By walking back down the ramp from it to the regular sidewalk. I just meant I want to add elevated walkways to cross streets with, not for them to replace sidewalks entirely.
Otherwise, what you're describing sounds like someone looked at this well-circulated cartoon and said "hey that's a great idea! Just raise the planks by 15 feet!" https://www.vox.com/xpress/2014/11/18/7236471/cars-pedestria...