Totally low; nothing but a scrape.
Width: 75' - 120' Length: 620' (from under bridge to bottom ledge)
Immediately under the Monroe Street (CTH.PP) bridge lie a few small ledges (best one(s) lie(s) to the right of the bridge pier). Just downstream lies the bigger ledge/combination.
Starting left of the bridge pier, if you stay fairly centered in this side of things, the gradient is mostly a steep sliding drop. The more to the right you run (of this river-left side of the bridge-pier), the more 'stepped' the drop becomes.
If you go to the right of the bridge-pier, after passing the small ledge and/or wave under the bridge (COTF surf?) you may be able to charge hard to the left to 'boof' off a part of the ledge below which lies parallel to the shores, then down the lower half of the left-center slide. Otherwise (staying straight ahead from river-right of the bridge-pier) all the gradient is dropped in a two-step ledge. The first 'step' varies a bit in width, so the location you drop it (and, of course, the flow) could significantly affect your ability to control how smooth or rough your 'double-boof' will be. Water will generally sheet pretty fast and shallow across both the mid-step and the base of this ledge, so expect a 'hard' landing! (If you land bow 'down', it will be particularly unpleasant!)