I am a blind traveler who is petrified of crossing streets.  Those signals help if they're silent--stopping traffic only.  If there are buzzers or beeps, it's very disorienting.  I would just as soon have the ability to turn right on red revoked.  That's more of a hazard than a busy intersection ever thought of being.  Please let me stress this point!  Any help should be silent--only holding the light time to permit crossing.  Those signals come from above and are a bit like walking down a strip of lawn mowers.  They echo off everything and serve to do nothing but scare me worse.  As for detectable warnings, most curbs are fine, and it would only affect where there are sidewalks.  If you live someplace where there aren't any, it would be totally prohibitive to provide them.  If there are sidewalks, I would think you could ask the NFB or some other blind organization to do a poll or something to determine what are bad curbs for blind people who travel a lot and only refurbish those.  Thank you for actually taking the time to consider my opinions.  We can't see, but most of us have fairly good reasoning and decision making capabilities.  We should use them--traveling or otherwise.  Sound cues are helpful--if they're the right ones. 

Sincerely,

Vicki F. Black