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.

Living Buildings

In 2006, the International Living Future Institute created a challenge titled “The Living Building Challenge.” The challenge was deigned to inspire long-term thinking and make room for sustainability in the modern world. There are 20 criteria that must be met  for a building to be certified as a Living Building. The broad categories that these criteria fall under are site, water, energy, health, materials, equity, and beauty. Some of the specific requirements of these buildings include a net zero energy and water consumption,  support a car free lifestyle,  constructed in a sustainable location, and integrate agriculture, even in urban settings.  Because these requirements are performance based, simply constructing a building that meets these standards does not automatically mean it has met the challenge. A year-long occupancy period is also part of the challenge, where the building must show that it can continue to meet the challenge’s standards for at least one year.

The Living Building Challenge

The high standards of sustainability required to attain certification makes a Living Building even more challenging to achieve then the current sustainability standards of Leadership in Energy and Environmental Design, or LEED certification. LEED was created in 2000 by the U.S. Green Building Council as a way of calling attention to the green potential of buildings and inspiring green construction. To become LEED certified, the building must receive a certain minimum number of points on a 100 point scale in areas of “sustainable sites, water efficiency, energy and atmosphere, materials and resources, and indoor environmental quality.” Living Building certification is endorsed by the U.S. Green Building Council as a way to take the idea of LEED a step further.

Currently, there are only three Living Building certified sites, however many more are under construction or entering the one year occupation period. There is currently  a building  under construction in Seattle, Washington that hopes to achieve Living Building certification.

Above is a rendering of what the new building will look like.

A variety of innovative ideas will be employed to allow the six story building to meet the Living Building requirements. The building  will achieve net zero energy by utilizing solar panels on the roof. The solar panels will contribute energy to the grid during the summer when the panels produce more electricity than needed. In the winter the building will have to draw energy from the grid to make up for the lack of sunlight, however the energy the building draws will be no more than it had contributed during the sunny summer months. Water equilibrium will be achieved by collecting rainwater and purifying it in an on-site facility. Water will also be circulated throughout the building as a means of temperature control to reduce the amounts of heating and cooling required.

Though the building may cost almost one third more than a conventional building, the savings in energy and water bills will more than make up for the additional cost. In addition, with the building designed to last 250 years, the savings over that time will be substantial.