Legend Explanations

Traffic Interaction Levels – these levels were developed using the Bicycle Level of Service (BLOS) formula.  This formula measures the level of comfort the average cyclist will feel on a roadway given the conditions of pavement width, traffic volume, motor vehicle speeds, pavement quality, the percentage of large trucks, the presence of a bike lane or paved shoulder, and the presence of parked cars.  This formula is weighted toward the conditions found during rush hour, so it will not necessarily reflect what you would experience on, say, a Sunday morning.  This formula also does not reflect the existence of sidewalks or paths next to the roadway.

The BLOS formula ranks roadways with grades of “A” through “F,” just like the grades you received in school (except that it includes an “E”).  We have simplified the scale to reflect “low” (green; A & B), “medium” (orange; C & D) and “high” (red; E & F) levels of interaction with motorists. 

Low Interaction (Green; A & B) – these roadways generally have slower motor vehicle speeds, lower motor vehicle volumes, smoother pavement, or may have a little-used parking lane or a bike lane.

Medium Interaction (Orange; C & D) – these roadways may have bike lanes or wide curb lanes, or may have low enough traffic volumes to provide a modest level of comfort.

High Interaction (Red; E & F) – these roadways will have some combination of narrow lanes, high motor vehicle speeds and volumes, a high percentage of large trucks, and/or very poor pavement.  Some may have bike lanes or paved shoulders.

IMPORTANT: The BLOS formula does not measure the safety of a roadway for bicycling.  Your safety is based primarily on how you drive your bicycle and how the motorists around you behave.  Also, be aware that conditions will inevitably change on many of the roadways rated on this map.  Traffic volumes increase, roads are widened, bike lanes and paved shoulders are added, and pavement can deteriorate or be resurfaced.  Most of the data for this map was collected during 2007 and 2008.  The formula also does not address conditions at intersections.

Designated Bicycle Lane – a lane on the roadway at least four feet wide designated with a bicycle symbol, arrow and/or diamond.

Undesignated Bicycle Lane – the lanes are striped in the same manner as designated bicycle lanes, but without the bicycle symbol or associated signs.

Paved Shoulders – on roadways without curbs, these roadways have a paved shoulder at least four feet in width.

Door Zone Bicycle Lane – a designated bicycle lane next to on-street parking which is not wide enough for a cyclist to stay out of the path of opening car doors without leaving the bike lane.  Bicyclists should always keep at least four feet to the left of parked cars.

Under Construction – a roadway under construction which will include designated bicycle lanes when completed.

Wide Curb Lanes – on these roadways the right-most through lane is 14 feet or wider.  Such lanes are normally wide enough to be safely shared by motorists and bicyclists and have essentially the same safety performance as bicycle lanes.

Trails – paved paths at least 8 feet in width shared between bicyclists, pedestrians and skaters.

The map shows:

· Existing Trails

· Future – Funded: those with dedicated funding expected to be constructed in the next 5 years

· Future – Prioritized: trails in line for federal funding, but more than 5 years in the future

Overpasses and Underpasses – this layer includes overpasses, underpasses and tunnels; not all are associated with trails.

Short Connector Paths – these are very short paths which provide connections between local streets, major roads, and longer paths.

Local Street Connections – routes on low-traffic local streets developed by local bicycling clubs.  These streets do not have any special bicycling accommodation.

About Sidewalks – Sidewalks are not indicated on this map, except in cases where trails run alongside roadways.  Although these ratings are for on-road conditions, bicyclists using the sidewalk can expect similar increases in the amount of interaction with traffic.  In general, driving a bicycle on the sidewalk does not decrease the risk of getting involved in a bicycle/motor vehicle crash, and in many circumstances it actually increases the risk.