zipcode boundaries from Tiger
tom at flood.com
Fri Jun 10 14:19:54 EDT 1994
mgfleury at netcom.com (Mark Fleury) writes:
| My understanding from talking with Census is that ZIP code info not a part
| of TIGER. Some features (<1%) may have ZIP info. My efforts to build ZIP
| polygons produced a few disconnected line segments. Census would like to
| include this info in TIGER2000 but are under severe budget limitations.
| Also: In detail ZIP boundaries are continually changing to meet mail
| delivery needs.
| If ZIPs are located between street blocks (along allyways) as are many
| voter districts, the location would have to be moved to an existing TIGER
| feature (not correct) or new featrues would have to be added to TIGER.
| This could nearly double the size of highly urban county files - would it
| be possible to handle Los Angeles County at over 300Mbytes? And TIGER
| itself would increase at $250/CD-rom.
| I too wish the ZIP data was in TIGER, but doing so might create a nightmare.
GDT's DynaMap data products have most all of the zip code information
you'd want, since their database is maintained by cross-referencing
Tiger data with USPS data. They have also taken care to make sure
that the boundaries of various objects such as ZIP codes, cities,
tracts, etc. line up the way you'd expect. DynaMap costs more than
TIGER, but then you get what you pay for...
Tom Chatt \ Don't take offense, take action.
Internet: tom at flood.com \ Speak up. When we remain silent,
UUCP: ...!uunet!flood!tom / \ we oppress ourselves.
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