paved with permeable pavement that allows water to filter through the material into the ground instead of running off. Rooftops covered in gardens also allows water to seep into the soil instead of running off the roof. Both of these designs decrease the amount of stormwater in the sewer system, and help to either recharge groundwater or water plants.

Chicago’s permeable pavement allows water to drain through the material and into the soil beneath.

Green rooftops also serve to decrease the temperatures of the roof to save on energy for cooling. The high levels of heat generated by the plentiful asphalt rooftops lead to prolonged heat waves during the summer months and an increase in air pollution. Planting trees and other vegetation on rooftops throughout the city decrees the amount of heat generated, provides some shade for the building, and remove carbon dioxide from the air to improve air quality. The nutrients needed for adequate plant growth can be provided by composted landscape material that would normally be disposed of in a landfill.

Above is the green rooftop of Chicago’s City Hall.

Chicago is also trying to increase the number of public spaces to improve the city’s aesthetics and the lives of those who live in the city. The riverwalk project beautified the Chicago River, and provides a safe walking path through the city. To improve these outdoor spaces, Chicago also aspired to reduce light pollution. Cities contribute tremendous amounts of light pollution, not only is this unappealing, but it uses large amounts of energy to power all of the lights. Chicago has attempted to reduce this pollution by replacing old street lamps with energy efficient halide lamps that are brighter while producing less light pollution.

Chicago’s Riverwalk adds beauty and function to the Chicago River.

These are just a few of the ways that the City of Chicago has strived to reduce its impact on the environment. The Urban Design plan is a great way to outline some of the key issues for the city and offer real and practical solutions.