Guest Blog by Anthony Avery, Bike and Pedestrian Coordinator, City of Aurora
Figure 1 - Aurora City Center Land Use Map
Cities have required a minimum number of off-street parking spaces generally since the Second World War. While researchers don’t know where the implementation of the first minimum parking requirement occurred, the earliest I found for Aurora established minimums in the zoning code in 1969. So when we started performing research for our code re-write it was a given that minimum parking requirements would continue.
As planners we have a status quo and a vocal community saying we need a large amount of off-street parking, and that the city should be the ones requiring developers to build enough parking. The easy thing to do would be to maintain our current minimum parking standards and focus on more controversial issues. But I was curious: How useful are our current minimum requirements? I began with a premise that most parking in Aurora consists of surface parking lots, these spaces take up a lot of space, and they cost money to build and maintain. According to Tod Litman of the Victoria Transport Policy Institute, the average surface parking space costs $19,700 in 1997 dollars; adjusted for inflation to 2015 dollars this total is $29,292, or roughly $102 per month. If we require a 6,500 square foot restaurant to meet our current zoning code requirements, they would be required to provide approximately 70 parking spaces at an estimated cost of $7,140 per month.
In many cities there is more space required to provide parking than can be utilized for generating commerce. A 250,000 square foot shopping center in Aurora will require 950 parking spaces. At an average size of 320 square feet per space, 304,000 square feet will be dedicated to parking vehicles, or 21% more space than is provided for shopping if provided as a surface lot. Aggregated over a large area, it becomes easy to see how minimum parking requirements can spread destinations apart. In the City Center area of Aurora, Target and the Town Center at Aurora are often considered to be next to each other, but in reality are almost ½ mile from door to door. The yellow in Figure 1 (top) is parking. In what is supposed to be Aurora’s Downtown, surface parking consumes approximately 27% of the land area. Other land uses depicted in Figure 1 include streets (red, 20.6%), undeveloped land (blue, 10.1%), and open space (green, 9.1%), leaving approximately 33.8% of land to generate commerce or providing housing.
Because of the land area and financial costs of requiring parking in our city, it behooves us to make certain we’re efficient in our requirements. Historically, many cities have simply copied what other cities have done or relied on ITE estimates which are wildly inconsistent or insufficiently accurate. While evaluating commercial parking need is expensive and time consuming, evaluting residential parking proved to be much easier.
The U.S. Census provides detailed information on the number and type of housing units in our city, and detailed vehicle information by household. Using this Census data, and applying our code’s minimum residential parking requirements to it, I’ve estimated we require 426,576 parking spaces (including guest spaces) for all housing in a city with approximately 360,000 people. In addition to off-street requirements, but not included in this estimate, all local streets in Aurora have been designed to allow for on-street parking. In a typical single-family detached environment, this equates to between one and two on-street spaces between driveways in addition to the four spaces required on-site. According to Census data, Aurorans own approximately 211,156 vehicles. If we were to allow on-street parking to satisfy guest parking requirements and eliminated all the excess off-street parking throughout the city, over $6 Billion in construction and land costs and 1,221 acres of land could be re-couped saving the average household $170 per month in housing costs.
Looking at the aggregate is impactful, but we can take even more meaning from the discrepency between the housing in our city and actual vehicle ownership. According to the Census information, and applying our current minimum requirements, we see that 83% of all housing in Aurora requires two or more parking spaces while 56% of households actually own two or more vehicles (99.1% of housing requires 1.5 spaces per dwelling unit plus guest parking).
Figure 2 - Household Vehicle Availability vs. Required Parking
If we’re already requiring twice as many residential parking spaces as needed, what is going to happen when our neighborhoods start to embrace the sharing economy, our new light rail line, or increased density in strategic areas allows more trips to be taken by foot or by bike? With Aurora-specific data that supports an immediate and drastic reduction of parking minimums we need to be concise in our response. With the prospect of a reduced need for parking due to autonomous cars and/or an increased sharing economy, we have to be flexible. Many of our new zones will still have parking minimums, but in most instances we are recommending slashing requirements in half and allowing further reductions in proximity to high frequency transit and providing space for shared vehicles or bicycle parking. While we are not proposing hard maximums (some districts have recommended maximums for surface parking, but not for structured parking), we hope that by reducing our minimum requirements we can allow the market to determine an appropriate amount of parking and offer flexibility to homeowners and multifamily developers to be more efficient with their property to meet their actual needs.
Disclaimer: Anthony Avery works for the City of Aurora and has presented his information and recommendation for implementation. This recommendation does not reflect current policy or code implementation, and the proposed zoning code with parking requirements inspired by this research is currently under public review and subject to City Council approval.