PLANNING FOR A SUSTAINABLE EUROPE? - TU Berlin

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9.5.5 Reexamining the impact of ring roads on travel & land use
In order to be able to better evaluate the important objections to the M0 regarding
its future environmental risks of sprawl and increased car use, I will now take a brief look
at the state-of-the-art knowledge on the impact of ring roads on travel and land use
patterns. As already noted above, in theory, ring roads are designed to divert traffic away
from city centers in order to avoid congestion in the core. They are seen as being
beneficial both to the inner city populations who will no longer be affected by the
negative impacts of transit traffic passing through their neighborhoods, and to the road
users for whom the by-pass affords substantial time savings. Unfortunately, this
otherwise impeccable logic has two central flaws: first, it ignores the medium to longterm
effects that high-speed, limited-access ring roads have on overall land-use and travel
patterns in the region, and second, it intentionally re-locates local environmental impacts,
namely noise, air pollution and severance effects, from one location to another, thereby
pre-programming LULU 13
/ NIMBY reactions. It is the first, much more complex
problem which concerns us in this section.
The strongest general counter-argument against expanding high-speed road
capacities whenever congestion occurs is that a temporary easing of traffic conditions
will in fact induce additional travel, thus causing additional congestion in the medium to
long term. The issue remains a matter of academic dispute, although evidence in support
of this interpretation has been mounting in recent decades. At least for the case of peakhour
travel on limited access roads, Anthony Downs (1962; 1992) has by now rather
thoroughly debunked the myth that it is possible to build one’s way out of congestion.
13 Land uses perceived as detrimental to a particular area by nearby residents are often called LULUs (=
locally unwanted land uses) . What is considered a LULU varies throughout a city and also depends upon
the affluence and history of the neighborhood.