Safety and Costs of Bike Lanes

Home » Safety and Costs of Bike Lanes

Last week the city council passed Resolution #31826 committing the city to completing certain pieces of the downtown bike network in the next 18 months. I expect the City’s Department of Transportation to do their best work in identifying cost efficiencies as they finalize designs for these projects so that we can get the safety improvements as affordably as possible.  I will be continually monitoring their work to ensure this occurs.

I also recognize that certain improvements may come with significant costs because of the existing road design or other existing deficiencies that will need to be addressed.  In these instances, if the project is still the best solution to address safety needs, I will also support these projects. It is important that we not sacrifice the safety of some people simply to save money and we must also be aware that sometimes the cost of doing nothing can be significantly more than a safety investment.

This challenge has recently come to light as the city opened a couple of new protected bike lanes in downtown Seattle:

  • On 2nd Avenue, the city spent nearly $11 million to extend the existing protected bike lane from Pike St to Denny Ave.
  • On 7th Avenue the city spent $3.8 million to build a protected bike lane from Westlake to Pike Street.

A breakdown of some of the costs were detailed in the Seattle Times two months ago.

This has raised questions such as why some bike lanes cost as much as they do and what is the appropriate amount to invest in safety projects for various roadway users. I want to address both of these questions.

First, why are some safety projects so expensive? The context in which we make safety investments plays a huge role in how expensive the projects are. For decades our road system has been designed to move cars, often at the detriment of other road users, and the cost to retrofit that system can be expensive in some circumstances.  In the case of 2nd Avenue, to make that roadway function for all users required a complete upgrade to the traffic signal system that was decades old and in need of being replaced at some point regardless of this project. Forty percent of the project costs were to cover the signal replacement which was mostly to manage car traffic.  When safety projects require broader system upgrades that would ultimately be necessary regardless, it can make those safety projects look more expensive than they would otherwise be.

An alternative example to this are the safety investments made along Pike and Pine streets between 2ndt Ave and 7th Ave.  Because modern signal infrastructure was already in place and the existing curb infrastructure could accommodate the safety improvements, SDOT was able to install 7 blocks of protected bike lanes in 2017 for only $325,000.

Sometimes decisions that are not directly related to the safety improvement have a cost impact on the project.  For example, on Second Avenue, a decision was made to minimize the disruption to Pike Place Market during the summer months by not partially tearing up that road to determine the exact location of other infrastructure.  This was an intentional and well considered decision and it resulted in greater costs to the safety project.

The second question I field in my office is also a fair one: what is the appropriate amount to spend on safety improvements?  We need to be smart and thoughtful about what are the appropriate investments to make at this time, but it is also critical that we make significant strides to meeting our Vision Zero goals  to eliminate all traffic deaths and serious injuries by 2030.  We have a comprehensive strategy to achieve this goal that includes investment in roadway infrastructure to ensure safety for all road users. In some cases we can make low cost investments that deliver the necessary safety improvements, like we were able to do on Pike and Pine streets.  Other times there are significant costs to make the necessary safety improvements, such as was the case on 2nd Ave.

Above all, it is also important to recognize that there can be significant costs to not making necessary safety improvements.  In the case of 2nd Ave., a cyclists and new mother, Sher Kung, was struck and killed four years ago while biking. The city paid a $3.1 million settlement in that death, but the incalculable loss to her family and community goes far beyond dollars.

As we work to make investments so that all road users are safe, we need to be smart in finding the most cost-effective ways to deliver the necessary safety improvements and in some locations there will be projects where it will require significant investments to correct a design that is inherently dangerous.  To meet our Vision Zero goals, I will continue to support safety improvements for all users.