Protected bike lane retrofit via lane removal
RFT-CDR-08 CorridorProtected bike lane retrofit via lane removal
Overview
Where narrowing lanes alone doesn't recover enough width for a genuine protected facility, removing a full travel lane does. This is effectively a road diet whose primary purpose, rather than a secondary benefit, is the bike lane it creates. AASHTO recommends this approach specifically where a corridor's traffic volume can absorb the reduced through capacity.
Related Media
The items below come from outside the Commonway System, external videos, podcasts, and articles related to this page's topic, not part of the guidebook itself.
Are Streets Too Complicated Now?
Asks whether today's proliferation of lines, signals, and lane types on streets is overcomplication or a needed response to modern demands, a question that runs directly through CS's Element-scale catalog and the density-tiered Corridor retrofit paths this video is tagged to.
Dutch-style intersection design: bike-friendly
Shows the protected-intersection design vocabulary, continuous cycle tracks, corner refuge islands, separated signal phasing, that underpins CS's Protected Intersection pattern and the Corridor retrofit paths built around it.
Where this leads: Target patterns
Bike Highway / Greenway (COL-BHG-04), Default (No Parking, No Direct Access) (ART-DEF-01) with Protected Bike Lane / Cycle Track (ELM-PBL-37)
Applicability and thresholds
Follows the same volume thresholds as a standard road diet, since removing a lane carries the same through-capacity implications regardless of what the recovered space becomes. Most viable below roughly 19,000 to 25,000 vehicles per day.
Evidence and effectiveness
FHWA reports crash reductions of up to 29 percent on road diet conversions generally; where the recovered lane specifically becomes a protected bike lane, the same crash-reduction mechanism applies alongside the added bicycling safety benefit of physical separation from traffic.12
Getting it built
Can move through the construction spectrum the same way a standard road diet does, restriping first, with a protected lane's physical separation elements (curbs, planters, or flexible posts) added at the quick-build stage before permanent construction. See Construction Methodology & The Build Spectrum.
Who can move this
Usually a city or county transportation department decision, following the same approval path as a standard road diet. See Legal & Planning Mechanisms.
Related retrofit strategies
Protected bike lane retrofit via lane-width reallocation (RFT-CDR-07), Protected bike lane retrofit via parking reduction (RFT-CDR-09) (the other two approaches to the same underlying goal, distinguished by where the recovered width comes from)
References
- Evidence-based Transportation Policy Research, Texas A&M Transportation Institute, "Bicycle Lanes." AASHTO-recommended retrofit approaches without widening the road.
- Legal / regulatory Federal Highway Administration, "Road Diets (Roadway Reconfiguration)," Proven Safety Countermeasures, FHWA-SA-12-013.