Road Diet - Lane Width Details

Josh Thede

Our community successfully advocated for a 4 to 3 lane road diet and it's approved by council and will be repainted soon during standard maintenance and UBAS treatment. Huge win for walkability in our city! Now to get the details right.

Existing: all 4 lanes are 10 feet wide and there is angle parking on both sides, they've said bike lanes aren't a good idea due to the parked cars backing up.

Question: What should the lane widths be for each of the 3 lanes? If I understand correctly design consultant is recommending 12' / 14' / 12'. . . Is 10' / 10' / 10' acceptable for a road diet? As an pedestrian advocate and strongtowns advocate skinnier seems much better for pedestrian crossing distance.  



  • Comment author
    Daniel Ullfig

    I strongly support the idea of liable towns. But I would put "road diets" in the "anti-car" category. Making it harder to use your car is just agravating, if you still have no option to buy your groceries than to get in your car and drive to the supermarket. If you build a city that has stores within walking distance, you won't need to force people out of their cars.

  • Comment author
    Christopher Grgich

    Hi!  I think Road Diets are a great way to slow vehicle speeds. Congestion can also cause vehicles to travel at a safer speed. 

    I would actually start by asking what speed the engineer's are designing the corridor to handle. 12-foot wide are pretty typical of speed higher than 35 mph. For speeds around 25 mph, and especially where existing lane widths are 10-feet, I would not recommend widening the lanes. Wider lanes basically mean more speed, and I would not recommended higher speeds mixed with cars backing in from the adjacent parking. If there's transit on the corridor, I would default to 11ft width throughout, however if not, I would push for 10-11-10 foot lanes, to match the existing lane widths and help slow traffic through the corridor. 

    If striping a bike lane feels unsafe to the designers, I'd press and ask where bikes will be allowed to exist? Not striping the lane does not mean there willbe no bikers, instead it just pushes the liability for biking to the user, and that's not acceptable. Existing should not be a liability for any user. If speeds are sufficiently slowed, can sharrows be deployed? Can a bike facility be provided on the other side of the parking, or behind the curb? SImply not striping a bike lane because it's unsafe, doesn't actually provide any safety for non-vehicle users. 

  • Comment author
    Robert Volpe

    Yes.  10' / 11' / 10'.  The suggested 12'/14'/12' is way too wide and will encourage speeding through the area.


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