This was posted on an engineering forum that I visit often. Don't know the accuracy of it but it sounds interesting. BTW wheck out that last line!
"Highway lighting power is either 480 volts 2-wire end grounded or 240/480 volts 3-wire single phase. Some parts of Cleveland Public Power have 480 volt ungrounded single phase streetlighting power. Cleveland Public Power did not start grounding their stuff until 1991. You do not want to step on a CPP handhole cover or lean against a streetlighting pole in Cleveland, Ohio because CPP's stuff is only Code 2 out of 3 times. In the late 1980s they were still using GREEN hot leads"