I can think of two phases. First, the problem is with people who don't have an address. They currently have to say "send an ambulance to the blue building just

I can think of two phases. First, the problem is with people who don't have an address. They currently have to say "send an ambulance to the blue building just above the X gas station near the police station in west Y". Having some sort of address - even with ambiguity! - is better than now. And we don't know if there is local ambiguity. (Also, dialects make a difference. My dialect has "pen/pin" as a homonym. Rhoticity adds another layer of complications.) Then again, we already have homonym problems. For example, "Greene St." vs "Green St." Newark, Jersey City, NYC, and Brooklyn each have one or the other, within a span of a few miles. For the ambulance problem, E911 system in the US has a rough idea of where you are calling from, and can help disambiguate. Which means we know it's possible to build a system on top of similar names. But the first step is to get some names.