As the following four points elucidate, the protected bike path is something we need on 17th Street. We thank Mona Caron for her vision.

Mitigation. Protected bike lanes mitigate the danger to bicyclists posed by cars combined with streetcars, tracks and other traffic issues. Right now we have a lot of cars and a fair number of bikes rolling around on 17th Street. Recent years have seen both figures rising. This design change removes all bikes from this corridor’s uniquely dangerous door lanes in both directions of traffic flow consolidating them in a safe protected location off the road.

Nearby development plans and other reasons guarantee more cars on this small street. As a generic roadway management issue at some point traffic volume and dynamics necessitate separating the bikes from the cars. Considering the road condition on 17th Street, the train tracks and car dynamics that thresh hold has been crossed.

Congestion Management. This is all about mathematics. Enabling the migration from cars to bikes pulls cars off the road. A 10% reduction in private vehicles is a reasonable early projection with that figure rising to 20% and up over time. Today, these trips use cars that need parking spaces. If people chose to use bicycles, then more parking spaces would be available for those who can’t migrate to other modes of transit. Likewise, crowded buses would shed a few passengers to the bike mode.

Those gains count against the 44 spaces that the Church to Castro Street protected bike boulevard re-purposes. Ultimately every driver-turned-bicyclist past that 44th former driver represents an addition to the total parking spaces available with no upward limit. Eventually the parking supply and demand could balance better than they do today.

Getting the bikes off the street can also speed up traffic flow which can increase the efficiency of the road and its carrying capacity as well. Removing cars does not prevent others from replacing them. Thus the importance of optimization for all modes. Obviously this invokes safety issues but mitigation is key. This is a powerful benefit but with an asterix.

Economics. The pavement and surface maintenance costs of bike paths are practically zero compared to roadways carrying heavy vehicles. This reduces costs of street maintenance overall (20%) and allows said funds to be applied specifically to roadways for vehicles both public and private. How can we afford not to do this?

These small paths have extremely high carrying capacities. They can move a lot of people at the lowest cost per person possible. — Protected bike paths are associated with elevated real estate values. — Bicycling as a mode of transit has direct health benefits to the rider as it is both transportation and exercise. Growing this mode has a societal health benefit. – Protected bike lanes don’t rely on enforcement as they are structural solutions. This is a prudent approach to an expensive problem.

Environment. Every car trip generates CO2. Migrating people from cars to bikes, if only for a fraction of their overall trips lowers our collective carbon footprint. This is mandatory if our species is to survive.

The human environment benefits in numerous ways from protected bike paths. They are quiet, non-polluting and reduce the incidences of violent behavior associated with cars such as speeding, broken windows, and hit & runs.

Mona Caron’s artwork is from 300 Church Street in San Francisco. The Mural is entitled “The Market Street Railway Mural” and is copy written under creative commons attribution non-derivative, non-commercial. Mona Caron’s work can be viewed in depth at her website: MonaCaron.com.