Site 70 has a 50 amp hook-up,but does it also have a 30 amp hook-up as well?

Yes, there is both 50 and 30 amp, but no sewer hookup.

When I've stayed there, I've only used the 50 amp. You May want to bring an adapter, just in case. Oh, and it might rain there so bring a blue tarp.

It has 50, 30 and 20 plug-ins.

The site I stayed at had 20 amp, 30 amp and 50 amp servive available . You could just plug into the amperage of your choice and then flip the breaker on. :)

Their site says 50 amp

We have stayed in that site. I'm going with it does. Have fun!