Kansas Association of Mappers

Hey there KAM partners! I got a concern regarding Zip codes... A few years back we had a battle over zip codes with two post offices, upon dealing with that issue I realized we had TWO different zip code boundary layers in our databases. So at that time working with both post offices, we agreed on ONE layer, and I sent maps and letters to all post offices explaining that this is what we would be using from that point forward and in order to change we needed written agreement with postmasters if we needed to change anything. So now we are back to this coming up again, I got a resident that swears his address is in one and not the other, after talking with one of the postmasters she says yes, she delivers and has always not only that but saying we had a whole area that should be hers (Altoona) and not Fredonia's. I sent out a test mail to Fredonia's and it came back as undeliverable "no such number", So the resident is probably correct, and it should be Altoona so I changed his mailing but not the situs since for 911 purposes it would cause the address to be in error.  I went to DASC and looked at what they had, it shows an updated version of 2022, that layer is different than the one I have NOW, So I am just frustrated a little with these zip codes changing and so many versions all over the place. So, can you all shed some light on how you're dealing with Zip Codes, as far as do you update them, and if so then that means updating 911 data as well correct?  roads, address points... I have borderline residents that insist on using a certain ZIP even thought my 911 data suggest otherwise so for these I just change the mailing and leave the situs. But I would like some set in stone ways on dealing with this. Also does anyone know IF a zip code boundary changes how is that done officially with the USPS headquarters, because my local postmasters don't really seem to know either. Thank so much for anyone that can offer anything. 

Seward has similar issues.  What I was told when we had issues after readdressing the entire county is that a residence can physically be within one zip code boundary but delivery is from a different zip code.  The confusion there is real.   USPS puts an address delivery on the route where it is the easiest and most economical for the carriers.   We have some addresses that USPS refuses delivery to because it is in between boundary lines of carrier routes.  USPS forces those people to get PO Boxes.

We have a field in our address points "POSTDEL".  If the zip code for the P.O. that delivers the mail is different than the zip code of the mailing address, we keep enter that mail delivery zip code in that field.    As the rural area continues to get developed with new houses, the PO switches delivery around based on # of customers on each route.  So they leave the zip code the same but a different postal delivery carrier might deliver the mail.