The USDA Streamline refinance program started in 2012 as a pilot in several states. However, it quickly proved to be a success and created outcomes correlating with homeownership stability. As such, the program has expanded nationwide.
The only location requirement is that you be in an area that would normally be USDA-eligible, typically on the outskirts of suburbia or in a rural area far away from major population centers. You can check if your property is in an eligible area on the USDA website.