> we tried relentlessly to contact our local utilities to gain access to their underground conduit and was never able to get someone on the phone or even much of a response.

I find that really hard to believe. Go to their offices and ask for the manager.

> I eventually got to the point where I was like, "Fk it, I'll do it on my own." Now we're looking at microtrenching, which is probably an even larger endeavor, but at least we'll own the conduit.

Building your own facilities is no joke. Unless you are made out of money, you'll be far better off putting more effort into renting existing ducts.