I heard somewhere that currently in many places before a road diet is implemented there is the requirement for a traffic study to take place, and the studies cost tens of thousands of dollars.

Based on all the previous road diets that have been performed, and the data from them, would it be advisable for a city (or other road authority) to simply decree something like - when repaving a 4 lane road, the default is to diet it to 3 lanes unless (... list possible reasons why diets didn't work such as but not limited to extreme traffic levels)? In other words, dieting the roads is rebuttably presumed a good idea during repaving. Such a policy would not only save money, but would also kill the anti-diet excuse of well, the traffic study would cost too much.

Speaking of which, does anyone have access to a copy of the Road Diet handbook? I would suspect that it would list the pitfalls of when NOT to road diet.

One thing that confuses me is why most municipalities feel obligated to provide free on street parking whenever they design a street. Additional road width for parking makes it more difficult to accommodate bicycles in-lane, and harder to provide good sidewalks. In a commercial area, parking should be centralized, and preferably multi level so that it does not contribute to sprawl, and allows for a more walkable environment. Within a residential area, parking for residents should be provided on the property.

https://en.wikipedia.org/wiki/Road_diet
check the sources out.
and a simple search on google there
https://www.google.com/search?hl=en&c...&aq=f&aqi=&oq=

I agree with you. If a business "needs" it's own parking then their building should be designed so that parking is provided either under or over the building. In metropolitan areas there should be parking every so many blocks. With maybe some sort of shuttle service from where the parking is to the where the shopping is. Having the people who park there parking fee cover the shuttle pass fees as well.

The shuttle pass could be used to take any shuttle to any shopping destination. And given that coding them to the location of the car is a no-brainier having a scanner that reads the cards and tells the holder where their car is parked and the shuttles to take to get back to it in the shortest amount of time.

Businesses that have parking either under or over their business can have greater control over who uses their parking areas. And if a customer parks there and wishes to leave their car there and go shopping elsewhere they could be charged extra for doing so.

The question is how much parking should each residence provide?

In the city we are getting a lot of resistance to road diets because key traffic engineers call the center lane a subside lane and not to mention an over emphases on capacity over smooth (safer) traffic flow (i.e. We need that extra lane for one mile for increased capacity even though it causes a lot of accidents as people try and jump the cue.)

Personally I have no faith in traffic studies that try and predict the end result of a change as there is a very complex list of behaviors and results (What's the goal? To get more cars through on a short light cycle, increase travel speed, reduce accidents, accommodate all users?) I would love to see more trial of designs and compare actual before and after numbers.

IIRC one of the key arguments in favor of 4-3 road diets is that road capacity is typically not affected substantially, since the turning vehicles are moved "out of the way," allowing through traffic to proceed. There are a bunch of safety enhancements too, although I will note that some more recent studies have shown a not insignificant number of head-on crashes in the center turn lane, so there is some movement toward not having the center turn lane extend too far. IMHO the goal ought to be always to make the street good for ALL people, be they cyclists, motorists, freight drivers, pedestrians, and so on.