In my last post, I introduced a question from a
correspondent about “achievable alternatives” for traffic congestion
relief. The particular question
pertained to the congested E. Washington Street in Petaluma and the proposed Rainier
Connector that many believe would provide relief, but the question could apply
to overloaded arterials everywhere.
In the
earlier post, I explained how E. Washington Street became congested. I also
presented the Rainier Connector as the apparent solution in the minds of many. Today, I’ll try to offer an explanation on
why that conventional wisdom is wrong. In
my next post, I’ll offer the alternative ways of thinking about traffic that are
provided by urbanism.
The Problem with the Proposed Solution: The reason that the Rainier Connector likely
won’t provide significant traffic relief is induced traffic. It’s a concept that I’ve noted before, but
today I’ll try to provide a deeper and more complete explanation.
Economists
have a well-evolved vocabulary for many of the concepts I’ll try to explain
below. But I’m not an economist and
would likely trip over my word choices if I pretended to be one. So I’ll write in my own lay words. And if the economists among the readers want
to recast my arguments into the economist dictionary, please do so.
The root of traffic
congestion, and the resulting problem of induced traffic, is related to how
public agencies set, or don’t set, prices on scarce resources.
In the
private world, the free market system with its rules of supply and demand usually
governs. Given tee times to fill at a top-rated
golf course, the green fees are set high.
If surplus demand still remains, the green fees are bumped even higher
until the demand for tee times eventually matches the number of tee times
available. Given rooms to fill at a nice
hotel, the same rules apply. Diamonds to
sell? Same rules. Adjust the price until supply and demand
meet.
The supply
and demand system is marvelously elegant and intuitive. And for the most part, it works well. Some may not like the answers that pop out,
but the market usually tends toward logical and rational.
But we, as
represented by our various levels of government, typically have an aversion to
the applying the same market rules to public resources. We don’t want the best camping places going
to millionaires driving tricked out recreational vehicles. And we don’t want to dole out hunting permits
only to the well-heeled.
So instead,
we devise a range of non-price systems to allocate scarce resources. Have a campground that’s usually full all
summer? Institute a policy that requires
advance reservations on a first-come, first-served basis. Managing a trail that has excess demand? Devise a lottery for hiking permits. Afraid that unfettered fishing will exhaust a
stream? Implement rules like
catch-and-release, closed seasons, and catch limits to reduce pressure on the
fishery.
But there
are also public resources to which we don’t choose to apply significant impediments. At the top of that list is street capacity. Given that most people already have cars and
drivers licenses, the only barriers to driving extra miles, whether on open
country roads or congested downtown streets, is the incremental vehicle
wear-and-tear and the cost of gasoline, neither of which is a significant
barrier.
To understand
the implications of this absence of obstacles to driving, let’s try a thought
experiment.
Presumably
all are familiar with the scenic wonders of Yosemite National Park. Access to Yosemite is well-regulated by
entrance fees, high cost hotel rooms, advance registration campgrounds, and
hiking trail lotteries.
But imagine
if Yosemite management decided that the barriers to park use were too
high. To allow more folks to partake of the
park, they clear a meadow on the valley floor, throw a fence around it, and
open it to unlimited camping use. No
reservations, no fees, no designated camp sites. Just an open gate. People could pitch tents wherever they wished,
with no standards about how far they needed to be from other tents. (To be clear, I’m not suggesting this
idea. I’m only offering it for thought
purposes.)
What would
happen? Obviously, the campground would
fill quickly and campers would soon be stepping on each other’s toes. Some campers would give up and go home, deciding
that a vista of Half Dome wasn’t worth being unable to warm one’s hands at one’s
campfire without burning one’s backside on a neighbor’s campfire. But plenty of campers with a high tolerance
for crowding would remain.
Now let’s
say that Yosemite management, looking at the “success” of the new campground,
decided that the concept was valid, but that the overcrowding had become too
burdensome. To allow more spacing
between tents, they decide to open a second campground with the same set of
rules, arguing that the density of campsites will thereby be halved.
But that’s
not what would happen. Remember the
campers who went away, turned off by the lack of space between tents? They’d come back, happy to camp with even a
little more space. The congestion in the
second campground would quickly rise to nearly the same level as the first
campground.
Obviously,
there would some number of campgrounds that would satisfy the demand for cheap,
no-frills Yosemite experiences, but the entire valley floor might be consumed
before that point is reached.
And that’s
exactly what happens with congested city arterials. Some may argue that traffic congestion would
disappear with new road capacity, but the reality is that campers, I mean
drivers, who had previously deferred trips would return to congest the new
roadway.
Nor is this
a hypothetical supposition. Study after
study shows that a large chunk of new roadway capacity is consumed on the day
it opens, with the remainder consumed in next few years, even in the absence of
new development.
This finding
is why the State of California is implementing new rules to judge environmental
impacts based on traffic generation, not
congestion. Unwilling to await the new
state rules, the City of Pasadena implemented their own rules to the same
end.
(Side note:
When the Petaluma Planning Commission reviewed the Draft Environment Impact Report
for the Rainier Connector, some Commissioners noted the surprisingly small
congestion relief benefits projected as a result of the new road. But under the pending revised California
rules, which measure traffic generation in place of congestion relief, the balance
would make the outlook even worse.
Instead of a minor benefit, the traffic impacts of Rainier Connector
would be judged a negative.)
So when the
correspondent asked about “achievable alternatives”, his underlying supposition
was flawed. Not only are there no achievable
alternatives, but even the preferred solution of the Rainier Connector wouldn’t
provide the promised benefits. Induced
traffic undermines any attempt to reduce traffic congestion by building new
roads.
Urbanism can’t
solve the problem of induced capacity, but it can offer a different land-use
paradigm and set of tools that would make traffic congestion less of a daily problem.
The paradigm and those tools will be covered
in my next post.
Schedule Reminder
The meeting
of Petaluma Urban Chat to take a renewed look at the Sonoma Marin
Fairgrounds is rapidly approaching. It’ll
be Tuesday, November 11. To accommodate the
anticipated larger than normal attendance, the meeting has been moved to Taps
at 54 E. Washington Street in the River Plaza shopping center. We’ll convene at 5:30 and likely conclude
shortly after 7:00. Please be on time
because the evening is expected to be full.
Some have
asked about a recap of earlier meetings.
The topic of the fairgrounds was originally broached back in July. As the early meetings progressed, two updates
were provided here and here, and then a couple of points required clarification. The coming meeting won’t necessarily build on
the earlier meetings, but familiarity with the previous conversations may be
useful.
I look
forward to a successful meeting and to chatting with many of you.
As always,
your questions or comments will be appreciated.
Please comment below or email me.
And thanks for reading. - Dave Alden (davealden53@comcast.net)
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