Besides surface streets, the main urban infrastructure supporting bike ridership is a well maintained bike-lane network. The quality of bike lanes has an enormous impact in bike ridership. Lack of suspension in most bikes make them more susceptible to imperfections in the road. At the same time, bike damage, such as a flat tire or uneven wheels, can be linked to poor road conditions. City governments interested in fostering bike ridership as a mode of transportation should also ensure an effective infrastructure maintenance program.
However, this maintenance creates a set of problems for city governments around resource allocation constraints. The challenge therefore, is to come up with a cost-effective way of performing citywide bike-lane maintenance. A key aspect of this is to detect which bike-lanes need maintenance more than others. While there exist techniques to solve this problem, they are often are time intensive and costly that do not allow cities to perform routine bike-lane quality surveys. We argue that these surveys should be audited frequently for cities to be proactive around maintenance and avoid the large costs of deferred maintenance.
Our SQUID-Bike solution is a new standardized measure of the general condition of a city-wide bike lane infrastructure by integrating digital street imagery and ride quality data using readily available, inexpensive, and open source technologies. Our approach enables municipal agencies to answer a simple question: Which bike lanes are worse off than others in a municipality? This empowers agencies to engage in a proactive and equitable maintenance program by relying on digital assessments of all bike lanes in a city. Using frequently updated, longitudinal data from SQUID-bike would allow municipality agencies to observe bike lane degradation over time and could be used to power an anticipatory maintenance program and avoid the huge financial and political burdens of deferred maintenance.
Literature review and related previous work
Cycling (along with walking) are considered to be “the most economically, socially, and environmentally sustainable forms of human locomotion”.\cite{rudinger_social_2005} The literature shows that the introduction of a bike-lanes causes increase of bike ridership, ranging from +21% up to +171% \cite{monsere_lessons_2014}. At the same time, in city centers a trip made by bike can take less time than using a car \cite{Faghih_Imani_2017}. Furthermore, studies measuring street volume capacity show that the number of people who can be transported in a 3.5 m wide lane per hour on a bike ranks third most after trains and walking: bikes are able to move over 14,000 people, with trains moving 22,000 and walking able to handle 19,000 people. All of these rank above buses and cars, which are able to only accommodate 9,000 and 2,000 people, respectively \cite{botma_traffic_1991}.