UPDATE: These declines are even larger than first reported. They are not the total decline from the first date to the second, but an average decline PER YEAR from the first date to the second.  The total declines are more like 20% for most of these intersections.  That’s a huge drop!

While metro Atlanta’s population exploded since 2000, smart (growth) ol’ Decatur actually experienced a decline in cars on the road during the same period according to GDOT and other independent data. Where can one find this particular data? Out of the 315 W. Ponce traffic study!

While I did take note of this data on page 6 of the study the first time I went through it, Lyn prompted me to go back and take another look.

There’s two sets of data…first from the GDOT…

At the intersection of Church and Ponce, traffic declined 4.31% PER YEAR from 2001 to 2006.

At the intersection of Clairemont and Garden Lane, traffic declined 4.37% PER YEAR from 2001 to 2006.

The other set of data uses a much smaller base (hundreds instead of thousands) and compares count data from a 1999 “speed study” to data collected specifically for the 315 project.

At the intersection of Ponce and Ponce Place, traffic declined 2.65% PER YEAR from 1999 to 2008.

At the intersection of Fairview and Montgomery, traffic declined 4.31% PER YEAR from 1999 to 2008.

At the intersection of Oakland and Wilton, traffic declined 3.63% PER YEAR from 1999 to 2008.

At the intersection of Oakland and Ponce Place, traffic declined 2.35% PER YEAR from 1999 to 2008.

Lyn also hinted that a GA Tech carbon emissions study, which will be presented at the commission meeting tonight, will also back up the data above.