To consolidate, disseminate, and gather information concerning the 710 expansion into our San Rafael neighborhood and into our surrounding neighborhoods. If you have an item that you would like posted on this blog, please e-mail the item to Peggy Drouet at pdrouet@earthlink.net
Computers
have brought us many great things. Online shopping. Streaming movies.
Minecraft. And, lest we forget, variable speed limits.
If
you're not familiar with variable speed limits, they're exactly what
you'd think: traffic systems designed to change speed limits in a given
area, based on weather, traffic, and other factors. Variable speed
limits have been used in parts of the U.S. for over 50 years, with
Michigan rolling out one of the country's first programs in 1962 (PDF).
However,
variable speed limit systems don't always rely on advanced technology.
For example, some are designed to change speeds during particular times
of year. That's how it works on an interstate in Wyoming,
where top speeds are reduced during snowy, icy winter months. The
Cowboy State's system wasn't meant to be responsive to minute-by-minute
conditions; limits change based simply on the day of the year.
But
of course, other systems now deploy an array of sensors to assess
weather, traffic, and other factors when changing speed limits. That's
the kind of system that's headed to Atlanta, Georgia -- arguably, one of
the most congested cities in the country.
According to the Georgia Department of Transportation website,
I-285 is a trouble spot -- specifically a 36-mile stretch of it,
located to the north of the I-20 interchanges. This section, called the
"Top End", is where variable speed limits will be introduced this
September. The DOT says that it hopes the system will make I-285 safer
and less congested.
The
DOT says that it'll accomplish that task by keeping traffic moving at
the same speed. While speeding itself can cause accidents, a major cause
of collisions is "speed variance",
or travelers moving at vastly different velocities. The new system in
Atlanta aims to mitigate the possibility for differences by ratcheting
down (or up) the speed limit from a maximum of 65 mph down to 35 mph,
using a network of 176 digital signs. Though traveling down an
interstate at 35 mph is no one's idea of fun, the DOT says that it's
safer and more efficient for drivers to slow and move at the same pace
than to keep a higher speed limit, which encourages stop-and-go
traffic.
And for those who think that police are always looking for ways to write more traffic tickets (not a stretch, since many cities depend on revenue from
citations), Georgia's DOT states very clearly, "Our ability to remotely
change the speed limit on the corridor is not intended to create speed
traps. Rather, the changing speed limits are designed to create safer
travel by preventing accidents and stop-and-go conditions."
Georgia
officials say that the new system is inexpensive and easy to roll out,
with a strong return on investment. They hope to see results similar to
those of a variable speed limit system deployed in Washington state,
which curbed collisions by 13 percent and injuries from collisions by 10
percent.
For additional details about Atlanta's new variable speed limit system, check out the DOT video, embedded above.
