This segment is incorrectly marked with a left turn from RT-15 North to the I-390 interchange access road. This particular left turn is prohibited.
Thanks!
Why is it prohibited? I find it hard to believe that access to the interstate is not allowed. Is there a major construction project going on?
The answer to that is above my paygrade. You’ll have to ask the state traffic engineer in charge of this area, but see for yourself.
Then the answer is likely above your paygrade as well. Keep that in mind next time you glibly dismiss an update request while denigrating the requester. It tends to turn people off to participation.
No.
I’m not dismissing the update request, nor am I denigrating you. If you think I am, I’m sorry you feel that way, trust me, I’m not. I’m just trying to figure out why you can’t turn left there before I go ahead and either unlock it or turn the left turn off.
It has now been fixed. And a simple “because there is a no left turn sign at that intersection” would have been a sufficient reason for wanting the left turn prohibited.
Actually, the reason is quite simple, requiring neither a high pay-grade nor a rocket science degree 
to understand: there’s no need for anyone to turn left there!
Look at the interchange as a whole – if you want to get onto I-390 S from SR-15 N, you should take a left on SR-251 W, which takes you directly to the onramp. (And if you’re just trying to do a U-turn from I-390 N to get back onto I-390 S, taking a left from the offramp onto SR-251 W is still the correct way to go.)