Elaine,
Please excuse my ignorance. I have had questions about how the Census Dept. would collect
TAZ data for the Census. I have been waiting for information like you have provided
below. Can you give me any additional information? We are in the process of modifying
our TAZ structure now and want, If possible to use the new information in this count. Any
thoughts?
Thanks,
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From: ctpp-news-bounces(a)chrispy.net [mailto:ctpp-news-bounces@chrispy.net] On Behalf Of
Elaine.Murakami(a)dot.gov
Sent: Wednesday, October 06, 2010 10:32 AM
To: ctpp-news(a)chrispy.net
Subject: [CTPP] TAZ delineation for CTPP (2006-2010) tabulation SCHEDULE
At our monthly CTPP Technical meeting last week, April Avnayim of the Census Bureau
Geography Division, gave us an update on the TAZ delineation software schedule.
November 2010: agencies verify contact names by reviewing file at Cambridge Systematics
ftp site, and report any changes to Liang Long.
December 2010: final delivery of software by Caliper to CB
February 2011: web-based training coordinated with FHWA
January thru March 2011: delivery of software and Census 2010 data and geographic files
on a rolling basis.
Each state will get 3 - 4 months to delineate their TAZ and TADs and return the files to
the Census Bureau.
July 2011: all files MUST be returned to CB Geography Division.
Please note: TAZs for CTPP tabulation do not necessarily match the TAZs for your travel
demand model. Because the ACS sample is small, some agencies are planning to make the
TAZs for CTPP LARGER than their model TAZs, e.g. combining their model TAZs together.
Also, TAZs for CTPP are census block equivalencies. You will NOT be able to modify the
TIGER segments (which was possible in the CTPP2000). Finally, agencies are NOT required
to define TAZs or TADs. If you do not define TAZs, then census tracts will be used as the
default geography for CTPP (2006-2010) tabulation. However, even if you do not define
TAZs, we recommend that you create TADs (population threshold of 20,000) by combining
census tracts together.
The TAZ business rules are posted on the FHWA webpage:
http://www.fhwa.dot.gov/ctpp/tazddbrules.htm<http://console.mxlogic.com/…