I know that intersection well. Call 311 or email them, they have been really good when I've emailed them about street sign problems. I am on a one-way and when a tree began obscuring the sign, we got lots of wrong-way cars. The city came out within 24 hours of my email and trimmed the branch. Probably the issue you mention is more involved but definitely call/email them. One cool thing about using the email is that you can track all the channels through which your query travels.