Jussi,
In a nice, polite way during your discussions with your local utility provider you can mention you operate a federally license radio station that is experiencing power line interference. They are required by law to resolve this issue although sometimes the responsiveness from utilities is less than desirable. It took me about a year to get things rolling here but I now have a good rapport with the responsible engineer.
The important thing is they understand you are not just a CB’er or someone randomly operating some radio station that is not licensed, but rather you are operating a federally licensed radio station under 47 CFR Part 97. Again I emphasize dong so in a “nice” manner!
Well, here we don't have ANY numbers on these poles. As I said earlier they don't have tracking system for reported problems, they don't know about RFI. I wonder what I find next. These should be rather basic things for any power company to have. At least they seem friendly and somewhat responsive. So, I guess it could be worse.
Jussi (aa6kj)