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Induced Traffic Myth

Here's what happens. They widen the freeway. Developers see that people are content to live in the suburbs with their cheaper detached house and now a reasonable commute. They subsequently over-develop (not just "around" the freeway) with no restrictions from local government's Planning. And in about 5 to 8 years the freeway is as congested again.

So everyone immediately blames the larger freeway as the reason why there is more development !
In fact, of course, the direct reason for freeway congestion is the indiscriminate approval of development by the governments; "induced traffic" . Planners disregarding traffic instead of using it as an environmental disqualification of new development.

So the DIRECT solution to freeway congestion is to RESTRICT DEVELOPMENT where traffic is already congested.
We need Environmental Impact Reports to rigorously include restrictions on development where freeway capacity is insufficient.

We need to ensure freeway congestion does not return only 5 to 8 years after freeway expansion. Returning because Government Planning is not  prioritizing freeway expansion over rail AND uncontrolled development.

You see, freeway expansion not only improves auto commuting but bus commuting. Bus Rapid Transit systems have lower capital costs than Light Rail systems and provide similar performance with more flexible routing.

Politicians rather than "knee-jerking" simplistic, "popular" projects must instead consult objective Research Groups and Academics that have studied the impacts transport has made on our society, quality of life, and environment. Otherwise we waste hard to garner public money that should instead be directed to cost effective projects benefiting the maximum number of people as well as providing the greatest improvement in our environment (a solution that may not be so obviously seen by most).

A pragmatic Solution to Overdevelopment might be that developers must contribute proportionally to a COSTED, PLANNED, SCHEDULED, multi-county FREEWAY EXPANSION fund. This might deter development where it would not, as a result, be so profitable. 
Where freeway expansion is not "multi-countywide-PLANNED" (for whatever reason, maybe voter related) then NO DEVELOPMENT would be allowed at all. Planning has to include maintaining freeway at a Level of Service C (not D as it is now).
"I know, hard to sell and hard to implement". It would require that one county should not develop if it were to affect traffic in another. But what else?

Puncturing the myth of "more roads mean more congestion"

Induced Traffic  -  the definition:- Some who now carpool would choose to travel alone, some who now travel on parallel routes would travel on the freeway instead, some who now travel earlier or later would revert to traveling at a more convenient time, some who ride the bus will choose to drive a car, and some who do not travel the route at all will be induced to travel on the newly freed-up road.
And all who do this were struggling to get to work in the first place. And Boy! does that prove how much the freeway expansion was needed. But their effect on congestion is negligible compared to the induced traffic from over-development. There are many examples, of course, where freeway expansion works.

The Sierra Club are re-evaluating their philosophy on Transit. (quote:- "Building Roads Doesn't Solve Congestion")
"our analysis disclosed that deterioration in air quality has generally worked in favor of road expansion, ostensibly as a means of improving traffic flows" "Air-quality forecasting models assign benefits to higher average speeds from expedited traffic movements. "- this is a conclusion of
The vague and ambiguous study used as the "Induced Traffic Bible" .   
This study, (used to try to justify the whole concept of "Induced Traffic")  concludes that Air Pollution is LESS when roadway is increased !!! Totally reversing one of the postulated "drawbacks" of increasing roadway, espoused by the same "Induced Traffic" pontiffs.  Slower moving congested traffic creates MORE Exhaust Air Pollution than faster traffic. Running slower is more energy inefficient.

This link from the Sierra Club's site admits to Induced Traffic being caused by development over about 8 years and little to ANY OTHER causes http://sierraclub.org/sprawl/transportation/gridlock.asp

"The TRB report was inconclusive on how induced travel may effect air quality. This issue is complicated by the relationship between traffic dynamics (e.g., such as changes in acceleration characteristics) and emissions." This is the other link (page 10), from the Sierra Club's website.

 
      
      Just control my branches
You don't make a Bonsai tree by constricting its trunk.

BUT ROADS CAN'T SOLVE ALL THE PROBLEMS?

As long as 1 freeway lane (a lane each way) offers 5 times the passenger-miles of any rail system, and costs less per passenger-mile than rail, then the sensible solution is to direct traffic improvement dollars towards freeway, before rail (where it is a feasible alternative).
 


Questions?
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