I published a blog in March 2010 entitled "The Zip Code Follies" describing how Mequon residents living in the 53092 zip code constantly receive commercial mail and mail order packages addressed to Thiensville. This is the result of the sender using the USPS software which returns Thiensville when they enter the 53092 zip code. If one has Time Warner broadband service and inform it that you live in 53092 you get Thiensville weather and gasline stations on Port Washinton Road as being located in Thiensville. When the US Census Bureau sent out their surveys to Mequon residents in 53092, they were addressed to Thiensville. When I got mine, I thought we all might be counted as residents of Thiensville so I approached the US Postal Service to ascertain whether Thiensville could be assigned 53092 exclusively and Mequon 53097 which now just covers parts of Mequon's western and northern areas. The number of residents included in these two zip codes is as follows: in zip code 53092 -Thiensville 3,374 and Mequon - 18,894; in zip code 53097 - Mequon - 4766. My approach to create separate zip codes for Thiensville and Mequon was summarily rejected by the USPS as not feasible under their operating rules.
With that defeat under my belt I went back to the drawing board. Further research uncovered that the USPS web site for zip code 53092 lists Thiensville as the primary location and Mequon as an alternate. This explains why commercial software systems call up Thiensville whenever 53092 is entered regardless of your Mequon location. I recontacted the USPS explaining that the current 53092 service area covered 5.6 more Mequon residents than Thiensville residents, (18,894 to 3374) With that information confirmed, the USPS responded positively to interchanging Mequon and Thiensville - that is Mequon would be primary and Thiensville as alternate on their 53092 software. With this change, commercial software programs will display Mequon for 53092. The USPS indicated that they would contact both Mequon and Thiensville officials and receive their comments.