Double nickels are not
a good idea
Matthew E. Caster
Some of you are already dealing with the
most cataclysmic change in Houston in decades, while others stand aside
and wait before it hits
them too. Virtually unanimous outrage
at this decision has already poured through the media.
Mothers cringe at the thought that their
children might someday have to live under the tyrannical rule of the infamous
"double nickels" — not
so anyone would actually notice, but the
speed limit on all Houston freeways is in the process of dropping from
whatever it was (no one really
knew) to 55 miles per hour.
The magical number 55 was chosen specifically
because tests have shown it is the speed at which vehicles travel the farthest
using the
least gasoline. The "highway" mileage
shown on new cars is the number of miles a vehicle would travel at exactly
55 mph using precisely
one gallon of gasoline.
This catastrophe is actually a calculated
measure by federal and state agencies to reduce pollution levels in Houston.
Their statistics show
our city to be the second-most polluted
in the United States.
The whole proposal is absolutely absurd.
Not only are the attempts to fix the problem not likely to have a significant
impact, but the problem
itself is difficult to properly define
and measure.
For starters, it is important to question
what the big deal is. All of this madness began when Houston, for a year
or so, usurped the most
polluted city title from perennial and
current champion Los Angeles. Granted, Houston pollution is bad ... but
surely it could not be worse than
Los Angeles'. But sure enough, Houston
had more days of hazardous pollution than that dump in 2000.
After a bit of research, I found out why.
Know where pollution ratings for Houston are taken? Deer Park. Deer Park?
They might as well place
the measurement equipment inside a smokestack.
So Deer Park is one of the most polluted
cities in the country. So how would lowering the speed limit where I live
(approximately 55 miles
from Deer Park) lower the pollution level
measured just downwind of the Chevron refinery? It wouldn't.
But for the sake of argument, let's focus
on the Katy Freeway, the most congested freeway on Earth. Information from
the Texas Department
of Transportation shows that Interstate
10 west of Houston averages almost seven hours of "rush hour" and 17 hours
of "congestion" every
weekday. "Rush hour" traffic occurs when
traffic moves less than 30 m.p.h. on average. "Congested" traffic occurs
any time traffic moves an
average of at least 10 m.p.h. slower than
the posted speed limit.
Fuel economy reaches a maximum at 55 mph,
and deviating from 55 lessens fuel economy whether you're moving faster
or slower. Fuel
economy at 70 mph is typically similar
to fuel economy at 45 mph. When a car is moving at less than 30 miles per
hour, it burns about half as
much fuel as it would at 70 mph ... but
it's moving less than half as fast; you burn more gasoline for every mile
you travel.
Pollution is a problem in Houston, no matter
where it's measured. The matter seems to have been overblown a bit, of
course, but it's still
something we should try to reduce. Other
measures, such as tighter industrial pollution controls, are a good idea
and will help ease our
pollution crisis. But if our goal is to
reduce automotive pollution, there is one thing we must do before we lower
the speed limits, and that's
widen the highways enough so that traffic
can actually travel at an efficient speed.
