Cars are a necessity for many of us. They get us where we need to go. Cars also pose a set of interesting issues. As a driver and an environmentalist I tend to give a lot of thought to the environmental impact of driving a car, but I’ve never really given much thought to parking.
Parking a car creates a whole subset of issues. Parking spaces take up more space than buildings, parks, or industrial complexes. They’ve been called the single biggest land use in any city. Did you know that the US has an estimated 3-8 parking spaces for each car? That’s a lot of wasted space.
The Environmental Impact of Parking Garages
Parking garages are usually built in denser urban areas and are designed to house many cars in a relatively compact space. Because they are open-air and high-density, garages are greener than other parking modes. However, they also contribute to urban heat islands and often use a lot of electricity because of lighting-level requirements, during both day and night.
The Environmental Impact of Urban On-Street Parking
When I lived in the North End of Boston I would circle the blocks sometimes for up to a half hour looking for a spot to park my car for the night. Cruising — the practice of circling the block until a spot opens up — has serious environmental impacts. Because it can add, on average, 10.6 stop-and-go minutes (in New York City) to 11.5 minutes (in Cambridge, Mass., ibid) to the time of each journey, it increases air pollution in cities.
The Environmental Impact of Surface Lots
Think of those big lots surrounding a shopping mall or an office park-that’s a surface lot. These big, sprawling lots are guilty of something called “runoff”-they increase storm water volume and speet up to 16 times over a similarly sized meadow. Runoff not only physically reconfigures the shape and velocity of streambeds (bad for fish and vegetation), it also introduces oil, metals, and soils into waterways and prevents the recharge of aquifers (bad for our potable water supply). In large metropolitan areas, unsustainable parking lot design may be responsible for up to 132.8 billion gallons of waste water each year (enough to supply 3.6 million American households).
Also, when natural vegetation is replaced with a parking lot the asphalt retains heat and makes lots up to 30 degrees hotter. This “heat island” effect creates higher demand for air conditioning in surrounding buildings.
Light pollution is another issue created by parking lots. If you drive by a mall parking lot late at night you’ll notice the lights are still on to increase safety.
What can be done?
In a recent report released by MyParkingSign.com they found that city landscapes are changing based upon which parking signs are selling. They found that many lot owners are now looking for a diverse set of parking signs, which indicates that the public is looking for more organized parking.
The report suggests a few solutions:
Create shared parking lots. In this model, nearby buildings with different patterns of parking needs utilize a single lot. For example, offices have highest demand from 9 a.m. to 5 p.m., while residential buildings need their spaces from 5 p.m. to 8 a.m., so areas with mixed-use developments can use one lot to serve two different communities of drivers.
Redesign the lots. For example, you can hide parking lots behind buildings rather than putting them out front. Another design alternative that actually somewhat reduces the amount of asphalt is space differentiation. organizing lots to accommodate different types of vehicles , such as motorcycles (several of which could fit in a standard 18-by-9-foot space) and compact cars (which require 20 percent less space than their full-size cousins and grow ever more popular with consumers).
Here’s an infographic filled with more information on the financial and environmental impact of parking.
Do you think about parking and it’s impact on the environment?
Disclosure: I am being compensated for this post. The opinions in this post are my very own.