Call for Beta Testers/Feedback on Census Bureau Options: 2020 Block Group/Tract Delineation Update

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bgruswitz
Call for Beta Testers/Feedback on Census Bureau Options: 2020 Block Group/Tract Delineation Update

All,

 

Thank you to all who submitted comments seeking to
update the rules for block group and census tract delineation for the 2020
Census Participant Statistical Areas Program (PSAP). The transportation
planning community’s submissions were substantial and the Census Bureau is
interested in finding a solution to our needs while working within their own
limits to ensure standards for survey data quality and privacy concerns.

 

The Census Bureau has distilled comments relating to
combining residence-based and workplace-based delineations into three options
and has asked us to give feedback on how workable these options may be. Two of
them seem more plausible for the Census Bureau’s final ruling on 2020 PSAP
criteria, but may be more limiting than transportation planners would desire.
We are seeking people willing to test out these options with their own
geographies. We’d like to know whether one option is more workable or
preferable than the others--and why. Do some options work better for single-use
geographies but not as well for mixed-use? Do they work better or worse than
how your TAZs are currently delineated?

 

We will use this survey form (https://goo.gl/forms/SgHrqne2NhGjUsEr2)
to collect comments about folks’ observations when testing the options. Time is
limited, as the Census Bureau has only this summer to finalize how PSAP 2020
will work. If you’re willing to test one
or more of these options in a sampling of your communities and workplaces, we must
receive your feedback by June 20.
If you’d like to view others’ comments
before or after submitting your own, scroll to the bottom (leaving the form
blank) and press submit. You will have the opportunity to see your own answers
after submitting and to revise your response, if desired.

 

One of the key differences--highlighted in the options
below--between the needs of the ACS and the CTPP special tabulation is that the
ACS does not report workplace geography below county subdivision or census
designated place. CTPP will continue to seek workplace and journey-to-work
flows by tract--and in post 2020 releases--block group. It may be desirable for
CTPP data quality to see workplace-based geographies with employment counts
high enough to get a reasonable samples of workers at smaller geographies, but
the Census Bureau has no need for ACS reporting to see block groups meet a
minimum threshold of employment--especially when it comes from a local source
they have no way of verifying. In other words, the CTPP Oversight Board’s
recommended comments of a minimum threshold for employment for block groups and
tracts (on par with population minimum thresholds for those geographies) may be
good practice for delineating to get better workplace data in the CTPP, but may
not be necessary from the Census Bureau’s perspective.

 

Please try these criteria for delineation on your
current geography and add your comments to the google sheet

 

Option A:
Employment thresholds where population or housing is not present

This scenario gives priority to population or housing
units for delineating standard block groups (min: 600 people or 240 housing
units; max: 3000 people or 1200 housing units) and tracts (min: 1200 people or
480 housing units; max: 8000 people or 3200 housing units). If an area was
devoid of population or housing, that area could be delineated by a minimum
threshold of 600 employees per block group and 1200 per tract. Special Use
block groups and tract criteria would stay the same (Within an urban area: min.
1 square mile; Outside an urban area: min. 10 square miles).

 

Option B:
Only need one threshold met--population, housing or employment

This scenario allows for some presence of population
or housing that may or may not meet a minimum threshold, as long as it meets an
employment minimum of 600 jobs in block groups or 1200 in tracts. Conversely,
it allows for population of 600-3000 in block groups or 1200-8000 in tracts
without meeting a 600 or 1200 job threshold, respectively. Special Use block
groups and tract criteria would stay the same. This is seen as a very unlikely
option from the Census point of view because it would degrade resident sample
sizes to a point where disclosure would be a real concern.

 

Option C: Special
use block groups and tracts have no minimum area criteria - no employment
thresholds

Rather than seeking employment thresholds, removing
the square mileage criteria of the special use block groups and special use
tracts would allow agencies to define non-residential land in whatever way they
want. If there is no presence of population or housing units, non-residential
land-uses could be carved up by block group and tract boundary rules (see below
info on boundary rules below). Those concerned with achieving a minimum sample
size of workers at workplace may opt to consider employment counts while
delineating, but would not need to report this as justification for where
proposed tract and block group boundaries are delineated. Residential areas
would follow current standard block and standard tract population/housing unit
thresholds.

 

What PSAP
guidance says on boundary line features:

For tracts, beyond using governmental (County,
reservation or MCD [where applicable]), or “permanent natural and constructed
features, such as roads, shorelines, rivers, perennial streams and canals,
railroad tracks, or above-ground high-tension power lines”, the federal
register allows: “boundaries of large parks, forests, airports,
penitentiaries/prisons, and/or military installations, provided the boundaries
are clearly marked or easily recognized in the field in imagery and on the
ground.” Barring all that, it says: “When acceptable visible and governmental
boundary features are not available for use as census tract boundaries, the
Census Bureau may, at its discretion, approve other nonstandard visible
features, such as major ridgelines, above-ground pipelines, intermittent
streams, or fence lines. The Census Bureau may also accept, on a case-by-case
basis, relatively short stretches of boundaries of selected nonstandard and
potentially nonvisible features, such as cadastral and parcel boundaries or the
straight-line extensions or other lines-of-sight between acceptable visible
features.” More details here: https://www.federalregister.gov/documents/2018/02/15/2018-02625/census-t...

 

For block groups, the same can be said, with the
addition that any block group “nest” within its “parent” census tract. More
details here: https://www.federalregister.gov/documents/2018/02/15/2018-02624/block-gr...

bgruswitz

Just a reminder to get your comments in by tomorrow if you would like to provide your feedback on the PSAP options described below. Thanks to all who've submitted comments so far! Again, you can see what others have submitted by submitting a blank form on your end. I believe we have 5-6 comments by this point.

Ben