A question about USPS mail delivery

May 3, 2024 6:24 PM

Something I've always wondered about USPS mail delivery routes: why are 2 very close areas delivered hours apart?

We used to live somewhere that got the mail roughly around 10 am each day. We moved about a mile away several years ago. Now, our mail gets to us around 3 or 4 pm. Same small town (<3k people), same zip code.

Not complaining, just wondering: how are the routes determined that this is the most efficient way to deliver?

posted by cozenedindigo to Grab Bag (3 answers total)

Lots of variables here.

There might two different postal workers with two different routes.

Route itself could have been readjusted.

While sometimes a "sequence order" is handed down, it's really most up to the carrier to decide on what gets delivered in what order. There is a lot of 3rd party software used for this purpose. Perhaps you carrier has now decided you are at the end of the route now verses the beginning.

While there are "working hours" of course, delivering mail is really a "you quit for the day when the job is done" type situation. So, your carrier might have had life situations that made it more convenient to bang it out super early, but now there is more a late start.

Anyway, could be lots of reasons.

Related to the above, perhaps you experienced carrier left the job, and now a series of inexperienced replacements have taken over and they only get as much work done by 3pm as your old person did by 10am.
posted by Back At It Again At Krispy Kreme at 7:37 PM on May 3 [5 favorites]

I look at old census books for genealogy quite a bit. Sometimes I'm trying to find out everyone who lived across from each other on the same block, or on the same street but a block or two down. Sometimes it works out nicely and it's a matter of turning a page or two, but sometimes census takers took routes that meant the people on the other side of the street were done days (and many pages) later. People can only go in one direction at a time. You just happen to be closer to the end of someone's route now than you used to be. A new carrier could choose to deliver your route differently than the current one does.

We had a sub for our carrier for a couple weeks and suddenly got mail in the morning, then our regular carrier returned and we went back to getting afternoon mail. And for a awhile there must have been many people out or something because there were a couple months we were getting basic mail as late as 10pm.
posted by oneirodynia at 9:49 PM on May 3 [2 favorites]

> People can only go in one direction at a time.

This is a good insight.

Imagine there's a small town with four quadrants, arranged like this:

A B
C D

What order are you going to deliver to them in? Well, it doesn't really matter -- start anywhere, go clockwise or counterclockwise -- so let's say C–A–B–D. Now the people in neighborhoods C and D are wondering why they're hours apart. They're right next to each other! But if C and D weren't the first and last, some other pair of adjacent neighborhoods would be. That's just the nature of trying to snake through a two-dimensional space in a linear fashion: some neighbors in space won't be neighbors in the route.

You can see this effect when walking a labyrinth: you can have a long head start on another walker, but they'll still pass right by you several times: points that are far in time are near in space. (And you might think this is because labyrinths are purposely inefficient, but they aren't! No matter how you fill up a given area A with a path of width w, the path will be about the same length, A/w. So there's no particular reason for postal routes not to be labyrinth-like.)
posted by aws17576 at 10:54 PM on May 3 [2 favorites]