There will be locations, mostly due to ROW not being acquired, where desirable or minimum bikeway width(s) are not feasible, even after all other design criteria were analyzed as minimum values (e.g., lane widths). In these cases, it will be necessary to consider downgrading the bikeway to the next best facility type and/or to provide a parallel facility. The following should be considered when evaluating bikeway feasibility.

Meeting safety and mobility goals are typical objectives for roadway designers. Designers have an ethical obligation to provide for the health, safety, and welfare of the public, which may require a careful evaluation of mobility goals where they have the potential to degrade safety. One user’s convenience or mobility should not be prioritized over another user’s safety. Most roadway and bikeway design projects can be designed to improve safety for all modes.

As discussed in , the dimensional values of bicycle facilities influence the safety and comfort of bicyclists. The impact of the use of minimum and constrained dimensional values should be considered carefully during feasibility assessments.

When a bikeway approaches a large intersection, several decisions have to be made that can impact safety. In locations with constrained ROW, the designer may have to evaluate whether to terminate a bikeway to provide an additional travel lane or turn lane. Intersections are locations where a high percentage of bicyclist crashes occur. It is preferable to maintain the bikeway to maximize safety and comfort of bicyclists. If the bikeway cannot be continued, care should be taken to ensure the transition is clear and consideration should be given to providing bicyclists an option to leave the roadway (see for further guidance.)

Bikeways should remain consistent along a corridor. However, it may be preferable for safety reasons to increase separation as a bicycle facility approaches an intersection – for example, a shoulder could transition to bicycle lane or a bicycle lane could transition to a separated bicycle lane with a protected intersection at large intersections to minimize conflicts between motorists and bicyclists. See for information on protected intersections.

Impacts on ridership, comfort/stress, safety, and overall network connectivity should be considered when evaluating alternative bikeway designs or parallel routes to ensure the project will still meet the purpose identified at the outset. The following tradeoffs need to be considered and documented in the design process:

In instances where shared use paths or separated bike lanes are recommended by volume, speed, and/or other factors, but desirable facility widths cannot be obtained, it may still be preferable to provide separated facilities with minimum or reduced paths and/or buffer widths rather than putting bicyclists in the roadway with highspeed/volume traffic

If selecting a parallel route as the preferred route to accommodate a bikeway that meets the needs of the Interested but Concerned bicyclist occurs, the provision of alternative bicycle facilities on the desired route should still be considered to accommodate the Highly Confident design user and to provide connections for bicyclists to and from properties that exist along that desired route. A typical example would be locations where the Interested but Concerned bicyclist is accommodated on a parallel, low volume local street along a bicycle boulevard because there is not sufficient width available to provide a separated bike lane on the desired route. In these instances, the provision of a bike lane or shoulder can still be beneficial to serve the more confident bicyclists on the higher volume roadway to improve their safety and access to destinations along the roadway.