Post-Striping Results from the Village

Hello Greenleaf!

I just received the raw speed results from the Village.
I have also done some preliminary analysis here.
The raw results are in PDF form - which unfortunately Google does not support for publishing to Blogger - but I can email them to you if you email me at restoregreenleaf@gmail.com.

My initial conclusion is that the data shows the striping has clearly not worked, and that we need to pursue other alternatives.

1. The results do NOT demonstrate that the striping has reduced speeding on Greenleaf:

a. The Village has provided no pre-striping comparison data for the eastern half of the street (400-700 block).. and the results show there is still a substantial amount of speeding going on.. with over 50% of cars speeding on the Eastbound 400 and 500 blocks.. and approximately 35-50% of cars speeding on the 400 through 700 blocks in aggregate.

b. The post-striping data for the western half of the street (800-1000 block) appears to have two significant bias issues. All the readings except for the eastbound 900 block were taken on 4/20 through 4/24 when there was a highly visible portable radar unit on the 700 block of the street. This would have biased speeds downward. Furthermore, the post-striping data for the westbound 800 block was taken from a Nu-metrics unit that appears to be calibrated incorrectly and biased downwards. The two samples from this Nu-metrics unit (#3291) show results that appear anomalous and downwardly biased when compared to the samples from the neighboring blocks. Even with these biases, the Westbound results for the eastbound 800 and 1000 block showed no significant change, and the 900 block showed only a 1mph decrease in both directions. The westbound 800 block which is biased by both the portable radar unit and the poorly calibrated Nu-metrics unit shows a 6mph decrease.

2. The results indicate a much lower ADT (average daily traffic volume) on the eastern half of the street. Further calling into question why Greenleaf should have a centerline. According to Department of Transportation code, centerlines are normally reserved for streets that have 2-3x the volume of Greenleaf. There is no safety reason for having the centerline, several US municipalities narrow streets with edgelines AND without centerlines (Pasadena, CA, Alameda, CA, Anne Arundel County, MD, etc, etc.)... And we have already pointed out studies that show centerline REMOVAL significantly enhances safety on roads like Greenleaf.

3. The data illustrates we need to pursue other alternatives (lower speed limit? stop sign? remove the centerline and/or parking lanes?) to calm traffic on Greenleaf.

I'll look forward to our further discussion with the Village.