Currently, it is not possible to reproject a built utility network. The only way to do this is to go back to the asset package "level", reproject, and build the UN back up. I understand the initial logic on the design decisions on why the coordinate system is "locked down". However, there is a "tsunami" approaching that many in the industry are going to have to deal with that now must be considered.
There have been rumblings about the NSRS 2022 (National Spatial Reference System of 2022) for several years. ESRI is aware of it and has blogged about it. It was obvious in this year's presentation by the National Geodetic Survey at the 2026 UC, that it is coming - most likely sometime in 2027. The NGS has transitioned from the "science phase" to full on outreach mode. They are trying to get the word out that the new system is coming. With this news, there are many many utility networks that will and must be migrated to the new coordinate system. This is essentially any utility in the United States or territories. There needs to be a better way for a UN to move to a new coordinate system than the answer essentially be "start over". Orgs have spent countless hours and money building these networks and only to have to start over to change coordinate systems will be a pill hard to swallow. So, the idea is simple - allow reprojection of a built UN.
